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Ilie N. Influence of surface finishing on the outcome of a 3-point bending test in polymer-based dental composits assessed by qualitative and quantitative fractography. J Mech Behav Biomed Mater 2024; 156:106607. [PMID: 38830315 DOI: 10.1016/j.jmbbm.2024.106607] [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: 04/12/2024] [Revised: 05/24/2024] [Accepted: 05/29/2024] [Indexed: 06/05/2024]
Abstract
OBJECTIVES The aim of the study was to evaluate the influence of surface finishing in three polymer-based composits (composits) on the result of a 3-point bending test using quantitative and qualitative fractography as well as microstructural characteristics. MATERIALS AND METHODS 270 rectangular specimens (n = 30) of three composits were prepared, stored and tested according to NIST No. 4877. Prior testing, the samples were subjected to three surface treatments: 1) no treatment, to preserve the oxygen inhibition layer, 2) with FEPA P1200 (ANSI equivalent grit 600) SiC paper abraded surface, and 3) polished surface. A three-point bending testing was employed, followed by quantitative (assessment of reason for failure and fracture pattern) and qualitative (fracture mirror measurements) fractography, 3D and 2D surface imaging, surface roughness, reliability and Fe-SEM analysis. The mirror radius that runs in the direction of constant stress was used to calculate the mirror constant (A) using Orr's equation. Uni- and multifactorial ANOVA, Tukey's post hoc test, and Weibull analysis was performed for statistical analysis. RESULTS Surface finishing has less influence on the fracture pattern, reliability and mechanical parameters and has no influence on the mirror constant. The amount of inorganic filler has a direct impact on flexural strength and modulus, while the ranking of materials was independent of surface treatment. Failures initiated by volume defects were the most common failure mode (77.0%) with surface defects accounting for 14.9% (edge) and 7.7% (corner). Polishing resulted in lower peak-to valley height compared to no treatment, both 3-4 times lower compared to the 600 grit treatment. The increase in roughness within the analyzed range did not lead to an increase in surface-related failures. CONCLUSIONS The clear dominance of volume defects in all examined materials as a cause of material fracture reduces the impact of roughness on the measured properties. This insight was only possible using qualitative and quantitative research fractography.
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Affiliation(s)
- Nicoleta Ilie
- Department of Conservative Dentistry, University Hospital, Ludwig-Maximilians-University, Goethestr. 70, D-80336, Munich, Germany.
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Jiang Y, Bao X, Yu Y, Zhang Y, Liu M, Meng F, Wang B, Chen J. Effects of different plasma treatments on bonding properties of zirconia. Heliyon 2024; 10:e32493. [PMID: 38975209 PMCID: PMC11225731 DOI: 10.1016/j.heliyon.2024.e32493] [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: 11/05/2023] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 07/09/2024] Open
Abstract
This in vitro study was to evaluate the effect of different non-thermal atmospheric pressure plasma (NTP) on shear bond strength (SBS) between yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) and self-adhesive resin cement. In this study, The Y-TZP specimens were divided into 4 groups according to the surface treatment methods as follows: Control (no surface treatment), Sb (Sandblasting), AP(argon NTP), and CP(20 % oxygen and 80 % argon combination NTP). Y-TZP specimens were randomly selected from each group to observe and test the following indexes: scanning electron microscope to observe the surface morphology; atomic force microscope to detect the surface roughness; contact angle detector to detect the surface contact angle; energy spectrometer to analyze the surface elements. Then, resin cement (Rely X-U200) was bonded to human isolated teeth with Y-TZP specimens to measure SBS. The results showed that for the SE test, the NTP group was significantly higher than the control group (p < 0.05). The results of the SBS test showed that the SBS values of the NTP group were significantly higher than those of the other groups, regardless of the plasma treatment (p < 0.05). However, there was no significant difference between groups AP and CP in a test of SBS (p > 0.05). This study shows that non-thermal atmospheric pressure plasma can improve the shear bond strength of Y-TZP by increasing the surface energy. The addition of oxygen ratio to argon is more favorable to increase the shear bond strength and is worth further investigation.
