1
|
Alhamoudi FH. Comparing the accuracy of crown fitting between milling and 3D printing techniques using CAD/CAM technologies. Technol Health Care 2024:THC231961. [PMID: 38820032 DOI: 10.3233/thc-231961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2024]
Abstract
BACKGROUND The accuracy of dental crowns is crucial for their longevity and effectiveness. OBJECTIVE This study aims to investigate how the precision of crowns is affected by two different fabrication methods, either subtractive (milling) or additive (3D printing), within computer-aided design/computer-aided manufacture (CAD/CAM) technology. METHODS A standardised digital scan of a maxillary first molar with a shoulder margin (.stl file) was used to design and fabricate crowns through both subtractive (milling) and additive (3D printing) processes. The crowns' marginal and internal fits were assessed comprehensively. Statistical analysis, including two-way ANOVA and independent t-tests, revealed significant differences in fitting accuracy between the two methods. RESULTS Crowns produced via 3D printing demonstrated superior fitting with minimal marginal (14 ± 5 μm) and internal discrepancies (22 ± 5 μm) compared to milling (marginal: 22 ± 4 μm, internal: 23 ± 3 μm), indicating a statistically significant advantage in precision (ps⩽ 0.022 for marginal fit). CONCLUSION The findings suggest that 3D printing may offer a more accurate alternative to milling in the fabrication of digital dental prostheses, potentially revolutionising the field with its enhanced precision capabilities.
Collapse
|
2
|
Suksuphan P, Krajangta N, Didron PP, Wasanapiarnpong T, Rakmanee T. Marginal adaptation and fracture resistance of milled and 3D-printed CAD/CAM hybrid dental crown materials with various occlusal thicknesses. J Prosthodont Res 2024; 68:326-335. [PMID: 37438119 DOI: 10.2186/jpr.jpr_d_23_00089] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
PURPOSE To evaluate the marginal adaptation and fracture resistance of three computer-aided design/computer-assisted manufacturing hybrid dental materials with different occlusal thicknesses. METHODS Ninety single-molar crowns were digitally fabricated using a milled hybrid nanoceramic (Cerasmart, CE), polymer-infiltrated ceramic network (PICN, Vita Enamic, VE), and 3D-printed materials (Varseosmile, VS) with occlusal thicknesses of 0.8, 1, and 1.5 mm (10 specimens/group). Anatomical 3D-printed resin dies (Rigid 10K) were used as supporting materials. A CEREC MCX milling unit and a DLP-based 3D printer, Freeform Pro 2, were utilized to produce the crown samples. Before cementation, the marginal adaptation, absolute marginal discrepancy (AMD), and marginal gap (MG) were assessed using micro-CT scanning. After cementation with self-adhesive resin cement, fracture resistance was evaluated using a universal testing machine. The number of fractured crowns and the maximum fracture values (N) were recorded. Data were statistically analyzed using both one- and two-way ANOVA, followed by Tukey's honestly significant difference (HSD) test. RESULTS For all occlusal thicknesses, the VS crowns demonstrated the lowest AMD and MG distances, significantly different from those of the other two milling groups (P < 0.05), whereas CE and VE did not differ significantly (P > 0.05). All VS crowns were fractured using the lowest loading forces (1480.3±226.1 to 1747.2±108.7 N). No CE and 1 and 1.5 mm VE crowns fractured under a 2000 N maximum load. CONCLUSIONS All hybrid-material crowns demonstrated favorable marginal adaptation within a clinically acceptable range, with 3D printing yielding superior results to milling. All materials could withstand normal occlusal force even with a 0.8 mm occlusal thickness.
Collapse
Affiliation(s)
- Pisit Suksuphan
- Department of Restorative and Esthetic Dentistry, Faculty of Dentistry, Thammasat University, Pathumtani, Thailand
| | - Nantawan Krajangta
- Department of Restorative and Esthetic Dentistry, Faculty of Dentistry, Thammasat University, Pathumtani, Thailand
| | | | | | - Thanasak Rakmanee
- Department of Restorative and Esthetic Dentistry, Faculty of Dentistry, Thammasat University, Pathumtani, Thailand
| |
Collapse
|
3
|
Daou EE, Salameh P. Does the choice of the measuring technique affect the comparison of fit between zirconia and cobalt-chromium prostheses? J Indian Prosthodont Soc 2024; 24:201-207. [PMID: 38650346 PMCID: PMC11129817 DOI: 10.4103/jips.jips_429_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 04/25/2024] Open
Abstract
AIMS The objectives of the study were to compare the adaptation of presintered zirconia and cobalt- chromium prostheses using microcomputed tomography (μCT), scanning electron microscopy (SEM), and stereomicroscope (SM). MATERIALS AND METHODS Twenty-four fixed dental prostheses (FDPs) were fabricated on metal abutments, duplicated from maxillary first premolar and first molar prepared on a typodont model. Teeth were reduced to obtain chamfer of 1.2 mm and reduction occlusaly of 2 mm occlusal. Scanning of the abutments was done with random assignment to two groups receiving the FDPs made from soft-milled Co-Cr (n = 12) and zirconia (n = 12). Marginal and internal gaps were assessed using three evaluation techniques (X-ray microcomputer tomography, SEM, and stereomicroscopy). STATISTICAL ANALYSIS USED Comparison of the results was made using Levene and analysis of variance tests (α =0.05). RESULTS Irrespective of the material tested, statistical differences were found between the measuring techniques (P = 0.001 overall); the obtained mean gaps were for CT scan (92.60 ± 13.31), for SEM (101.92 ± 23.03), and for SM (113.44 ± 14.68): the multiple comparisons between techniques found a significant difference between CT and SM (P < 0.001), and SEM and SM (P = 0.025). When materials were compared within each measuring technique, Co-Cr showed lower values compared to zirconia in SEM (P < 0.001) and Stereo (P = 0.049); similar results were found in CT. CONCLUSIONS Results values differed with the chosen measuring technique. Co-Cr prostheses had a better fit than zirconia prostheses in SEM and Stereo. µCT showed comparable results to SEM, smaller than SM results.
Collapse
Affiliation(s)
- Elie E. Daou
- Department of Prosthodontics, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon
- Department of Fixed Prosthodontics, Faculty of Dentistry, Saint Joseph University, Beirut, Lebanon
| | - Pascale Salameh
- Department of Public Health, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| |
Collapse
|
4
|
Choi H, Jo JY, Hong MH. Marginal fit of three different nanocomposite inlays fabricated with computer-aided design/computer-aided manufacturing (CAD/CAM) technology: a comparative study. JOURNAL OF YEUNGNAM MEDICAL SCIENCE 2024; 41:80-85. [PMID: 38247035 DOI: 10.12701/jyms.2023.00934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 11/24/2023] [Indexed: 01/23/2024]
Abstract
BACKGROUND This study aimed to compare and evaluate the marginal fit of nanocomposite computer-aided design/computer-aided manufacturing (CAD/CAM) inlays. Three types of nanocomposite CAD/CAM blocks (HASEM, VITA Enamic, and Lava Ultimate) were used as materials. METHODS Class II disto-occlusal inlay restorations were prepared on a typodont mandibular right first molar using diamond rotary instruments. The inlays were fabricated using CAD/CAM technology and evaluated using the silicone replica technique to measure marginal gaps at five locations on each inlay. The data were analyzed by two-way analysis of variance and Tukey post hoc tests ( α=0.05). RESULTS There were no significant differences in the marginal gaps based on the type of nanocomposite CAD/CAM inlay used (p=0.209). However, there was a significant difference in the marginal gaps between the measurement regions. The gingival region consistently exhibited a larger marginal gap than the axial and occlusal regions (p<0.001). CONCLUSION Within the limitations of this in vitro study, the measurement location significantly influenced the marginal fit of class II disto-occlusal inlay restorations. However, there were no significant differences in the marginal gaps among the different types of CAD/CAM blocks. Furthermore, the overall mean marginal fits of the class II disto-occlusal inlay restorations made with the three types of nanocomposite CAD/CAM blocks were within the clinically acceptable range.
Collapse
Affiliation(s)
- Hyunsuk Choi
- Department of Dentistry and Prosthodontics, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Jae-Young Jo
- Department of Dentistry and Prosthodontics, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Min-Ho Hong
- Department of Dental Laboratory Science, College of Health Sciences, Catholic University of Pusan, Busan, Korea
| |
Collapse
|
5
|
Farghal A, Dewedar K, AbdElaziz MH, Saker S, Hassona M, Algabri R, Alqutaibi AY. Effect of ceramic materials and tooth preparation design on computer-aided design and computer-aided manufacturing endocrown adaptation and retentive strength: An in vitro study. Clin Exp Dent Res 2024; 10:e843. [PMID: 38345492 PMCID: PMC10828905 DOI: 10.1002/cre2.843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/23/2023] [Accepted: 01/04/2024] [Indexed: 02/15/2024] Open
Abstract
OBJECTIVES To evaluate how various tooth preparation designs impact the adaptation-both at the margins and internally-and the retentive strength of computer-aided design and computer-aided manufacturing (CAD/CAM) produced endocrowns. MATERIALS AND METHODS 60 extracted human mandibular first molars were endodontically treated and assigned into three groups (n = 20) according to the tooth preparation design: Group N: butt joint design, Group F and F1 received 1- and 2-mm circumferential ferrule preparation, respectively. Endocrowns were milled using either lithium disilicate glass-ceramic (IPS emax ceramic) or monolithic zirconia. The internal and marginal adaptation of the endocrowns were evaluated using the replica technique. After cementation, the endocrowns of all test groups were dislodged axially at 0.5 mm/min using a universal testing machine. A 2-way ANOVA and the independent samples t-test (α = .05) were performed to statistically analyze the data. RESULTS The effect of changing the design of the tooth preparation (butt joint, ferrule) on the marginal and internal gap was shown to be statistically significant (p < .05); the lower gap values were recorded at the axial followed by cervical, marginal, and pulpal floor walls in both ceramic groups regardless of the teeth preparation design. The ANOVA test revealed similar average removal forces and stresses for the two types of tested ceramic materials. CONCLUSION IPS emax ceramic adapted better than monolithic zirconia ceramic, regardless of the preparation design. Ferrule preparation design is more retentive than butt joint preparation, regardless of the type of ceramic material used.
Collapse
Affiliation(s)
- Ahmed Farghal
- Substitutive Dental Science, College of DentistryTaibah UniversityMadinahSaudi Arabia
| | - Karim Dewedar
- Crown and Bridge Department, Faculty of Dental MedicineAl‐Azhar UniversityCairoEgypt
| | - Mohammed H. AbdElaziz
- Substitutive Dental Science, College of DentistryTaibah UniversityMadinahSaudi Arabia
- Crown and Bridge Department, Faculty of Dental MedicineAl‐Azhar UniversityCairoEgypt
| | - Samah Saker
- Fixed Prosthodontics, Faculty of DentistryMansoura UniversityMansouraEgypt
| | - Mahy Hassona
- Fixed Prosthodontics, Faculty of DentistryMansoura UniversityMansouraEgypt
| | - Radwan Algabri
- Prosthodontic Department, Faculty of DentistryIbb UniversityIbbYemen
- Prosthodontic Department, Faculty of DentistryNational University, Ibb branchIbbYemen
| | - Ahmed Yaseen Alqutaibi
- Substitutive Dental Science, College of DentistryTaibah UniversityMadinahSaudi Arabia
- Prosthodontic Department, Faculty of DentistryIbb UniversityIbbYemen
| |
Collapse
|
6
|
Temizkan Nizaroglu R, Küçük C. Evaluation of Marginal and Internal Adaptation of Crowns Fabricated with Three Different Zirconia CAD/CAM Materials. Niger J Clin Pract 2024; 27:54-61. [PMID: 38317035 DOI: 10.4103/njcp.njcp_410_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 11/09/2023] [Indexed: 02/07/2024]
Abstract
BACKGROUND Marginal and internal adaptation are key factors that determine the clinical success of dental restorations. AIM The aim of this study is to evaluate the marginal and internal fit of crowns fabricated with three different CAD-CAM zirconia materials; two monolithic zirconia materials and one veneered zirconia copings in comparison with conventional metal-ceramic crowns. MATERIAL AND METHODS Ninety-six extracted molars (n = 96) were selected. Teeth were randomly divided into four groups (n = 24), and the following restorations were fabricated: Metal-ceramic crowns (Control group) (Group CG); monolithic zirconia crowns (GC initial) (Group MZ1); monolithic zirconia crowns (InCoris TZI),(Group MZ2); bilayered zirconia crowns, cores (InCoris ZI) veneered with a low-fusing glass-ceramic (IPS Emax Ceram),(Group BZ). Internal and marginal adaptations were evaluated using the silicone replica technique. A total of 20 points were recorded for every tooth under the light microscope at 20x magnifications. Results were compared using one-way analysis of variance (ANOVA) and the posthoc Tukey's test at a significance level of 0.01. RESULTS Marginal, marginal-internal, axial, and occlusal gaps between CG, MZ1, MZ2, and BZ crowns showed statistically significant differences (P < 0.01). CONCLUSION Monolithic zirconia groups showed better marginal adaptation compared with the veneered zirconia crowns.
Collapse
|
7
|
Ozden YE, Ozkurt-Kayahan Z, Kazazoglu E. Effect of intraoral scanning distance on the marginal discrepancy of milled interim crowns. J Prosthodont 2024; 33:41-45. [PMID: 36649200 DOI: 10.1111/jopr.13646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/24/2022] [Accepted: 01/03/2023] [Indexed: 01/18/2023] Open
Abstract
PURPOSE To compare the marginal discrepancy between milled interim crowns fabricated using intraoral digital scans acquired at different scanning distances. MATERIALS AND METHODS Ten acrylic typodont teeth were prepared for interim crowns. Three different resin frames of 2.5-, 5-, and 7.5-mm heights were fabricated and attached to an intraoral scanner (Omnicam). Three groups were created based on the different scanning distances tested: 2.5 mm (Group A), 5 mm (Group B), and 7.5 mm (Group C). Intraoral digital scans were performed on four tooth surfaces: mesial, distal, buccal, and lingual (n = 10). Each experimental scan was used to design and fabricate a milled polymethylmethacrylate anatomically contoured crown. Vinyl polyether silicone was used three times to assess the marginal discrepancy of the specimens by measuring five marginal points on digital photographs. One-way analysis of variance test was used to analyze the data, followed by Tukey's honestly significant difference test (α = 0.05). RESULTS The mean marginal discrepancy values in Group C were significantly higher than those in Groups A (p ≤ 0.000) and B (p = 0.001). There was no significant difference between Groups A and B (p = 0.702). There were no significant differences among the four surfaces in any of the scanning distance groups (p1 = 0.583, p2 = 0.390, and p3 = 0.135; p > 0.05). CONCLUSIONS The interim crowns fabricated with a scanning distance of 7.5 mm showed the greatest marginal discrepancy when compared with crowns fabricated using 2.5- and 5-mm scanning distances.
Collapse
Affiliation(s)
- Yunus Emre Ozden
- Department of Prosthodontics, Yeditepe University Faculty of Dentistry, Istanbul, Turkey
| | - Zeynep Ozkurt-Kayahan
- Department of Prosthodontics, Yeditepe University Faculty of Dentistry, Istanbul, Turkey
| | - Ender Kazazoglu
- Department of Prosthodontics, Yeditepe University Faculty of Dentistry, Istanbul, Turkey
| |
Collapse
|
8
|
Ozkan Irem D, Alpkilic DS, Isler Deger S. The effect of pre-ceramic soldering on marginal and internal fit of 4-unit zirconia frameworks and monolithic zirconia fixed dental prostheses. Odontology 2024; 112:169-176. [PMID: 37422770 DOI: 10.1007/s10266-023-00826-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 05/31/2023] [Indexed: 07/11/2023]
Abstract
The aim of this study is to evaluate the effect of pre-ceramic soldering on the marginal and internal fit of 4-unit zirconia fixed dental prostheses (FPDs) that have two abutments and two pontics. 4-unit zirconia frameworks (Zirkonzahn ICE Translucent) (Z Group) and monolithic zirconia (Zirkonzahn Prettau) (M Group) FPDs were manufactured. Groups were divided into two groups (n = 10) control (ZC and MC) and soldering (ZS and MS). Samples of ZS and MS groups were cut into two pieces under cooling water and soldered with a bonding material (DCM Zircon HotBond). The marginal and internal fit of the restorations were measured from 36 points of each sample and cement space volume was calculated using reverse engineering software (Geomagic Design X). The mean and standard deviations were submitted to Generalized Linear Mixed Model (GLMM) analysis (α = 0.05). Statistical differences between groups before and after pre-ceramic soldering on point measurements were found. In total cement spacing measurements, a significant difference was found amongst all groups (P < 0.05). However, in premolars, a statistically significant difference was found between ZC and ZS groups and MC and MS groups (P < 0.05). All discrepancies after pre-ceramic soldering were found to be lower than before.
Collapse
Affiliation(s)
| | - Dilara Seyma Alpkilic
- Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Beyazit Yerleşkesi, Beyazit, 34452, Istanbul, Turkey.
| | - Sabire Isler Deger
- Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Beyazit Yerleşkesi, Beyazit, 34452, Istanbul, Turkey
| |
Collapse
|
9
|
Sun Z, Shen Z, Zhao J, Zheng Y. Adaptation and uniformity of monolithic zirconia crowns fabricated by additive 3-dimensional gel deposition. J Prosthet Dent 2023; 130:859-865. [PMID: 35135676 DOI: 10.1016/j.prosdent.2021.11.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 12/13/2022]
Abstract
STATEMENT OF PROBLEM A novel monolithic zirconia restoration fabricated by additive 3-dimensional (3D) gel deposition, named as self-glazed zirconia (SGZ), has recently been developed. SGZ crowns exhibit reliable mechanical properties and esthetic appearance, but their adaptation and uniformity are unclear. PURPOSE The purpose of this in vitro study was to compare the adaptation and uniformity of monolithic zirconia crowns fabricated by additive 3D gel deposition with that of milled zirconia and lithium disilicate crowns. MATERIAL AND METHODS Ten identical resin abutments were made based on the scanning data of an extracted and prepared human mandibular first molar. Three types of monolithic crowns were then fabricated by using 2 different processes: 3D gel deposition zirconia (SGZ), milled zirconia (ZZ), and milled lithium disilicate (EMX) (n=10) through a completely digital workflow. The nondestructive direct-view technique and replica technique were used to measure the marginal and internal discrepancy values individually. The uniformity index was calculated to describe the uniformity of the internal space. The results were analyzed by using 1-way ANOVA and Kruskal-Wallis statistical tests (α=.05). RESULTS The marginal discrepancy of EMX exhibited the highest values among the 3 groups (P=.001). The 2 types of zirconia crowns had comparable marginal discrepancy values (P>.05). The internal discrepancy values of SGZ were significantly lower than those of EMX at the occlusal region and of ZZ at all measured locations (P<.05). All 3 types of monolithic crowns showed comparable good uniformity (P=.056). CONCLUSIONS The marginal and internal adaptations of novel monolithic zirconia crowns were within clinical requirements. Compared with the zirconia and lithium disilicate crowns fabricated by subtractive milling, monolithic zirconia crowns fabricated by additive 3D gel deposition had comparable uniformity and better internal adaptation.
Collapse
Affiliation(s)
- Zhe Sun
- Practicing Physician, Department of General Dentistry, School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, PR China
| | - Zhenyu Shen
- Graduate student, Graduate Prosthodontics, School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, PR China
| | - Jing Zhao
- Attending Physician, Department of General Dentistry, Stomatological Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, PR China
| | - Yuanna Zheng
- Associate Professor, School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, PR China.
| |
Collapse
|
10
|
Liang S, Yuan F, Li D, Jia L, Sun Y. Digital measurement method for comparing the absolute marginal discrepancy of three-unit ceramic fixed dental prostheses fabricated using conventional and digital technologies. BMC Oral Health 2023; 23:880. [PMID: 37978507 PMCID: PMC10657126 DOI: 10.1186/s12903-023-03620-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 11/03/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND In clinical practice, control of the marginal fit of fixed dental prostheses is hindered by evaluation method, which needs to be further improved to increase its clinical applicability. This study aimed to quantitatively analyze the absolute marginal discrepancy of three-unit ceramic fixed dental prostheses fabricated by conventional and digital technologies using a digital measurement method based on the digital impression technology and open source software. METHODS A digital workflow and the conventional impression combined with the lost-wax heat-pressed technique were adopted to separately fabricate 10 glass ceramic fixed dental prostheses. Three-dimensional data for the abutments, fixed dental prostheses, and fixed dental prostheses seated on the abutments, were obtained using a dental scanner. The two datasets were aligned using registration technology, specifically "multi-points registration" and "best fit alignment," by reverse engineering software. Subsequently, the three-dimensional seated fit between the fixed dental prostheses and abutments were reconstructed. The margin of the abutment and crown was extracted using edge-sharpening and other functional modules, and the absolute marginal discrepancy was measured by the distance between the margin of the abutment and crown. One-way analysis of variance was used to statistically analyze the measurement results. RESULTS Using the digital measurement method, the mean value of absolute marginal discrepancy for fixed dental prostheses fabricated by the conventional method was 106.69 ± 6.46 μm, and that fabricated by the digital workflow was 102.55 ± 6.96 μm. The difference in the absolute marginal discrepancy of three-unit all-ceramic fixed dental prostheses fabricated using the two methods was not statistically significant (p > 0.05). CONCLUSIONS The digital measurement method for absolute marginal discrepancy was preliminarily established based on open source software and applied in three-unit ceramic fixed dental prostheses. The absolute marginal discrepancy of three-unit ceramic fixed dental prostheses fabricated using digital technology was comparable to that of conventional technique.
Collapse
Affiliation(s)
- Shanshan Liang
- Center of Digital Dentistry/Department of Prosthodontics/Second Clinical Division, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases &National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, Beijing, 100081, People's Republic of China
| | - Fusong Yuan
- Center of Digital Dentistry/Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases &National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, Beijing, 100081, People's Republic of China
| | - Deli Li
- Second Clinical Division, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology, Beijing, 100081, People's Republic of China
| | - Lu Jia
- Denture Processing Center, Peking University School and Hospital of Stomatology, & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology, Beijing, 100081, People's Republic of China
| | - Yuchun Sun
- Center of Digital Dentistry/Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases &National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, Beijing, 100081, People's Republic of China.
| |
Collapse
|
11
|
Loetzerich JM, Raith S, Reich S. Verification of a digital approach for three-dimensional evaluation of marginal and internal fit. J Prosthet Dent 2023:S0022-3913(23)00618-2. [PMID: 37852857 DOI: 10.1016/j.prosdent.2023.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 10/20/2023]
Abstract
STATEMENT OF PROBLEM Internal fit is an important aspect of indirect restorations, but methods for the 3-dimensional (3D) measurement of absolute marginal and intaglio fit are sparse. PURPOSE The purpose of this in vitro study was to evaluate an innovative 3D measurement method (AIXFit) based on intraoral scanning data for analyzing the fit of dental restorations. MATERIAL AND METHODS For the evaluation of AIXFit, 12 monolithic zirconia crowns were fabricated on typodont preparations. The fit was measured digitally with the AIXFit system and compared with the results obtained from an established 2-dimensional (2D) sectional procedure. To compare the values of both methods at identical locations, a common reference system was developed, with each die fixed in a gypsum stand with reference points. Using an intraoral scanner (True Definition), each die with its reference points and the intaglio surface of the finished crown were digitalized as standard tessellation language files. The AIXFit software program, with a specially developed best-fit algorithm, was used to match the intaglio surface of the crown with the surface of the preparation. The virtual cement gap was calculated over the entire surface and returned values for x≥0 µm. A 2D comparison method involved adhesively fixing the crown to the die and sectioning it into 4 parts with a diamond band saw. The thickness of the cement gap was determined under a light microscope at ×100 magnification at 5 defined measuring points per quarter, so that a total of 240 measurements were available for comparison. A software program (Blender Foundation) was used to superimpose the data from the AIXFit system with the data from the 2D method and to compare the cement gaps at the same locations. The agreement between these methods was verified using paired t tests and determine correlation coefficients (α=.05). RESULTS The mean ±standard deviation difference between the AIXFit and 2D methods was 6.7 ±29 µm). Two 1-sided tests showed statistical equivalence between the methods of measurement when considering an interval between -20 and +20 µm. The correlation coefficients showed a positive association for both methods (r=.931). CONCLUSIONS The AIXFit software program appeared to be accurate for the digital measurement of internal fit when using the True Definition scanner. It enabled a cast-free workflow and allowed the analysis of the entire intaglio surface.
Collapse
Affiliation(s)
- Jan Markus Loetzerich
- Graduate student, Department of Prosthodontics and Biomaterials, Centre of Implantology, University Hospital RWTH Aachen, Aachen, Germany.
| | - Stefan Raith
- Research Assistant, Department of Prosthodontics and Biomaterials, Centre of Implantology, University Hospital RWTH Aachen, Aachen, Germany
| | - Sven Reich
- Professor, Department of Prosthodontics and Biomaterials, Centre of Implantology, University Hospital RWTH Aachen, Aachen, Germany
| |
Collapse
|
12
|
Nawafleh N, Hatamleh M, Janzeer Y, Alrahlah A, Alahadal K. Marginal Discrepancy of Five Contemporary Dental Ceramics for Anterior Restorations. Eur J Dent 2023; 17:1114-1119. [PMID: 36599451 PMCID: PMC10756837 DOI: 10.1055/s-0042-1758787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
OBJECTIVES This study aimed to compare marginal accuracy of five contemporary all-ceramic crowns indicated for anterior restorations. MATERIALS AND METHODS A master die of maxillary central incisor was prepared for all-ceramic crown and duplicated to produce 50 replicas of epoxy resin material. Five ceramic materials were used to mill the crowns (n = 10). All crowns were manufactured following the same digital workflow; same master die, scanning unit and design software, and the recommended manufacturing protocol. Final seating of crown was secured by a small droplet of temporary cement on its incisal edge. Marginal accuracy was evaluated by scanning electronic microscope with a magnification of 300 × . Vertical marginal gap was measured for each crown at predefined four points. STATISTICAL ANALYSIS One-way analysis of variance was used to test differences between groups and Tukey test was used for multiple comparisons between group combinations. A level of significance at 95% was set for all statistics. RESULTS The highest mean marginal gap and mean maximum gap calculated were for the e.max CAD crowns (49.2 µm, 87.6 µm), while the lowest values were for the Cercon xt crowns (10.2 µm, 21.7 µm). The mean marginal gap and the mean maximum gap of the e.max CAD crowns were statistically significantly greater than those of all other groups (p < 0.05). However, the differences between all other combinations were insignificant (p > 0.05). CONCLUSION Marginal accuracy of lithium disilicate crowns is clinically acceptable. Zirconia and zirconia-reinforced lithium silicate materials can produce a greater level of marginal accuracy compared to lithium disilicate.