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Affiliation(s)
- Yulin Jiang
- Chongqing University Central Hospital, Chongqing Emergency Medical Center, 400014, Chongqing Province, China
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Xudong Bao
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Yang Yu
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Yannan Zhang
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Min Liu
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Fanhao Meng
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Bo Wang
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
| | - Jianfeng Chen
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning Province, China
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Ghezzi B, Meglioli M, Salvaterra Toffoli A, Mergoni G, Rossi F, Manfredi M, Lumetti S, Manfredi E. Polishing methods for composites restoration: the influence on human gingival fibroblasts behaviour. BMC Oral Health 2024; 24:651. [PMID: 38831398 PMCID: PMC11149303 DOI: 10.1186/s12903-024-04418-z] [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: 02/23/2024] [Accepted: 05/27/2024] [Indexed: 06/05/2024] Open
Abstract
BACKGROUND Carious/Non-carious cervical lesions with gingival recessions may require both dental and periodontal reconstructive therapy, where flaps/grafts may be placed in contact with a dental filling material. Human Gingival Fibroblasts (HGF-1) response during the early phase of healing could vary according to the procedures employed to cure the dental composite. Moreover, oxygen diffusion into dental composite inhibits the polymerization reaction, creating an oxygen-inhibited layer (OIL) that presents residual unreacted monomers. The aim of this study was to assess the effect of different polishing techniques and OIL on HGF-1. METHODS Composite discs polished with different techniques (diamond rubber, abrasive discs and tungsten carbide burr) were used. An additional not polished smooth group obtained with and without OIL was used as control. Samples were physically characterized through the analysis of their hydrophilicity and surface topography through contact angle measurement and SEM, respectively; afterwards the biologic response of HGF-1 when cultured on the different substrates was analyzed in terms of cytotoxicity and gene expression. RESULTS The finishing systems caused alterations to the wettability, even if without a proportional relation towards the results of the proliferation essay, from which emerges a greater proliferation on surfaces polished with one-step diamond rubber and with abrasive discs as well as a direct effect of the glycerin layer, confirming that surface roughness can heavily influence the biological response of HGF-1. CONCLUSIONS Surfaces wettability as well as cellular behavior seem to be affected by the selection of the finishing system used to lastly shape the restoration. Especially, the presence of OIL act as a negative factor in the regards of human gingival fibroblasts. The present study may provide the first clinical instruction regarding the best polishing system of composite material when the restoration is placed directly in contact with soft tissue cells. Understanding HGF-1 behavior can help identifying the polishing treatment for direct restoration of carious/non-carious cervical lesions associated with gingival recessions.
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Affiliation(s)
- Benedetta Ghezzi
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy.
- IMEM-CNR, Institute of Materials for Electronics and Magnetism, National Research Council, Parco Area delle Scienze 37/A, Parma, 43124, Italy.
| | - Matteo Meglioli
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy
| | - Andrea Salvaterra Toffoli
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy
| | - Giovanni Mergoni
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy
| | - Francesca Rossi
- IMEM-CNR, Institute of Materials for Electronics and Magnetism, National Research Council, Parco Area delle Scienze 37/A, Parma, 43124, Italy
| | - Maddalena Manfredi
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy
| | - Simone Lumetti
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy
- IMEM-CNR, Institute of Materials for Electronics and Magnetism, National Research Council, Parco Area delle Scienze 37/A, Parma, 43124, Italy
| | - Edoardo Manfredi
- Department of Medicine and Surgery, Centre for Dental Medicine, University of Parma, Via Gramsci 14, Parma, 43126, Italy
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Haugli KH, Alkarra D, Samuelsen JT. Digital manufacturing techniques and the in vitro biocompatibility of acrylic-based occlusal device materials. Clin Oral Investig 2024; 28:312. [PMID: 38748326 PMCID: PMC11096251 DOI: 10.1007/s00784-024-05707-1] [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: 11/15/2023] [Accepted: 05/06/2024] [Indexed: 05/18/2024]
Abstract
OBJECTIVES Material chemistry and workflow variables associated with the fabrication of dental devices may affect the biocompatibility of the dental devices. The purpose of this study was to compare digital and conventional workflow procedures in the manufacturing of acrylic-based occlusal devices by assessing the cytotoxic potential of leakage products. METHODS Specimens were manufactured by 3D printing (stereolithography and digital light processing), milling, and autopolymerization. Print specimens were also subjected to different post-curing methods. To assess biocompatibility, a human tongue epithelial cell line was exposed to material-based extracts. Cell viability was measured by MTT assay while Western blot assessed the expression level of selected cytoprotective proteins. RESULTS Extracts from the Splint 2.0 material printed with DLP technology and post-cured with the Asiga Flash showed the clearest loss of cell viability. The milled and autopolymerized materials also showed a significant reduction in cell viability. However, by storing the autopolymerized material in dH2O for 12 h, no significant viability loss was observed. Increased levels of cytoprotective proteins were seen in cells exposed to extracts from the print materials and the autopolymerized material. Similarly to the effect on viability loss, storing the autopolymerized material in dH2O for 12 h reduced this effect. CONCLUSIONS/CLINICAL RELEVANCE Based on the biocompatibility assessments, clinical outcomes of acrylic-based occlusal device materials may be affected by the choice of manufacturing technique and workflow procedures.