Collapse
Affiliation(s)
- Noor Nawafleh
- Department of Applied Dental Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Irbid, Jordan
| | - Muhanad Hatamleh
- Department of Applied Medical Sciences, Luminus Technical University College, Amman, Jordan
| | - Yasmeen Janzeer
- Department of Applied Dental Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Irbid, Jordan
| | - Ali Alrahlah
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
- Restorative Dental Sciences Department, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Khold Alahadal
- Restorative Dental Sciences Department, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| |
Collapse
|
13
|
Emam M, Metwally MF. Effect of coping materials zirconia or polyetheretherketone with different techniques of fabrication on vertical marginal gap and fracture resistance of posterior crowns with composite veneering. BMC Oral Health 2023; 23:546. [PMID: 37559037 PMCID: PMC10413631 DOI: 10.1186/s12903-023-03247-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 07/21/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND Insufficient research has been conducted in the literature assessing the performance of zirconia and polyetheretherketone (PEEK) crowns in relation to the essential requirements of successful restorations, such as fracture resistance or margin adaptation. The purpose of this study was to evaluate the effect of the coping materials zirconia or PEEK with different fabrication techniques on the vertical marginal gap and fracture resistance of posterior crowns with composite veneering. METHODS Ceramic copings (n = 18) restoring mandibular first molar were fabricated from zirconia (Zircon.x, Presidentdental, Germany), milled PEEK (PEEK CAD) (breCAM.BioHPP, Bredent, Germany) and pressed PEEK (PEEK Press) (BioHPP Granules, Bredent, Germany) six specimens each (n = 6). The copings were veneered with high impact polymer composite (HIPC) material (breCAM.HIPC, Bredent, Germany). The vertical marginal gap was captured under a magnification of 40X. Five equidistant marks on each surface of the die distinguished the points of measurement for a total of 20 readings per sample. The analysis was completed using an image analysis system (ImageJ 1.53t, National Institute of Health, USA). The specimens were loaded to failure at a crosshead speed of 1 mm/min and the load at failure was recorded to measure the fracture resistance. RESULTS The marginal gap was analyzed using one-way ANOVA followed by Tukey's post hoc test. Fracture resistance was analyzed using Welch one-way ANOVA followed by the Games-Howell post hoc test. Marginal gap values showed a significant difference between the tested groups, with zirconia having significantly lower gap values (48.67 ± 11.98 µm) than both the PEEK CAD (108.00 ± 20.08 µm) and Press groups (108.00 ± 25.10 µm) (p < 0.001). However, the results of fracture resistance showed no significant difference (p = 0.06) with 1687.47 ± 253.29 N, 2156.82 ± 407.64 N, 2436.72 ± 725.93 N for zirconia, PEEK CAD, and Press, respectively. The significance level was p < 0.05. CONCLUSIONS Zirconia framework crowns have a smaller vertical marginal gap than milled and pressed PEEK crowns. Crowns fabricated from zirconia, PEEK CAD, or PEEK Press frameworks and veneered with composite resin have comparable fracture resistance lower than the maximum biting force in the posterior region. CLINICAL RELEVANCE Posterior crowns with zirconia frameworks are preferred over milled and pressed PEEK frameworks regarding margin adaptation, although all can safely survive the maximum occlusal forces without fracture.
Collapse
Affiliation(s)
- Marwa Emam
- Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Organization of African Unity St, El-Qobba Bridge, Al Waili, 11566, Cairo, Egypt.
| | - Mohamed F Metwally
- Department of Crown and Bridge, Faculty of Dental Medicine, AL Azhar University, Cairo, Egypt
| |
Collapse
|
14
|
Di Fiore A, Zuccon A, Carraro F, Basilicata M, Bollero P, Bruno G, Stellini E. Assessment Methods for Marginal and Internal Fit of Partial Crown Restorations: A Systematic Review. J Clin Med 2023; 12:5048. [PMID: 37568450 PMCID: PMC10419640 DOI: 10.3390/jcm12155048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023] Open
Abstract
BACKGROUND Different methods are used for the analysis of marginal and internal fit of partial crowns, but not all of them are applicable for in vivo studies. The aim of this review is to search the available methods, described in the current literature, to assess marginal and internal fit in partial crowns. METHODS an electronic search was performed on Pubmed and Web of Science databases to find studies published from 1 January 2017 up to 2 March 2023, following PRISMA guidelines and Cochrane handbook for systematic reviews. The search strategy applied was: "(marginal) AND (fit OR gap OR adaptation OR discrepancy) AND (inlay OR onlay OR partial crown)". In vitro studies which evaluated marginal and internal fit on CAD CAM or 3D printed partial crowns were included in this review. Quality of the studies was assessed by using Quality Assessment Tool For In Vitro Studies (QUIN tool). RESULTS 22 studies were included. Among conventional methods, direct view with microscope, indirect view on resin replicas, and silicone replica technique (SRT) were used. Considering new digital methods, micro-CT, SRT 3D and triple scan technique (TST) were applied. CONCLUSIONS Among 2D methods, direct view technique is the most used marginal fit analysis. For a more comprehensive evaluation, a 3D digital analysis is suggested. SRT and indirect view are the only 2D methods available for in vivo analysis. A protocol for the application of TST for assessment in vivo is now available, but no studies are reported in literature yet.
Collapse
Affiliation(s)
- Adolfo Di Fiore
- Department of Neuroscience, Section of Prosthetic and Digital Dentistry, University of Padova, 35122 Padova, Italy; (A.Z.); (G.B.); (E.S.)
| | - Andrea Zuccon
- Department of Neuroscience, Section of Prosthetic and Digital Dentistry, University of Padova, 35122 Padova, Italy; (A.Z.); (G.B.); (E.S.)
| | - Filippo Carraro
- Department of Neuroscience, Section of Prosthetic and Digital Dentistry, University of Padova, 35122 Padova, Italy; (A.Z.); (G.B.); (E.S.)
| | - Michele Basilicata
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Roma, Italy; (M.B.); (P.B.)
| | - Patrizio Bollero
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Roma, Italy; (M.B.); (P.B.)
| | - Giovanni Bruno
- Department of Neuroscience, Section of Prosthetic and Digital Dentistry, University of Padova, 35122 Padova, Italy; (A.Z.); (G.B.); (E.S.)
| | - Edoardo Stellini
- Department of Neuroscience, Section of Prosthetic and Digital Dentistry, University of Padova, 35122 Padova, Italy; (A.Z.); (G.B.); (E.S.)
| |
Collapse
|
15
|
Hennig CL, Stöcker A, Nitzsche A, Marquetand J, Jacobs C, Jahn F. Influence of Root Post Materials and Aging on Fracture Strength and Marginal Gap Quality of Ceramic Crowns-An In Vitro Study. MATERIALS (BASEL, SWITZERLAND) 2023; 16:ma16113985. [PMID: 37297118 DOI: 10.3390/ma16113985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/22/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023]
Abstract
The design of and materials for prosthodontic abutments and posts have significant influences on the fracture resistance of restored teeth. This in vitro study compared the fracture strength and marginal quality of full-ceramic crowns as a function of the inserted root posts via simulation of a five-year period of use. Test specimens were prepared from 60 extracted maxillary incisors using titanium L9 (A), glass-fiber L9 (B), and glass-fiber L6 (C) root posts. The circular marginal gap behavior, linear loading capacity, and material fatigue after artificial aging were investigated. The marginal gap behavior and material fatigue were analyzed using electron microscopy. The linear loading capacity of the specimens was investigated using the Zwick Z005 universal testing machine. None of the tested root post materials showed statistically significant differences in marginal width values (p = 0.921), except in the case of marginal gap location. For Group A, there was a statistically significant difference from the labial to the distal (p = 0.012), mesial (p = 0.000), and palatinal (p = 0.005). Similarly, Group B showed a statistically significant difference from the labial to the distal (p = 0.003), mesial (p = 0.000), and palatinal (p = 0.003). Group C showed a statistically significant difference from the labial to the distal (p = 0.001) and mesial (p = 0.009). Linear load capacity reached mean values of 455.8-537.7 N, and micro-cracks occurred after artificial aging, predominantly in Groups B and C. Through the chosen experimental design, it was shown that the root post material and root post length had no influence on the fracture strength of the test teeth before or after artificial aging. However, the marginal gap location depends on the root post material and its length, which is wider mesially and distally and also tends to be greater palatinally than labially.
Collapse
Affiliation(s)
- Christoph-Ludwig Hennig
- Department of Orthodontics, Center of Dental Medicine, University Hospital Jena, An der alten Post 4, 07743 Jena, Germany
| | - André Stöcker
- Section of Geriodontics, Department of Conservative Dentistry and Periodontology, Center of Dental Medicine, University Hospital Jena, An der alten Post 4, 07743 Jena, Germany
| | - Ann Nitzsche
- Department of Orthodontics, Center of Dental Medicine, University Hospital Jena, An der alten Post 4, 07743 Jena, Germany
| | - Justus Marquetand
- Department of Epileptology, Hertie-Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany
- Department of Neural Dynamics and Magnetoencephalography, Hertie-Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany
- MEG-Center, University of Tübingen, 72076 Tübingen, Germany
| | - Collin Jacobs
- Department of Orthodontics, Center of Dental Medicine, University Hospital Jena, An der alten Post 4, 07743 Jena, Germany
| | - Florentine Jahn
- Section of Geriodontics, Department of Conservative Dentistry and Periodontology, Center of Dental Medicine, University Hospital Jena, An der alten Post 4, 07743 Jena, Germany
| |
Collapse
|
16
|
Attia MA, Blunt L, Bills P, Tawfik A, Radawn M. Micro-CT analysis of marginal and internal fit of milled and pressed polyetheretherketone single crowns. J Prosthet Dent 2023:S0022-3913(23)00183-X. [PMID: 37072286 DOI: 10.1016/j.prosdent.2023.03.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 04/20/2023]
Abstract
STATEMENT OF PROBLEM Polyetheretherketone (PEEK) has been increasingly used as a framework material in prosthetic dentistry. However, data on the marginal and internal fit of PEEK restorations fabricated by using either the computer-aided design and computer-aided manufacturing (CAD-CAM) or heat-pressing technique are sparse. PURPOSE The aim of this in vitro study was to assess the marginal and internal fit of milled and pressed PEEK single crowns by using microcomputed tomography (μCT). MATERIAL AND METHODS A custom-made, single stainless-steel die was designed to replicate a maxillary first premolar prepared for a ceramic crown. PEEK copings (N=30) were fabricated and allocated to 3 groups (n=10) according to the fabrication technique: milled from a prefabricated PEEK blank, heat pressed from PEEK pellets, and heat pressed from PEEK granules. All copings were veneered with a composite resin material. The marginal fit was recorded at 4 predetermined points and the internal fit at 8 predetermined points on each crown by using μCT. Two-way ANOVA, pair-wise Tukey honestly significant difference (HSD), and simple main effect tests were used for statistical analysis of the data (α=.05). RESULTS Concerning marginal fit, the milled crowns demonstrated the best marginal fit overall (44 ±3 μm), followed by those pressed from pellets (92 ±3 μm), and finally by those pressed from granules (137 ±7 μm) (P<.001). The interaction between the effects of the fabrication technique and the measurement point on the marginal fit was not statistically significant (P=.142). The milled crowns demonstrated the lowest mean gap values overall, followed by those pressed from pellets and those pressed from granules (P<.001). The interaction between the effects of the fabrication technique and the measurement point on the internal fit was statistically significant (P<.001). Except for the distal occlusal gap and mesial occlusal gap, all tested groups showed a statistically significant difference (P<.001). In addition, statistically significant differences were observed among all measurement points in different fabrication techniques (P<.001). CONCLUSIONS The marginal and internal fit of milled PEEK crowns was significantly better than pressed crowns. However, both CAD-CAM and heat-pressing techniques produced PEEK crowns with a clinically acceptable marginal and internal fit. The mean marginal gap of the PEEK crowns pressed from granules was above the range of clinically acceptable value.
Collapse
Affiliation(s)
- Mazen A Attia
- Associate Professor, Department of Fixed Prosthodontics, Faculty of Dentistry, Beni-Suef University, Beni-Suef, Egypt.
| | - Liam Blunt
- Professor, EPSRC Future Advanced Metrology Hub, University of Huddersfield, Huddersfield, United Kingdom
| | - Paul Bills
- Professor, EPSRC Future Advanced Metrology Hub, University of Huddersfield, Huddersfield, United Kingdom
| | - Ahmed Tawfik
- PhD Researcher, EPSRC Future Advanced Metrology Hub, University of Huddersfield, Huddersfield, United Kingdom
| | - Mohamed Radawn
- Lecturer, Department of Fixed Prosthodontics, Faculty of Dentistry, Beni-Suef University, Beni-Suef, Egypt
| |
Collapse
|
17
|
Toma FR, Moleriu LC, Porojan L. Micro-CT Marginal and Internal Fit Evaluation of CAD/CAM High-Performance Polymer Onlay Restorations. Polymers (Basel) 2023; 15:polym15071715. [PMID: 37050329 PMCID: PMC10096728 DOI: 10.3390/polym15071715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/20/2023] [Accepted: 03/27/2023] [Indexed: 04/14/2023] Open
Abstract
(1) Background: The use of high-performance polymers for fixed restorations requires additional studies regarding their adaptability and processing with CAD/CAM technology. This in vitro study aims to assess the marginal and internal fit of PEEK and PEKK materials using microcomputed tomography. (2) Methods: Twenty-four (n = 8) MOD onlays made of PEKK (Pekkton ivory), unmodified PEEK (Juvora medical), and modified PEEK (BioHPP) were investigated. A typodont mandibular left first molar was scanned to achieve 24 resin, 3D printed abutment teeth. The onlays were fabricated with a five-axis milling machine, and after cementation of the specimens, the marginal (MG) and internal gaps (IG) were evaluated at twelve points in the mesio-distal section and thirteen points in the bucco-lingual section using microcomputed tomography. For statistical data analysis, Wilcoxon signed-rank/paired Student t-Test, Mann-Whitney/unpaired Student t-Test, and one-way ANOVA test were applied. (3) Results: Significant differences (p < 0.05; α = 0.05) were reported between the MG and IG for each material for all three polymers and also among two materials in terms of the MG and IG (except Juvora-BioHPP). The highest IG values were recorded in angular areas (axio-gingival line angle) in the mesio-distal section for all the polymers. (4) Conclusions: For all the materials, MG < IG. The type of polymer influenced the adaptability; the lowest marginal and internal gap mean values were recorded for BioHPP. The analyzed polymer used for onlays are clinically acceptable in terms of adaptability.
Collapse
Affiliation(s)
- Flavia Roxana Toma
- Department of Dental Prostheses Technology (Dental Technology), Center for Advanced Technologies in Dental Prosthodontics, Faculty of Dental Medicine, "Victor Babeș" University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timisoara, Romania
| | - Lavinia Cristina Moleriu
- Department of Functional Science, "Victor Babeș" University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timisoara, Romania
| | - Liliana Porojan
- Department of Dental Prostheses Technology (Dental Technology), Center for Advanced Technologies in Dental Prosthodontics, Faculty of Dental Medicine, "Victor Babeș" University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timisoara, Romania
| |
Collapse
|
18
|
Alsubaiy EF. Micro-CT analysis of 3D printed provisional crowns fitting. Technol Health Care 2023; 31:259-268. [PMID: 36057803 DOI: 10.3233/thc-220304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND The provisional crowns (PR) play an important role during the course of fixed prosthesis treatment. The fitting of PR varies and depends on various factors. OBJECTIVE The aim of the study was to evaluate the marginal and internal fit of PR produced by three-dimensional (3D) printing technique and to compare those with PR made by the milling technique by using micro computed tomography (μCT) on three commonly used finish line designs. METHOD Ninety study models were made using metal die of #14 tooth (i.e. maxillary 1st premolar molar) prepared for full veneer crown with three different finish line chamfer (C), rounded shoulder (RS) and rounded shoulder with bevel (RSB). PR was fabricated on each study model, using milling (MiL group, n= 45), and 3D printing technique (3D-P group, n= 45). Marginal and internal fit of each study model was measured by micro computed tomography, at 7 Zones Pr-1- Pr-7 on each finish line. Recorded data were statistically analysed by one-way analysis of variance (ANOVA) and using Dunnett t-Test (p> 0.05). RESULTS The mean gap at margins was minimum for provisional crowns in 3D-P group in any finish line with minimum in rounded shoulder with bevel at zone Pr-1 30.9 ± 5.3 and at zone Pr-7 32.7 ± 5.3. In the axial region, i.e. zone Pr-2, the smallest gap was recorded in the 3D-P group and in the occlusal region, for zone Pr-3, 4 and 5, the maximum gap was recorded in the MiL group. CONCLUSION The provisional crowns fabricated by 3D printed technique have better marginal and internal fit than the provisional crowns made by milling technique.
Collapse
|
19
|
Albayrak H, Eraslan R, Temizkanli O, Sahin BS, Ayata M, Sezer T. The Effect of Sintering Procedures on Fit and Color in Zirconia Crowns. JOURNAL OF ADVANCED ORAL RESEARCH 2022. [DOI: 10.1177/23202068221129025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Purpose: The aim of this study was to examine the effects of various sintering procedures on the color parameters, marginal, and internal fit of zirconia crowns. Materials and Methods: Overall, 60 zirconia crowns were produced using 3 distinct zirconia blocks (Wieland Zenostar, Zirkonzahn Ice Translucent, and Zirkonzahn Prettau). For the sintering procedure of the crowns, six groups were created as follows: Wieland-Standard, Wieland-Speed, Ice-Standard, Ice-Speed, Prettau-Slow, and Prettau-Standard programs. The crowns were assigned into groups ( n = 10 in each group). The color parameters, marginal fit, and internal fit of the crowns were evaluated. The normality of data distribution was evaluated with the Kolmogrov–Smirnov test. Two independent samples t-test and Mann–Whitney U test were used to compare the sintering groups. Results: Acceleration of sintering caused a significant change in the color parameters of the Wieland and Ice groups but not in the Prettau group. In the Wieland group, marginal ( p = .047) and internal ( p = .004) gap values of speed sintering were found to be significantly lower than those in standard sintering. In the Ice group, the marginal gap values of speed sintering were found to be significantly lower than those in standard sintering ( p = .019). In the Prettau group, the marginal gap values of standard sintering were found to be significantly higher ( p = .035) than those in slow sintering. Conclusions: It was concluded that the effects of sintering procedures on color parameters, and internal and marginal fit of zirconia crowns were clinically insignificant. Speed sintering can be recommended for zirconia restorations.
Collapse
Affiliation(s)
- Haydar Albayrak
- Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| | - Ravza Eraslan
- Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| | | | | | | | - Taygun Sezer
- Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| |
Collapse
|
20
|
Camargo B, Willems E, Jacobs W, Van Landuyt K, Peumans M, Zhang F, Vleugels J, Van Meerbeek B. 3D printing and milling accuracy influence full-contour zirconia crown adaptation. Dent Mater 2022; 38:1963-1976. [DOI: 10.1016/j.dental.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 09/26/2022] [Accepted: 11/07/2022] [Indexed: 11/19/2022]
|
21
|
Kassis C, Mehanna C, Khoury P, Tohme H, Cuevas-Suárez CE, Bourgi R, Lukomska-Szymanska M, Hardan L. Triple scan evaluation of internal and marginal adaptation of overlays using different restorative materials. J ESTHET RESTOR DENT 2022; 35:493-500. [PMID: 36260931 DOI: 10.1111/jerd.12977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 09/26/2022] [Accepted: 10/06/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Problems in the confection of indirect restorations may increase the marginal and internal gap. This study aimed to quantify the marginal and the internal fit of overlays fabricated with three different materials. MATERIALS AND METHODS Standardized cavities were prepared on endodontically treated human third molars and digital impressions were done using an intraoral camera (Trios 3). Restorations were designed (n = 15) and fabricated with three materials: Hybrid ceramic (Cerasmart; GC Corp, EUROPE), high-strength lithium disilicate (GC Initial® LiSi Press; GC Corp, Tokyo, Japan), and zirconia reinforced Lithium Silicate Glass Ceramic (Vita Suprinity; Vita, Germany). Axial, marginal, pulpal, and gingival gaps were calculated by measuring the distance between the restoration and the tooth at several reference points. Two-Way analysis of variance was used for statistical analysis. The significance level was set at α = 0.05. RESULTS Mean gap was significantly influenced by the material (p < 0.001), gap localization (p < 0.001), and interaction between the factors (p = 0.002). For all materials, the highest gap was observed at gingival and pulpal surfaces (p ≤ 0.015). LiSi Press achieved the overall lowest values at axial values measurements (p ≤ 0.003). CONCLUSIONS The performance of a CAD/CAM system relative to marginal adaptation is influenced by the restorative material used. High-strength lithium disilicate seems to be showed the best marginal adaptation. CLINICAL SIGNIFICANCE Marginal and internal adaptation of CAD/CAM restorations could be influenced by the type of material chosen.
Collapse
Affiliation(s)
- Cynthia Kassis
- Department of Esthetic and Restorative Dentistry, School of Dentistry, St Joseph University, Beirut, Lebanon
| | - Carina Mehanna
- Department of Esthetic and Restorative Dentistry, School of Dentistry, St Joseph University, Beirut, Lebanon
| | - Pierre Khoury
- Department of Prosthodontics, School of Dentistry, Lebanese University, Beirut, Lebanon
| | - Hani Tohme
- Digital Unit, School of Dentistry, St Joseph University, Beirut, Lebanon
| | - Carlos Enrique Cuevas-Suárez
- Dental Materials Laboratory, Academic Area of Dentistry, Autonomous University of Hidalgo State, San Agustín Tlaxiaca, Hidalgo, Mexico
| | - Rim Bourgi
- Department of Esthetic and Restorative Dentistry, School of Dentistry, St Joseph University, Beirut, Lebanon
| | | | - Louis Hardan
- Department of Esthetic and Restorative Dentistry, School of Dentistry, St Joseph University, Beirut, Lebanon
| |
Collapse
|
22
|
Tan YY, Ho TK, Goo CL. Effect of training on time efficiency and marginal adaptation of computer-aided design/computer-aided manufacturing crowns among dental students. EUROPEAN JOURNAL OF DENTAL EDUCATION : OFFICIAL JOURNAL OF THE ASSOCIATION FOR DENTAL EDUCATION IN EUROPE 2022; 26:468-474. [PMID: 34541757 DOI: 10.1111/eje.12722] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/14/2021] [Accepted: 07/10/2021] [Indexed: 06/13/2023]
Abstract
INTRODUCTION The computer-aided design/computer-aided manufacturing (CAD/CAM) technology has revolutionised dentistry at present. An operator's skills can affect the overall clinical duration and marginal accuracy of the prosthesis fabricated through this workflow. The aim of this study was to assess the effect of CAD/CAM hands-on training compared with that of a self-instructional video on the performance of dental students in digital impression and fabrication of a CAD/CAM crown. METHODS In this cross-sectional study, 30 undergraduate dental students were shown a CEREC demonstration video. Each operator then captured a digital impression using the intra-oral scanner, and a crown was subsequently milled. All participants underwent a training course before repeating the process. Marginal discrepancy for each crown on its abutment tooth was measured before and after training using a stereomicroscope and was evaluated using Wilcoxon signed rank test. The duration taken for the process was recorded before and after training and evaluated using paired t-test. RESULTS The overall mean ±standard deviation marginal adaptation for the CEREC crowns was 78.15 ± 42.83 μm before training and 52.41 ± 17.12 μm after training. The Wilcoxon signed rank test found significant difference (p < .05) in terms of marginal adaptation of crowns fabricated before and after training. Paired t-tests showed that the time efficiency after training significantly improved compared with that before training. CONCLUSIONS Training with guided feedback is crucial to improve the time efficiency of making a digital impression and marginal adaptation of fixed prosthesis using the CAD/CAM technology.
Collapse
Affiliation(s)
- Ying Yin Tan
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Ting Khee Ho
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Chui Ling Goo
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| |
Collapse
|
23
|
Mounajjed R, Taylor T, Hamadah O, Voborná I, Al-akkad M. Assessment of the readiness of restorations manufactured by CAD/CAM in terms of marginal fit (Part I). PeerJ 2022; 10:e13280. [PMID: 35529489 PMCID: PMC9070325 DOI: 10.7717/peerj.13280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 03/24/2022] [Indexed: 01/13/2023] Open
Abstract
Background The master cast is the gold standard for the control and eventual adjustment of restorations produced by conventional procedures. Some digital workflow bypasses the master cast and relies completely on the precision of the CAD/CAM restoration. Aim To examine the reproducibility of the margins of CAD/CAM restorations generated from a single digital scan. Also, to check the readiness of these restorations for delivery directly after fabrication without adjustment on a master cast and thereby eliminate the need for the master cast. Methods A total of 18 metal substructures made from cobalt chrome alloy were fabricated utilizing a single STL file. The circumference was divided into eight zones. The vertical marginal discrepancy (VMD) was measured at each zone of each metal substructure, with optical microscopy at ×200 magnification. Results Measurements of vertical marginal discrepancy were in a range of (-94: 300) with a mean of 62 ± 60 μm. A one-way ANOVA test revealed that the mean VMD is significantly different among the 18 substructures (F17, 1,134 = 63.948, p < 0.001). Conclusion Although all the received substructures were fabricated from the same scan file, they were not identical and varied widely, and they were going outside the acceptable range in some zones. Within the limitations of this study, the marginal fit can be improved by extraoral adjustments on the master cast. Thus, skipping the master cast deprives the dentist of delivering a restoration of higher quality.