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Affiliation(s)
- Ketil Hegerstrøm Haugli
- NIOM, Nordic Institute of Dental Materials, Oslo, Norway.
- Dental Technology Program, Faculty of Health Sciences, Oslo Metropolitan University (OsloMet), OsloMet Box 4, St. Olavs plass, Oslo, 0130, Norway.
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Néma V, Kunsági-Máté S, Őri Z, Kiss T, Szabó P, Szalma J, Fráter M, Lempel E. Relation between internal adaptation and degree of conversion of short-fiber reinforced resin composites applied in bulk or layered technique in deep MOD cavities. Dent Mater 2024; 40:581-592. [PMID: 38368136 DOI: 10.1016/j.dental.2024.02.013] [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: 10/01/2023] [Revised: 01/08/2024] [Accepted: 02/12/2024] [Indexed: 02/19/2024]
Abstract
OBJECTIVE The purpose was to evaluate the degree of conversion (DC), internal adaptation (IA) and closed porosity (CP) of short-fiber reinforced resin composites (SFRC) associated with layered or bulk restorative procedures in deep MOD cavities. METHODS Eighty third molars with standardized MOD cavities (5-mm-depth, 2.5-mm-width) were randomly divided into four groups and restored as follows: 1) bulk SFRC; 2) layered SFRC; 3) flowable bulk-fill resin-based composites (RBC); 4) layered conventional RBC. After one-month wet storage the samples were subjected to micro-computed tomography measurements and scanning electron microscopy to assess the IA and CP. Micro-Raman spectroscopy was used to determine the DC in different depths. Data were subjected to ANOVA and Tukey's post-hoc test, multivariate analysis and partial eta-squared statistics (p < 0.05). Pearson correlation coefficient was determined to assess the relationship among the parameters of interest. RESULTS Gap/total interface volume ratio ranged between 0.22-0.47%. RBCs applied in bulk revealed significantly lower gap volume (p < 0.001) and CP (p < 0.05). Each group showed complete detachment on the pulpal and partial on the lateral walls, except for group3. While the highest DC% was achieved by the conventional RBC (87.2%), followed by the flowable bulk-fill (81.2%), SFRC provided the best bottom to top DC ratio (bulk: 96.4%, layered: 98.7%). The effect of factors studied (RBC type, filling technique) on IA and DC was significant (p < 0.001). SIGNIFICANCE Bulk placement of RBCs exhibited lower interfacial gap volume and achieved satisfactory DC without significant correlation between these parameters. Incremental insertion of SFRC had no advantage over bulk placement in terms of IA and DC.
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Affiliation(s)
- Viktória Néma
- Department of Operative and Esthetic Dentistry, Faculty of Dentistry, University of Szeged, Tisza Lajos Blvd 64-66, 6720 Szeged, Hungary
| | - Sándor Kunsági-Máté
- Department of Organic and Pharmacological Chemistry, University of Pécs Medical School, Faculty of Pharmacy, Honvéd street 1, 7624 Pécs, Hungary; János Szentágothai Research Center, University of Pécs, Ifjúság Street 12, 7624 Pécs, Hungary
| | - Zsuzsanna Őri
- Department of Nutritional Sciences and Dietetics, University of Pécs, Faculty of Health Sciences, Vörösmarty Street 4, 7621 Pécs, Hungary; Department of Physical Chemistry and Materials Science, University of Pécs, Faculty of Sciences, Ifjúság Street 6, 7624 Pécs, Hungary
| | - Tamás Kiss
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, Szigeti Street 12, 7624 Pécs, Hungary
| | - Péter Szabó
- János Szentágothai Research Center, University of Pécs, Ifjúság Street 12, 7624 Pécs, Hungary
| | - József Szalma
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, 7623 Pécs, Hungary
| | - Márk Fráter
- Department of Operative and Esthetic Dentistry, Faculty of Dentistry, University of Szeged, Tisza Lajos Blvd 64-66, 6720 Szeged, Hungary
| | - Edina Lempel
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, 7623 Pécs, Hungary.