Collapse
Affiliation(s)
- Radek Mounajjed
- DCM Clinic, Hradec Kralove, Czech Republic,Institute of Dentistry and Oral Sciences, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Thomas Taylor
- Department of Reconstructive Sciences, UConn School of Dental Medicine, Farmington, Connecticut, United States of America
| | - Omar Hamadah
- Department of Oral Medicine, Faculty of Dental Medicine, Damascus University, Damascus, Syria
| | - Iva Voborná
- Institute of Dentistry and Oral Sciences, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Marwan Al-akkad
- Institute of Dentistry and Oral Sciences, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| |
Collapse
|
24
|
Sidhom M, Zaghloul H, Mosleh IES, Eldwakhly E. Effect of Different CAD/CAM Milling and 3D Printing Digital Fabrication Techniques on the Accuracy of PMMA Working Models and Vertical Marginal Fit of PMMA Provisional Dental Prosthesis: An In Vitro Study. Polymers (Basel) 2022; 14:polym14071285. [PMID: 35406159 PMCID: PMC9003362 DOI: 10.3390/polym14071285] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 03/13/2022] [Accepted: 03/15/2022] [Indexed: 02/01/2023] Open
Abstract
Background: Minimal evidence exists on the efficacy of different digital manufacturing techniques in the fabrication of precise dental working models and provisional prosthesis. Aim of study: The objective was to evaluate the effect of two digital fabrication techniques (CAD/CAM milling and 3D printing) on the accuracy of PMMA working models and marginal fit of PMMA provisional prosthesis. Materials and methods: Two abutment teeth of modified typodont were prepared. A reference stone model was fabricated, and an optical impression was performed to obtain a CAD reference model. Four CAM milled working models and four printed working models were fabricated. CAD software was used to design the provisional prostheses. Group A tested four milled provisional prosthesis, and group B tested four 3D printed prosthesis. The 3D accuracy of working models was assessed by superimposition of the control reference working model on the CAD test working model. A stereo-optical microscope was used to assess vertical marginal fit of the provisional dental prosthesis. Student’s t and Mann–Whitney U tests were utilized to compare the two groups. Results: Results showed no statistically significant difference between the two tested groups. Conclusion: The two digital working model fabrication techniques recorded comparable accuracy. Similarly, 3D printed provisional prosthesis showed comparable marginal fit to the CAD/CAM milled ones.
Collapse
Affiliation(s)
- Marina Sidhom
- Fixed Prosthodontics Department, Faculty of Oral and Dental Medicine, Misr International University, Cairo 12677, Egypt;
| | - Hanaa Zaghloul
- Conservative Dentistry, Faculty of Oral & Dental Medicine, Misr International University, Cairo 12677, Egypt;
| | - Ihab El-Sayed Mosleh
- Fixed Prosthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah 22252, Saudi Arabia;
- Fixed Prosthodontics, Faculty of Dentistry, Cairo University, Cairo 11553, Egypt
| | - Elzahraa Eldwakhly
- Department of Clinical Dental Sciences, College of Dentistry, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
- Correspondence:
| |
Collapse
|
25
|
Yoon JM, Liu Y, Liu Y, Sun Y, Ye H, Zhou Y. The accuracy of a novel 3D digital evaluation method of intraoral fitness for removable partial dentures. Comput Biol Med 2022; 144:105348. [DOI: 10.1016/j.compbiomed.2022.105348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 11/27/2022]
|
26
|
Sánchez-Monescillo A, González-Serrano C, González-Serrano J, Malta Barbosa J, López-Suárez C, Duarte S. Effect of Luting Cement and Convergence Angle of the Preparation on the Internal Fit of Zirconia Restorations. MATERIALS 2021; 14:ma14247858. [PMID: 34947451 PMCID: PMC8708348 DOI: 10.3390/ma14247858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 11/28/2022]
Abstract
The objective was to evaluate the effect of luting agents and the preparation design on the internal fit of zirconia restorations. Sixty dies were prepared and divided in occlusal convergence angle of 6° (OC6) and 12° (OC12). CAD/CAM zirconia copings were fabricated (Lava All-Ceramic System). A zinc phosphate cement (ZPC); a glass ionomer cement (GIC); and a resin cement (RC) were studied. Specimens were sectioned and coping/die discrepancies were evaluated through Stereoscopic Microscopy. A closer fit was observed in OC12 when compared to OC6 (p < 0.001). For OC6 no significant differences were observed in between ZPC, GIC, and RC (p > 0.05). For OC12, a significantly closer fit was recorded on the ZPC subgroup when compared to the GIC subgroup (p < 0.001). Preparations of 12 degrees demonstrated a closer internal fit when compared to 6 degrees. Preparations of 12 degrees achieved better internal fit values with ZPC (Fortex) followed by RC (RelyX Unicem), and GIC (Ketac Cem). No differences were found when comparing different luting agents over 6° degrees preparations.
Collapse
Affiliation(s)
- Andrés Sánchez-Monescillo
- Norris Dental Science Center, Division of Restorative Sciences, Herman Ostrow School of Dentistry, University of Southern California, 925 W 34th St, DEN 311, Los Angeles, CA 90089, USA;
- Correspondence:
| | - Carlos González-Serrano
- IDIBO Research Group, Stomatology Department, School of Health Sciences, Rey Juan Carlos University, Av. de Atenas, S/N, Alcorcón, 28922 Madrid, Spain;
| | - José González-Serrano
- ORALMED Research Group, Department of Dental Clinical Specialities, School of Dentistry, Complutense University of Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain;
| | - João Malta Barbosa
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, 345 E 24th St, New York, NY 10010, USA;
| | - Carlos López-Suárez
- ICAPE Research Group, Department of Conservative Dentistry and Buccofacial Prosthesis, School of Dentistry, Complutense University of Madrid, Plaza Ramón y Cajal, s/n, 28040 Madrid, Spain;
| | - Sillas Duarte
- Norris Dental Science Center, Division of Restorative Sciences, Herman Ostrow School of Dentistry, University of Southern California, 925 W 34th St, DEN 311, Los Angeles, CA 90089, USA;
| |
Collapse
|
27
|
Freire Y, Gonzalo E, Lopez-Suarez C, Pelaez J, Suarez MJ. Evaluation of the marginal fit of monolithic crowns fabricated by direct and indirect digitization. J Prosthodont Res 2021; 65:291-297. [PMID: 33041277 DOI: 10.2186/jpr.jpr_d_20_00003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Purpose To evaluate the influence of intraoral and extraoral digitization systems on marginal discrepancy of monolithic lithium disilicate and monolithic zirconia computer-aided design-computer-aided manufacturing (CAD-CAM) crowns.Methods Forty standardized machined stainless steel specimens with the characteristics of a first molar were manufactured and randomly assigned to two groups (n=20 each), depending on their material: monolithic lithium disilicate ceramic (LM), and monolithic zirconia (ZM). Then, each group was subdivided into two depending on the scanning system used: intraoral scanner (IOS), and extraoral scanner (EOS). The digitization process was standardized with two methacrylate devices, one for each scanner. After scanning and manufacturing of the crowns, the marginal discrepancy was measured under a scanning electron microscope (SEM). Data analysis was made using two-way analysis of variance (ANOVA) and the effect size with Cohen's d.Results All the measurements were within the limits considered acceptable. Regardless the restorative material significant differences between scanners were observed, being the effect from low to moderate. However, no differences were observed between the scanners in either the lithium disilicate or zirconia group.Conclusions The intraoral scan showed lower marginal discrepancy than the extraoral scan in CAD-CAM monolithic crowns, but these differences were not observed in each of the ceramic systems.
Collapse
Affiliation(s)
- Yolanda Freire
- Department of Conservative Dentistry and Buccofacial Prostheses, University Complutense of Madrid, Madrid, Spain
| | - Esther Gonzalo
- Department of Conservative Dentistry and Buccofacial Prostheses, University Complutense of Madrid, Madrid, Spain
| | - Carlos Lopez-Suarez
- Department of Conservative Dentistry and Buccofacial Prostheses, University Complutense of Madrid, Madrid, Spain
| | - Jesus Pelaez
- Department of Conservative Dentistry and Buccofacial Prostheses, University Complutense of Madrid, Madrid, Spain
| | - Maria J Suarez
- Department of Conservative Dentistry and Buccofacial Prostheses, University Complutense of Madrid, Madrid, Spain
| |
Collapse
|
28
|
Chaturvedi S, Alqahtani NM, Addas MK, Alfarsi MA. Marginal and internal fit of provisional crowns fabricated using 3D printing technology. Technol Health Care 2021; 28:635-642. [PMID: 32280071 DOI: 10.3233/thc-191964] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Clinicians routinely provide provisional crowns following teeth preparation. Three-dimensional (3D) printing technology could be used over conventional methods for better fit as lack of adequate fit would result in plaque accumulation, micro-leakage, teeth sensitivity, caries and periodontal diseases. OBJECTIVE The aim of the study was to evaluate the marginal and internal fit of provisional crowns fabricated using 3D printing technology and to compare it with that of compression molding and milling methods. METHODS Ninety study models were fabricated by duplicating metal master models of the maxillary first premolar molar with three different finish line chamfer, rounded shoulder and rounded shoulder with bevel. On each study model, provisional crowns were fabricated using compression molding (Mo. group, n= 30 - by over impression technique), milling (Mi. group, n= 30 - by 5-axis dental milling machine), and 3D printing method (3D-P. group, n= 30 - by 3D printer). Marginal and internal fit of the samples were evaluated by measuring gap using a scanning electron microscope with a magnification of 27 ×, at 7 zones A-G on different finish line models. The data were statistically analysed using one-way analysis of variance (ANOVA) at the 0.05 significance level. The p-values were calculated using Dunnett's test. RESULTS The marginal gap was minimal for the 3D-P. group for each finish line with lowest for rounded shoulder with bevel at zone A 30.6 ± 5.3 and at zone G 32.8 ± 5.4. In axial area, i.e. zones B and F, the minimum gap was noticed for the Mo. group and in Occlusal area (cusp and fossa), for zones C-E maximum gap was determined in Mi. group followed by Mo. and 3D-P. groups. CONCLUSIONS 3D printed provisional crowns have better marginal and internal fit compared to milled and molded provisional crowns.
Collapse
|
29
|
Kayikci O, Ates SM. Comparison of marginal and internal fit of three-unit implant-supported fixed prosthetic substructures fabricated using CAD/CAM systems. Clin Oral Investig 2021; 26:1283-1291. [PMID: 34331593 DOI: 10.1007/s00784-021-04102-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/23/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVE This study compared the marginal and internal fit of implant-supported fixed dentures fabricated using CAD/CAM systems. MATERIALS AND METHODS A lower jaw model representing partial edentulism was produced. Two dental implants were inserted in the area of teeth 35 and 37, onto which cemented abutments were screwed. The model was scanned using a laboratory scanner and transferred to a design software program for substructure fabrication. Sixty substructures were fabricated out of each group for six substructure types (n = 10), cast Co-Cr (control), milling Co-Cr, laser sintering Co-Cr, titanium (Ti), zirconium, and polyetheretherketone (PEEK) substructures. The marginal and internal fit was evaluated using a silicone replica viewed under a stereomicroscope. The data were analyzed using the statistical package program for social sciences (SPSS, Chicago, IL, USA, v. 17) at a significance level of 0.05. Marginal and internal gaps were compared using the one-way ANOVA test and Tukey's post hoc test. The differences between abutment teeth were determined using the independent sample t-test. RESULTS There was a significant difference in the marginal gap between PEEK and Ti groups (p < 0.05) but no difference between other groups (p > 0.05). There was a significant difference in the internal gap between PEEK, laser sintering Co-Cr, and milling Co-Cr groups (p < 0.05) but no difference between other groups (p > 0.05). The PEEK group had a higher marginal gap than the Ti group and a higher internal gap than the DMLS Co-Cr group (p < 0.05). CONCLUSION All substructures have a marginal and internal fit within acceptable clinical limits. CLINICAL RELEVANCE This in vitro study suggests that materials and techniques used in CAD/CAM systems improve the fitting accuracy of implant-supported fixed restorations.
Collapse
Affiliation(s)
- Ozlem Kayikci
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey
| | - Sabit Melih Ates
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey.
| |
Collapse
|
30
|
Hassan LA, Goo CL. Effect of cement space on marginal discrepancy and retention of CAD/CAM crown. Dent Mater J 2021; 40:1189-1195. [PMID: 34078778 DOI: 10.4012/dmj.2020-408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This research aimed to evaluate the effect of cement space on the marginal discrepancy and retention of computer-aided design/computer-aided manufacturing (CAD/CAM) crowns. A total of 30 premolar Frasaco teeth were machined to receive crowns with cement spaces of 70, 90, and 110 μm. The marginal discrepancy measurements were done before and after cementation. Pull-off test was conducted using universal testing machine (UTM). Data was analyzed using two-way mixed ANOVA with post-hoc Bonferroni test and Kruskal-Wallis test. The crowns with cement space of 70 μm showed a significantly higher absolute marginal discrepancy than those with 90 and 110 μm. No significant effect on the crown retention was found. Within the limitations of this study, modifying cement space to 90 μm and 110 μm may improve the marginal adaptation of CAD/CAM crown, whereas adjusting cement space from 70 to 110 μm did not significantly affect the crown retention.
Collapse
Affiliation(s)
- Laila Azwa Hassan
- Department of Restorative Dentistry, Faculty of Dentistry, The National University of Malaysia
| | - Chui Ling Goo
- Department of Restorative Dentistry, Faculty of Dentistry, The National University of Malaysia
| |
Collapse
|
31
|
Effect of virtual cement gap settings on the marginal fit of cemented resin-ceramic crowns on implant abutments. J Prosthet Dent 2021; 125:804.e1-804.e6. [PMID: 33934821 DOI: 10.1016/j.prosdent.2021.02.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/22/2021] [Accepted: 02/23/2021] [Indexed: 11/23/2022]
Abstract
STATEMENT OF PROBLEM Agreement on the perfect virtual cement space value for computer-aided design and computer-aided manufacturing (CAD-CAM) implant-supported resin-ceramic crowns with the best marginal adaptation is lacking. The range of cement gap settings in some CAD design software programs is wide (0 to 200 μm), and manufacturer recommendations regarding the best cement gap setting for certain types of ceramics is not specific. PURPOSE The purpose of this in vitro study was to evaluate the effect of virtual cement gap settings on the marginal fit of cemented resin-ceramic crowns on implant abutments. MATERIAL AND METHODS Thirty implant analogs and matching stock abutments were coupled and implanted into autopolymerizing acrylic resin blocks. Three groups (n=10) of resin-ceramic molar crowns with 3 different virtual cement space settings (40, 60, and 100 μm) were designed by using a CAD design software program. The crowns were cemented over their corresponding abutments under a static load by using a specially designed cementing device. A scanning electron microscope was used to measure the mean vertical marginal gap (MG) for each group, where a total of 120 measurements for each of the 3 groups (12 sites per crown and 10 crowns per group) were evaluated. One-way analysis of variance and the post hoc Tukey pairwise comparison tests were used to analyze the data (α=.05). RESULTS A significant difference (P<.001) was found between the MG values of the resin-ceramic implant-supported crowns fabricated by using the 3 cement space settings. The smallest MG was obtained with the 60-μm setting as compared with the 40-μm and 100-μm settings. CONCLUSIONS A limited inverse relation was found between the MGs of CAD-CAM-fabricated resin-ceramic implant-supported crowns and the cement gap settings in the exocad software program. The smallest MGs were obtained when a 60-μm cement space value was used (P<.001).
Collapse
|
32
|
Molinero-Mourelle P, Cascos-Sanchez R, Yilmaz B, Lam WYH, Pow EHN, Del Río Highsmith J, Gómez-Polo M. Effect of Fabrication Technique on the Microgap of CAD/CAM Cobalt-Chrome and Zirconia Abutments on a Conical Connection Implant: An In Vitro Study. MATERIALS 2021; 14:ma14092348. [PMID: 33946477 PMCID: PMC8125438 DOI: 10.3390/ma14092348] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/20/2021] [Accepted: 04/27/2021] [Indexed: 01/03/2023]
Abstract
The aim of this in vitro study was to investigate the microgaps at the implant-abutment interface when zirconia (Zr) and CAD/CAM or cast Co-Cr abutments were used. METHODS Sixty-four conical connection implants and their abutments were divided into four groups (Co-Cr (milled, laser-sintered and castable) and Zirconia (milled)). After chewing simulation (300,000 cycles, under 200 N loads at 2 Hz at a 30° angle) and thermocycling (10,000 cycles, 5 to 50 °C, dwelling time 55 s), the implant-abutment microgap was measured 14 times at each of the four anatomical aspects on each specimen by using a scanning electron microscope (SEM). Kruskal-Wallis and pair-wise comparison were used to analyze the data (α = 0.05). RESULTS The SEM analysis revealed smaller microgaps with Co-Cr milled abutments (0.69-8.39 μm) followed by Zr abutments (0.12-6.57 μm), Co-Cr sintered (7.31-25.7 μm) and cast Co-Cr (1.68-85.97 μm). Statistically significant differences were found between milled and cast Co-Cr, milled and laser-sintered Co-Cr, and between Zr and cast and laser-sintered Co-Cr (p < 0.05). CONCLUSIONS The material and the abutment fabrication technique affected the implant-abutment microgap magnitude. The Zr and the milled Co-Cr presented smaller microgaps. Although the CAD/CAM abutments presented the most favorable values, all tested groups had microgaps within a range of 10 to 150 μm.
Collapse
Affiliation(s)
- Pedro Molinero-Mourelle
- Department of Conservative Dentistry and Orofacial Prosthodontics, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain; (R.C.-S.); (J.D.R.H.); (M.G.-P.)
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, 3007 Bern, Switzerland;
- Correspondence: ; Tel.: +34-913941922
| | - Rocio Cascos-Sanchez
- Department of Conservative Dentistry and Orofacial Prosthodontics, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain; (R.C.-S.); (J.D.R.H.); (M.G.-P.)
| | - Burak Yilmaz
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, 3007 Bern, Switzerland;
- Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, 3007 Bern, Switzerland
| | - Walter Yu Hang Lam
- Prosthodontics, Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, Sai Ying Pun, Hong Kong, China; (W.Y.H.L.); (E.H.N.P.)
| | - Edmond Ho Nang Pow
- Prosthodontics, Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, Sai Ying Pun, Hong Kong, China; (W.Y.H.L.); (E.H.N.P.)
| | - Jaime Del Río Highsmith
- Department of Conservative Dentistry and Orofacial Prosthodontics, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain; (R.C.-S.); (J.D.R.H.); (M.G.-P.)
| | - Miguel Gómez-Polo
- Department of Conservative Dentistry and Orofacial Prosthodontics, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain; (R.C.-S.); (J.D.R.H.); (M.G.-P.)
| |
Collapse
|
33
|
Sharma A, Abraham D, Gupita A, Singh A, Sharma N. Comparative Evaluation of the Marginal Fit of Inlays Fabricated by Conventional and Digital Impression Techniques: A Stereomicroscopic Study. Contemp Clin Dent 2021; 11:237-244. [PMID: 33776349 PMCID: PMC7989749 DOI: 10.4103/ccd.ccd_375_19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 05/17/2020] [Accepted: 06/08/2020] [Indexed: 11/04/2022] Open
Abstract
Context Marginal fit being the prime concern of indirect restorations. Inlays can be either fabricated by conventional technique or computer-aided design and computer-aided manufacturing (CAD/CAM) techniques. CAD/CAM is the most evolving digital technique with faster, quicker, and precise results. Aims The aim of this study is to evaluate and compare the marginal fit of MOD inlays fabricated with two different CAD/CAM methods and conventional fabrication methods. Settings and Design Mesio-occlusal-distal preparation was done on a maxillary premolar typhodont tooth and divided into the following groups. Group A: 30 inlays were fabricated through the conventional impression technique. Group B: Preparation was scanning using an intraoral scanner followed by subtractive milling (Group B1) and subtractive milling of wax patterns (Group B2). Similarly, subgrouping was carried out for Group C except that an extraoral scanner was used. Occlusal and the cervical marginal fit were assessed using the replica technique and stereomicroscope. One-way ANOVA followed by Tukey honestly significant difference post hoc test for determining differences at a 95% level of confidence (P = 0.05). Results Group A had the highest marginal discrepancy in comparison to Group B and Group C at occlusal and cervical edges, whereas subtractive milling showed comparatively better results than subtractive milling of wax patterns at cervical edges and similar results at occlusal edges. Conclusions Ceramic inlays fabricated by subtractive milling yielded better results.
Collapse
Affiliation(s)
- Anamika Sharma
- Department of Conservative Dentistry and Endodontics, Manav Rachna Dental College, Faridabad, Haryana, India
| | - Dax Abraham
- Department of Conservative Dentistry and Endodontics, Manav Rachna Dental College, Faridabad, Haryana, India
| | - Alpa Gupita
- Department of Conservative Dentistry and Endodontics, Manav Rachna Dental College, Faridabad, Haryana, India
| | - Arundeep Singh
- Department of Conservative Dentistry and Endodontics, Manav Rachna Dental College, Faridabad, Haryana, India
| | - Naresh Sharma
- Department of Pedodontics and Preventive Dentistry, Manav Rachna Dental College, Faridabad, Haryana, India
| |
Collapse
|
34
|
Ogunc A, Yildirim Avcu G. Effect of repeated firings on the marginal and internal adaptation of implant-supported metal-ceramic restorations fabricated with different thicknesses and fabrication methods. J Prosthet Dent 2021; 125:504.e1-504.e6. [DOI: 10.1016/j.prosdent.2020.10.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 11/16/2022]
|
35
|
尹 祯, 王 子, 陈 俊, 孙 玉, 刘 云, 叶 红, 周 永. [Evaluation of methods for fitness of removable partial denture]. BEIJING DA XUE XUE BAO. YI XUE BAN = JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2021; 53:406-412. [PMID: 33879919 PMCID: PMC8072425 DOI: 10.19723/j.issn.1671-167x.2021.02.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Indexed: 06/12/2023]
Abstract
OBJECTIVE To compare the differences and indications of three evaluation methods for fitness evaluation of removable partial denture (RPD). METHODS A RPD was fabricated and seated on the stone cast of a partially edentulous mandible, and the spaces between RPD and stone cast were recorded with polyvinyl siloxane (PVS) impression material forming PVS replicas. Using cross sectional measurement, the average thicknesses of PVS replicas were measured under stereomicroscope with different numbers of selected measuring points in the denture base, major connector, occlusal rest of the RPD, and the average thicknesses of the PVS replicas measured with different numbers of measuring points were compared using one-way analysis of variance (ANOVA) and independent sample t test. Three kinds of method, including cross sectional measurement, three-dimensional analysis on the stone cast, and three-dimensional analysis on the polyether cast, were applied to measure the average thicknesses of the PVS replicas, and the average thicknesses of the PVS replicas measured by these three evaluation methods were compared with ANOVA. RESULTS For cross sectional measurement, statistically significant differences were found in the average thicknesses of the PVS replicas in the denture base and the major connector among the different numbers of measuring points (P < 0.05), but no differences were found in the average thicknesses of the PVS replicas in the occlusal rest (P>0.05). There were significant differences among the average thicknesses of the PVS replicas measured by these three evaluation methods in each component of the RPD (P < 0.01). The average thickness measured by three-dimensional analysis on the stone cast and three-dimensional analysis on polyether cast were smaller than that measured by cross sectional measurement (P < 0.05). And there were no differences between the average thicknesses of PVS replicas measured by three-dimensional analysis on stone cast and three-dimensional analysis on polyether cast (P>0.05). CONCLUSION For cross sectional measurement, the average thickness of the PVS replicas was influenced by the number of measuring points, and the measurement accuracy of cross sectional measurement was not reliable enough. Three-dimensional analysis on stone cast which is suitable for evaluation in vitro and three-dimensional analysis on polyether cast which is suitable for evaluation in vivo can evaluate the fitness of RPD more comprehensively and effectively than that of cross sectional measurement.
Collapse
Affiliation(s)
- 祯敏 尹
- 北京大学口腔医学院·口腔医院,修复科 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 子轩 王
- 北京大学口腔医学院·口腔医院,修复科 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 俊锴 陈
- 北京大学口腔医学院·口腔医院,修复科 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 玉春 孙
- 北京大学口腔医学院·口腔医院,口腔医学数字化研究中心 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Center for Digital Dentistry, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 云松 刘
- 北京大学口腔医学院·口腔医院,修复科 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 红强 叶
- 北京大学口腔医学院·口腔医院,修复科 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 永胜 周
- 北京大学口腔医学院·口腔医院,修复科 国家口腔疾病临床医学研究中心 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室,北京 100081Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| |
Collapse
|
36
|
Topkara C, Keleş A. Examining the adaptation of modified endocrowns prepared with CAD-CAM in maxillary and mandibular molars: A microcomputed tomography study. J Prosthet Dent 2021; 127:744-749. [PMID: 33454117 DOI: 10.1016/j.prosdent.2020.12.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 11/27/2020] [Accepted: 12/01/2020] [Indexed: 10/22/2022]
Abstract
STATEMENT OF PROBLEM Endocrowns have been reported to be successful restorations for endodontically treated molars. However, comparisons between maxillary and mandibular molars, with different pulp chamber configurations are lacking. Information on the influence of venting on the adaptation of endocrowns is also lacking. PURPOSE The purpose of this in vitro study was to evaluate the adaptation of endocrowns in maxillary and mandibular molars by means of microcomputed tomography (μCT). MATERIAL AND METHODS Mandibular and maxillary first molars were divided into 4 groups (n=10): ManE: mandibular endocrown; ModManE: modified mandibular endocrown; MaxE: maxillary endocrown; and ModMaxE: modified maxillary endocrown. Endocrowns were produced by using computer-aided design and computer-aided manufacture (CAD-CAM). Modification was carried out on the part of the endocrown that extended into the pulp chamber by preparing vents. The specimens were cemented and scanned by using μCT, the images reconstructed, and the internal and marginal adaptation examined. Statistical analyses were performed by using a 3-way ANOVA, 2-way ANOVA, and the independent samples t test (α=.05). RESULTS ManE displayed better mean ±standard deviation internal adaptation (182 ±59 μm) than MaxE (215 ±55 μm) (P<.01). Regardless of the groups, the pulpal floor was the area with the poorest fit (P<.001). The marginal gap of mandibular molars (91 ±20 μm) was lower than that of maxillary molars (110 ±26 μm) (P<.05). The effect of modifying endocrowns on the marginal gap was not found to be statistically significant (P>.05). CONCLUSIONS Internal and marginal adaptation of endocrowns differ between maxillary and mandibular molars.
Collapse
Affiliation(s)
- Can Topkara
- Research Assistant, Department of Endodontics, Faculty of Dentistry, Ondokuz Mayıs University, Samsun, Turkey
| | - Ali Keleş
- Associate Professor, Department of Endodontics, Faculty of Dentistry, Ondokuz Mayıs University, Samsun, Turkey.
| |
Collapse
|
37
|
Licurci CAA, Lins L, Garbossa M, Canabarro A. A comparative study between replica and cementation techniques in the evaluation of internal and marginal misfits of single crowns. J Prosthet Dent 2020; 127:609-616. [PMID: 33342611 DOI: 10.1016/j.prosdent.2020.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 10/30/2020] [Accepted: 11/02/2020] [Indexed: 11/26/2022]
Abstract
STATEMENT OF PROBLEM Systematic reviews about the internal and marginal misfits of fixed prostheses have identified a limited number of clinical studies, suggesting the need for further research on the subject. Although the replica technique has been described as suitable for this purpose, few studies have validated it. PURPOSE The purpose of this in vitro study was to compare the ability of a nondestructive replica technique and a destructive cementation technique to assess internal and marginal misfits of zirconia copings, considering current materials and designs. MATERIAL AND METHODS Twelve anatomic prefabricated abutments (Neodent) were used to manufacture zirconia copings following the Ceramill (Amann Girrbach AG) (n=6) and Lava (3M ESPE) (n=6) systems. Replications of the cementation line were obtained with polyvinyl siloxane for the replica technique, and the copings were then cemented and sectioned to obtain 5 surfaces (buccal, palatal, mesial, distal, and incisal) and the linear and angle regions (internal axiogingival and axioincisal angles). The thickness of the cement line and silicone film was measured at 45 reference points on each abutment. A total of 540 measurements were made with an optical microscope with a digital camera at magnifications of ×100 and ×200. Data were analyzed by repeated-measures ANOVA and the Bonferroni multiple comparison tests (α=.05). RESULTS In the internal misfit evaluation, the mean values observed for the cementation technique and replica technique were as follows: angle regions, 70.6 μm and 72.2 μm; linear regions, 59.1 μm and 59.6 μm; incisal surface, 139.0 μm and 139.8 μm; buccal surface, 72.4 μm and 73.8 μm; palatal surface, 73.1 μm and 75.2 μm; mesial surface, 74.1 μm and 73.8 μm; distal surface, 75.0 μm and 76.3 μm; and overall mean, 73.6 μm and 74.8 μm, respectively. In the evaluation of the marginal misfit, the mean values found were: buccal surface, 36.7 μm and 37.8 μm; palatal surface, 37.5 μm and 36.8 μm; mesial surface, 44.0 μm and 43.7 μm; and distal surface, 44.6 μm and 45.2 μm, respectively. No significant differences were found between the 2 techniques for all locations and systems (P>.05). CONCLUSIONS Within the limitations of this in vitro study, both techniques presented the same ability to assess the internal and marginal misfits when the location and overall mean averages were evaluated (P>.05).
Collapse
Affiliation(s)
- Cristiana A A Licurci
- Postgraduate student, Department of Oral Rehabilitation, Veiga de Almeida University (UVA), Rio de Janeiro, Brazil
| | - Leonardo Lins
- PhD student, Department of Oral Rehabilitation, Veiga de Almeida University (UVA), Rio de Janeiro, Brazil
| | - Marcelo Garbossa
- Professor, Department of Prosthodontics, Veiga de Almeida University (UVA), Rio de Janeiro, Brazil
| | - Antonio Canabarro
- Full Professor, Department of Oral Rehabilitation, Veiga de Almeida University (UVA), Rio de Janeiro, Brazil; Associate Professor, Department of Periodontology, State University of Rio de Janeiro (UERJ), Rio de Janeiro, Brazil.
| |
Collapse
|
38
|
Daou EE. X-ray microtomographic evaluation of the absolute marginal fit of fixed prostheses made from soft Co-Cr and zirconia. J Prosthet Dent 2020; 127:289-294. [PMID: 33279157 DOI: 10.1016/j.prosdent.2020.07.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/23/2020] [Accepted: 07/23/2020] [Indexed: 11/30/2022]
Abstract
STATEMENT OF PROBLEM The absolute marginal fit of CAD-CAM presintered fixed partial dentures has been poorly documented. PURPOSE The purpose of this in vitro study was to evaluate the marginal fit of presintered cobalt-chromium (Co-Cr) and zirconia 3-unit fixed partial dentures by using X-ray microcomputed tomography (μCT). MATERIAL AND METHODS A metal model was prepared from a typodont to receive fixed partial dentures (N=12). The maxillary first premolar and first molar were prepared with a circumferential 1.2-mm chamfer and 2-mm occlusal reduction. The dies were scanned and assigned to 1 of 2 groups to receive the prostheses made of presintered Co-Cr or presintered zirconia (n=6). Each framework was seated on its model without load application. The abutments were scanned by using μCT. A circle with 10 diameters, with a step of 18 degrees, was projected at the center of the obtained image. Absolute marginal discrepancy and marginal gap mean values were measured, and overextended and underextended margins determined. The data were analyzed by using the Levene t test and ANOVA (α=.05). RESULTS No statistically significant difference was found in the marginal fit between the materials tested (P=.939). The mean values were 66 ±14 μm for Co-Cr and 61 ±12 μm for zirconia. The absolute marginal discrepancy mean value for the premolar was 69 ±12 μm and 41 ±9 μm for the molar (P<.001). Overextension was predominant for both materials tested, with a higher percentage reported for the zirconia group. CONCLUSIONS Presintered alloys presented clinically acceptable adaptation with a predominance of marginal overextensions.
Collapse
Affiliation(s)
- Elie E Daou
- Lecturer, Department of Prosthodontics Faculty of Dentistry, Faculty of Dental Medicine, Beirut, Lebanon.
| |
Collapse
|
39
|
Internal and marginal discrepancies associated with stereolithography (SLA) additively manufactured zirconia crowns. J Prosthet Dent 2020; 124:730-737. [DOI: 10.1016/j.prosdent.2019.09.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 09/25/2019] [Accepted: 09/25/2019] [Indexed: 11/17/2022]
|
40
|
Salerno M, Vizza F, Amaroli A, Signore A, Itri A. 3D optical profilometer analysis of the marginal gap of Class II restorations made with different materials for vital pulp therapy procedures. Dent Mater J 2020; 40:407-415. [PMID: 33208576 DOI: 10.4012/dmj.2020-066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We considered Class II dental cavities in critical tooth areas concerned with vital pulp therapy, and evaluated the marginal gap after treatment with Biodentine and Geristore, and one composite after either etching and adhesive (V2) and after use of a self-etching system (iBond Universal). We measured the surface morphology at the marginal gap by optical profilometry, and carried out analysis of the 3D data according to a new effective definition of marginal gap. The defined quantity was assessed for statistical significance of the apparent differences. The largest gaps appeared for Geristore (first) and Biodentine (not significantly lower), whereas the gaps of the composite controls were both lower, the lowest being the two-step self-etched system with respect to the three-steps etched and adhesive system, yet without statistical significance. Obviously, there is still room for improvement of the vital pulp therapy restorative materials, as compared to the use of standard composite systems.
Collapse
Affiliation(s)
- Marco Salerno
- Istituto Italiano di Tecnologia, Materials Characterization Facility.,Ronin Institute
| | - Francesca Vizza
- Department of Therapeutic Dentistry, I. M. Sechenov First Moscow State Medical University
| | - Andrea Amaroli
- Department of Orthopaedic Dentistry, I. M. Sechenov First Moscow State Medical University.,Department of Surgical Sciences and Integrated Diagnostic, University of Genoa
| | - Antonio Signore
- Department of Therapeutic Dentistry, I. M. Sechenov First Moscow State Medical University
| | - Angelo Itri
- Department of Therapeutic Dentistry, I. M. Sechenov First Moscow State Medical University
| |
Collapse
|
41
|
Gonzalo E, Vizoso B, Lopez-Suarez C, Diaz P, Pelaez J, Suarez MJ. Evaluation of Milled Titanium versus Laser Sintered Co-Cr Abutments on the Marginal Misfit in Internal Implant-Abutment Connection. MATERIALS 2020; 13:ma13214873. [PMID: 33143092 PMCID: PMC7663543 DOI: 10.3390/ma13214873] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/20/2020] [Accepted: 10/26/2020] [Indexed: 11/28/2022]
Abstract
The precision of fit at the implant-abutment connection is an important criterion for the clinical success of restorations and implants. Several factors are involved among which are the abutment materials and manufacturing techniques. The aim of this study was to investigate the effect of two materials and methods of manufacturing implant abutments, milled titanium versus laser sintered Co-Cr, on the marginal misfit at the implant-abutment interface. Scanning electron microscopes (SEM) were used to geometrically measure the marginal vertical discrepancy of a total of 80 specimens, classified into eight categories, according to the implant system and abutment. The data were statistically analyzed by Student’s paired t test, one-way and two-way ANOVA with the Bonferroni-Holm correction at the significance level of p = 0.05. Milled titanium abutments demonstrated the lowest misfit values in the implant systems analyzed. The marginal fit of all the groups was within the clinically acceptable range for implant prostheses.
Collapse
|
42
|
Ahmed WM, Shariati B, Gazzaz AZ, Sayed ME, Carvalho RM. Fit of tooth-supported zirconia single crowns-A systematic review of the literature. Clin Exp Dent Res 2020; 6:700-716. [PMID: 32885613 PMCID: PMC7745068 DOI: 10.1002/cre2.323] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 07/07/2020] [Accepted: 07/22/2020] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The purpose of this study is to systematically map all the factors that influence the fit and adaptation of zirconia crowns and/or copings. MATERIALS AND METHODS The investigational strategy involved carrying out an electronic search between December 1, 2009 and September 1, 2019 through the Embase and Medline databases using Boolean operators to locate appropriate articles. RESULTS A total of 637 articles were discovered after the removal of duplicates, and 46 of these were selected for evaluation. Further, a quality assessment was performed using GRADE evaluation criteria. CONCLUSIONS Shoulder finish line preparations had slightly better marginal fit compared to chamfer finish lines. Crowns obtained from digital impressions had comparable to superior marginal adaptation compared to conventional impressions. Increasing cement space showed to improve zirconia crown adaptation. Cementation and veneering zirconia frameworks found to increase the marginal and internal gaps. Limited information is available on the effect of the alteration of sintering time/Temperature and/or sintering techniques on the adaptation of zirconia crowns. Most of the selected studies had a moderate quality assessment evaluation. Future studies could investigate the chair-side, ultra-fast sintering effect on the marginal gap of zirconia crowns.
Collapse
Affiliation(s)
- Walaa Magdy Ahmed
- Faculty of Dentistry, The University of British Columbia, Vancouver, British Columbia, Canada.,Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Batoul Shariati
- Faculty of Dentistry, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Arwa Z Gazzaz
- Faculty of Dentistry, The University of British Columbia, Vancouver, British Columbia, Canada.,College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | | | - Ricardo M Carvalho
- Faculty of Dentistry, The University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
43
|
Falahchai M, Babaee Hemmati Y, Neshandar Asli H, Neshandar Asli M. Marginal adaptation of zirconia‐reinforced lithium silicate overlays with different preparation designs. J ESTHET RESTOR DENT 2020; 32:823-830. [DOI: 10.1111/jerd.12642] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/21/2020] [Accepted: 07/30/2020] [Indexed: 12/01/2022]
Affiliation(s)
- Mehran Falahchai
- Dental Sciences Research Center, Department of Prosthodontics School of Dentistry, Guilan University of Medical Sciences Rasht Iran
| | - Yasamin Babaee Hemmati
- Dental Sciences Research Center, Department of Orthodontics School of Dentistry, Guilan University of Medical Sciences Rasht Iran
| | - Hamid Neshandar Asli
- Dental Sciences Research Center, Department of Prosthodontics School of Dentistry, Guilan University of Medical Sciences Rasht Iran
| | - Marzieh Neshandar Asli
- Undergraduate student, Dental School Anzali Campus, Guilan University of Medical Sciences Rasht Iran
| |
Collapse
|
44
|
Raposo LH, Borella PS, Ferraz DC, Pereira LM, Prudente MS, Santos-Filho PC. Influence of Computer-aided Design/Computer-aided Manufacturing Diamond Bur Wear on Marginal Misfit of Two Lithium Disilicate Ceramic Systems. Oper Dent 2020; 45:416-425. [PMID: 31860389 DOI: 10.2341/19-089-l] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2019] [Indexed: 11/23/2022]
Abstract
CLINICAL RELEVANCE Marginal misfit of monolithic lithium disilicate ceramic crowns obtained from a chairside computer-aided design/computer-aided manufacturing system is affected after successive millings using a single diamond bur set. This fact can be critical for the longevity of indirect restorations. SUMMARY
Collapse
|
45
|
Ferrairo BM, Piras FF, Lima FF, Honório HM, Duarte MAH, Borges AFS, Rubo JH. Comparison of marginal adaptation and internal fit of monolithic lithium disilicate crowns produced by 4 different CAD/CAM systems. Clin Oral Investig 2020; 25:2029-2036. [PMID: 32783095 DOI: 10.1007/s00784-020-03511-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/06/2020] [Indexed: 12/01/2022]
Abstract
OBJECTIVES To evaluate the marginal adaptation and internal space of crowns produced by 4 CAD/CAM systems using microcomputed tomography (μCT) and replica technique (RT). MATERIALS AND METHODS Monolithic lithium disilicate crowns were milled (Ceramill, Cerec, EDG, and Zirkonzahn) (n = 10). The cement film obtained with low viscosity silicone was scanned by the μCT system and captured by a stereomicroscope, according to RT. Two-way ANOVA followed by Tukey's test were used for statistical analysis (α = 0.05). A uniformity index (UI) was idealized to describe the distribution of crowns' internal space and submitted to the Kruskal-Wallis and Tukey's test (α = 0.05). The correlation between μCT and RT was performed by Pearson's Correlation Coeficient (α = 0.05). RESULTS Marginal adaptation and internal space were statistically significant different between the experimental groups for the μCT and RT (p < 0.05). The medians of the 4 systems tested were within clinically acceptable range and the mean (± SD) highest marginal discrepancy was recorded in the Ceramill group at 133.0 ± 71.5 μm (μCT) and 90.6 ± 38.5 μm (RT). For internal fit, the UI disclosed a better distribution of the internal space for the Zirkonzahn group (p < 0.001). There was a strong correlation between the methods (p = 0.01 and r = 0.69). CLINICAL RELEVANCE Because of the variability of the CAD/CAM systems available, evaluating their accuracy is of clinical interest. The 4 systems are capable to produce restorations adaptated within clinically appropriate levels. The μCT and RT are efficient adaptation methodologies.
Collapse
Affiliation(s)
- Brunna Mota Ferrairo
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil.
| | - Fernanda Furtado Piras
- Department of Prosthodontics and Periodontology, Faculty of Dentistry, University of Marília (UNIMAR), Avenida Higino Muzi Filho, 1001, Marília, SP, 17525-902, Brazil
| | - Feranda Ferruzzi Lima
- Department of Dentistry, Maringá State University, Maringá, PR, Brazil.,Department of Restorative Dentistry and Prosthodontics, Ingá University Center - UNINGÁ, School of Dentistry, Maringá, PR, Brazil
| | - Heitor Marques Honório
- Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil
| | - Marco Antonio Hungaro Duarte
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil
| | - Ana Flávia Sanches Borges
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil
| | - José Henrique Rubo
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil
| |
Collapse
|
46
|
Effect of different fabrication techniques on the marginal precision of polyetheretherketone single-crown copings. J Prosthet Dent 2020; 124:565.e1-565.e7. [PMID: 32636071 DOI: 10.1016/j.prosdent.2020.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/10/2020] [Accepted: 04/10/2020] [Indexed: 11/20/2022]
Abstract
STATEMENT OF PROBLEM Demand is increasing for polyetheretherketone (PEEK) as a fixed dental prosthesis core material. However, information is lacking about how the precision of these restorations is affected by the fabrication procedures. PURPOSE The purpose of this in vitro study was to evaluate the influence of different fabrication techniques on the marginal precision of PEEK single-crown copings. MATERIAL AND METHODS A stainless-steel master die was designed to simulate a prepared mandibular second molar to receive ceramic crowns. Thirty PEEK copings were fabricated and divided into 3 groups (n=10) according to the fabrication technique: milled from a prefabricated PEEK blank by using a computer-aided design and computer-aided manufacturing (CAD-CAM) system (PC); pressed from prefabricated PEEK pellets (PP); and pressed from PEEK granules (PG); in addition, 3-mol yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) copings (n=10) were produced by using the same CAD-CAM system and served as a control. Marginal precision measurements (in μm) were recorded at 4 reference points on each coping by using a digital microscope. The data obtained were statistically analyzed by using 1-way ANOVA and the pair-wise Tukey (HSD) test to study the difference between group mean values (α=.05). RESULTS The overall mean ±standard deviation marginal gap at the marginal opening for the copings was 78 ±10 μm for PEEK granules copings, 72 ±9 μm for PEEK pellet copings, 45 ±6 μm for PEEK CAD-CAM copings, and 43 ±1 μm for the 3Y-TZP CAD-CAM control. A statistically significant difference was found between the milled and pressed copings as indicated by the ANOVA test (P<.001). The pair-wise Tukey honestly significant difference (HSD) test showed a nonsignificant difference (P>.05) between milled 3Y-TZP and milled PEEK copings; moreover, no significant difference was observed between the PEEK copings pressed from pellets or granules (P>.05). CONCLUSIONS The marginal precision of PEEK CAD-CAM-fabricated copings showed significantly lower mean marginal gap values than PEEK pressed copings. The marginal gap mean values recorded were all within a clinically acceptable range (120 μm).
Collapse
|
47
|
Vág J, Nagy Z, Bocklet C, Kiss T, Nagy Á, Simon B, Mikolicz Á, Renne W. Marginal and internal fit of full ceramic crowns milled using CADCAM systems on cadaver full arch scans. BMC Oral Health 2020; 20:189. [PMID: 32631333 PMCID: PMC7339429 DOI: 10.1186/s12903-020-01181-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/29/2020] [Indexed: 11/25/2022] Open
Abstract
Background Chairside systems are becoming more popular for fabricating full-ceramic single restorations, but there is very little knowledge about the effect of the entire workflow process on restoration fit. Therefore, this study aimed to compare the absolute marginal discrepancy (AMD) and the full internal fit (FULL) of all-ceramic crowns made by two chairside systems, Planmeca FIT and CEREC, with detailed and standard mill settings. Methods One upper molar was prepared for an all-ceramic crown in human cadaver maxilla. Full-arch scans were made by Emerald or Omnicam four times each. Twenty-four e.max crowns were designed and milled by the Planmill 30s or 40s or CEREC MCXL mills with either detailed or standard settings. The cadaver tooth was extracted, and each crown was fixed on it and scanned by a high-resolution microCT scanner. The AMD and FULL were measured digitally in mesio-distal and bucco-lingual 2D slices. The actual and predicted times of the milling were also registered. Results No differences were observed between detailed or standard settings in either system. The AMD was significantly higher with CEREC (132 ± 12 μm) than with either Planmill 30s (71 ± 6.9 μm) or 40s (78 ± 7.7 μm). In standard mode, the FULL was significantly higher with CEREC (224 ± 9.6 μm) than with either Planmill 30s (169 ± 8.1 μm) or 40s (178 ± 8.5 μm). There was no difference between actual and predicted time with the two Planmeca models, but with CEREC, the actual time was significantly higher than the predicted time. The 30s had significantly higher actual and predicted times compared to all other models. Across all models, the average milling time was 7.2 min less in standard mode than in detailed mode. Conclusions All fit parameters were in an acceptable range. No differences in fit between Planmeca models suggest no effect of spindle number on accuracy. The detailed setting has no improvement in the marginal or internal fit of the restoration, yet it increases milling time.
Collapse
Affiliation(s)
- János Vág
- Department of Conservative Dentistry, Semmelweis University, Szentkirályi utca 47, Budapest, H-1088, Hungary.
| | - Zsolt Nagy
- Department of Conservative Dentistry, Semmelweis University, Szentkirályi utca 47, Budapest, H-1088, Hungary
| | - Christopher Bocklet
- College of Dental Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Tamás Kiss
- János Szentágothai Research Centre & Department of Pharmacology and Pharmacotherapy, Medical School, University of Pecs, Ifjúság útja 20, Pécs, H-7624, Hungary
| | - Ákos Nagy
- Department of Dentistry, Oral and Maxillofacial Surgery, University of Pecs, Pecs, Hungary
| | - Botond Simon
- Department of Conservative Dentistry, Semmelweis University, Szentkirályi utca 47, Budapest, H-1088, Hungary
| | - Ákos Mikolicz
- Department of Conservative Dentistry, Semmelweis University, Szentkirályi utca 47, Budapest, H-1088, Hungary
| | - Walter Renne
- Department of Oral Rehabilitation, College of Dental Medicine, Medical University of South Carolina, Charleston, SC, USA
| |
Collapse
|
48
|
Hasanzade M, Koulivand S, Moslemian N, Alikhasi M. Comparison of three-dimensional digital technique with two-dimensional replica method for measuring marginal and internal fit of full coverage restorations. J Adv Prosthodont 2020; 12:173-180. [PMID: 32601537 PMCID: PMC7314633 DOI: 10.4047/jap.2020.12.3.173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/07/2020] [Accepted: 04/29/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSE This study compared digital (reference point matching) and replica methods for measuring marginal and internal fit of full coverage restorations. MATERIALS AND METHODS A maxillary left first molar typodent was fixed on to an aluminum base and prepared to receive all-ceramic full coverage restoration. The model was scanned with an intraoral scanner (CEREC Omnicam, Sirona, York, PA, USA). Twelve crowns were fabricated from lithium disilicate blocks (IPS emax CAD, Ivoclar Vivadent) and then crystalized. Marginal and internal fit of each restoration was measured by two examiners using replica and a new digital three-dimensional technique. Reliability between the two methods and two examiners was assessed by correlation and Cronbach's Alpha coefficient (P<.05). A Bland-Altman assessment for agreement was used to compare the two methods. RESULTS Bland-Altman assessment showed that the mean of difference for marginal, absolute marginal, and axial gap was respectively -1.04 µm, -41.9 µm, and -29.53 µm with limit of agreement (LOA) between -37.26 to 35.18 µm for marginal, -105.85 to 22.05 µm for absolute marginal and -80.52 to 22.02 µm for axial gap. Positive correlation for repeatability (P<.05) in determining marginal and internal gaps by the two examiners in both techniques was revealed. Reliability of both techniques in all sites of measurements was at least good (0.8 ≤ α < 0.9). CONCLUSION Both measuring techniques appeared highly reliable for evaluating fit of fixed dental restorations, while reference point matching provided higher values in axial and absolute marginal gap assessment.
Collapse
Affiliation(s)
- Mahya Hasanzade
- Dental Research Center, Dentistry Research Institute, Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Soudabeh Koulivand
- Department of Prosthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Naeime Moslemian
- Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Marzieh Alikhasi
- Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
49
|
Yildirim B. Effect of porcelain firing and cementation on the marginal fit of implant-supported metal-ceramic restorations fabricated by additive or subtractive manufacturing methods. J Prosthet Dent 2020; 124:476.e1-476.e6. [PMID: 32451142 DOI: 10.1016/j.prosdent.2020.03.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 12/15/2022]
Abstract
STATEMENT OF PROBLEM Adaptation between abutment and suprastructure plays a crucial role in the long-term success of implant-supported metal-ceramic crowns. Fabrication methods, the porcelain firing stage, and cementation techniques may affect the marginal adaptation between the crown and abutment. However, the information regarding this issue is sparse. PURPOSE The purpose of this in vitro study was to compare marginal fit after the fabrication of cobalt-chromium alloy copings, porcelain firing, and cementation of metal-ceramic restorations that were fabricated with computer-aided design and computer-aided manufacturing (CAD-CAM) milling and direct metal laser sintering techniques. MATERIAL AND METHODS Thirty straight tissue-level titanium abutments were screwed onto implant analogs. All specimens were embedded in acrylic resin and divided into 2 groups according to CAD-CAM milling and direct metal laser sintering fabrication of the metal coping. Fifteen cobalt-chromium implant-supported metal copings were fabricated by using the CAD-CAM milling technique and 15 by using the direct metal laser sintering technique. In both groups, marginal gap measurements between the cobalt-chromium copings and abutments were obtained before (T0) and after the placement of the ceramic veneer (T1) and after cementation (T2) by using a stereomicroscope with a magnification of ×40. The data were statistically evaluated by using 2-way ANOVA and the Tukey post hoc test (α=.05). A t test was used to determine whether there were significant differences between the fabrication techniques (α=.05). RESULTS A significant difference in the fabrication stages was found in the direct metal laser sintering group. The direct metal laser sintering coping group and porcelain applied direct metal laser sintering group had a statistically lower marginal gap value than the cemented direct metal laser sintering group (P=.021, P=.038). The direct metal laser sintering coping group had a lower marginal gap value than the CAD-CAM milling coping group, although the difference was not statistically significant (P=.216). CONCLUSIONS Porcelain firing and cementation increased the marginal gap between the crown and abutment. No statistically significant differences were found between the direct metal laser sintering and CAD-CAM milling techniques in terms of marginal fit.
Collapse
Affiliation(s)
- Bengisu Yildirim
- Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Usak University, Usak, Turkey.
| |
Collapse
|
50
|
Yuan F, Dai N, Tian S, Zhang B, Sun Y, Yu Q, Liu H. Personalized design technique for the dental occlusal surface based on conditional generative adversarial networks. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2020; 36:e3321. [PMID: 32043311 DOI: 10.1002/cnm.3321] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 12/14/2019] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
The tooth defect is a frequently occurring disease within the field of dental clinic. However, the traditional manual restoration for the defective tooth needs an especially long treatment time, and dental computer aided design and manufacture (CAD/CAM) systems fail to restore the personalized anatomical features of natural teeth. Aiming to address the shortcomings of existed methods, this article proposes an intelligent network model for designing tooth crown surface based on conditional generative adversarial networks. Then, the data set for training the network model is constructed via generating depth maps of 3D tooth models scanned by the intraoral. Through adversarial training, the network model is able to generate tooth occlusal surface under the constraint of the space occlusal relationship, the perceptual loss, and occlusal groove filter loss. Finally, we carry out the assessment experiments for the quality of the occlusal surface and the occlusal relationship with the opposing tooth. The experimental results demonstrate that our method can automatically reconstruct the personalized anatomical features on occlusal surface and shorten the treatment time while restoring the full functionality of the defective tooth.
Collapse
Affiliation(s)
- Fulai Yuan
- College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China
| | - Ning Dai
- College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China
| | - Sukun Tian
- College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China
| | - Bei Zhang
- College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China
| | - Yuchun Sun
- Peking University School and Hospital of Stomatology, Beijing, People's Republic of China
| | - Qing Yu
- Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
| | - Hao Liu
- College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China
| |
Collapse
|