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Lim B, Kim D, Song JS, Kim S, Kim H, Shin Y. Influence of Post-Curing in Nitrogen-Saturated Condition on the Degree of Conversion and Color Stability of 3D-Printed Resin Crowns. Dent J (Basel) 2024; 12:68. [PMID: 38534292 DOI: 10.3390/dj12030068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/19/2024] [Accepted: 03/04/2024] [Indexed: 03/28/2024] Open
Abstract
Post-curing is the process of applying extra light to complete the polymerization process of 3D printing. The mechanical properties of light-cured three-dimensional (3D) printed resin can be improved by decreasing the oxygen concentrations during post-curing, and nitrogen-saturated post-curing has been applied for this purpose. This study aimed to evaluate and compare the color stability of 3D-printed resin crowns that were post-cured in both normal air and nitrogen-saturated conditions. Crowns were fabricated with a 3D printer and post-cured in normal air (control group; air) or nitrogen-saturated conditions (experimental group; nitrogen). The specimens in each group were subdivided into four subgroups, each exposed to different discoloration agents: distilled water, coffee, wine, and curry. Post-immersion color changes were measured using a digital spectrophotometer and analyzed using repeated-measures ANOVA. Fourier transform infrared (FT-IR) spectroscopy evaluated the degree of conversion of resin over immersion times for both post-curing conditions. Upon comparing the effects of post-curing conditions, a significant difference between the control and experimental groups in terms of immersion time in the wine and curry subgroups was found. FT-IR analysis showed a significant difference in the degree of conversion between the air and nitrogen groups from 10 to 300 s. These findings suggest that nitrogen-saturated post-curing can potentially enhance the conversion rate of 3D-printed resin crowns, thereby improving their color stability.
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Affiliation(s)
- Bohyun Lim
- Department of Conservative Dentistry, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Dohyun Kim
- Department of Conservative Dentistry, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Je Seon Song
- Department of Pediatric Dentistry, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Sunil Kim
- Department of Conservative Dentistry, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Hoon Kim
- Research Institute of Agriculture and Life Sciences, College of Agriculture & Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Yooseok Shin
- Department of Conservative Dentistry, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
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Tang C, Mercelis B, Yoshihara K, Peumans M, Van Meerbeek B. Does the universal adhesive's film thickness affect dentin-bonding effectiveness? Clin Oral Investig 2024; 28:150. [PMID: 38358575 DOI: 10.1007/s00784-024-05523-7] [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: 11/24/2023] [Accepted: 01/19/2024] [Indexed: 02/16/2024]
Abstract
OBJECTIVES To investigate the influence of adhesive resin application modalities on the film thickness of the adhesive resin and the effectiveness of a two-step universal adhesive (UA) bonded in self-etch (SE) bonding mode to high C-factor class-I cavity-bottom dentin. MATERIALS AND METHODS After application of the primer of G2-Bond Universal (G2B, GC), the adhesive resin was applied into standard class-I cavities (human molars) following four application modalities: (1) one layer, strongly air-blown; (2) one layer, gently air-blown; (3) two layers, each gently air-blown; (4) one layer, not air-blown. After being restored with composite, each tooth was sectioned to obtain one micro-specimen (n = 10), of which the adhesive resin film thickness was measured using optical microscopy. The micro-tensile bond strength (μTBS) was tested immediately or upon 100,000 thermocycles. Statistical analyses involved Kruskal-Wallis and Mann-Whitney U testing (p < 0.05). RESULTS G2B's μTBS was significantly affected by the adhesive resin application modality and aging. Gently air-blowing the adhesive resin resulted in significantly higher immediate μTBS than strong air-blowing or no air-blowing. No significant difference in μTBS was found between single or double gently air-blown adhesive resin applications. The adhesive resin film thickness significantly varied with the application modalities. CONCLUSIONS A too thin or too thick adhesive resin film thickness adversely affected bond strength of the two-step UA applied in SE mode and high C-factor condition. CLINICAL RELEVANCE The adhesive resin layer thickness can affect the bonding performance of two-step UAs in high C-factor cavities. Dental clinicians remain advised to avoid improper air-blowing of UAs and strictly follow the application instructions.
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Affiliation(s)
- Chuliang Tang
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7 blok a - bus 7001, Leuven, 3000, Belgium
| | - Ben Mercelis
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7 blok a - bus 7001, Leuven, 3000, Belgium
| | - Kumiko Yoshihara
- National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Takamatsu, Kagawa, 761-0395, Japan
- Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, Okayama, 700-8558, Japan
| | - Marleen Peumans
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7 blok a - bus 7001, Leuven, 3000, Belgium
| | - Bart Van Meerbeek
- KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT - Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7 blok a - bus 7001, Leuven, 3000, Belgium.
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Dunavári EK, Kőházy A, Vecsernyés M, Szalma J, Lovász BV, Berta G, Lempel E. Does Preheating Influence the Cytotoxic Potential of Dental Resin Composites? Polymers (Basel) 2024; 16:174. [PMID: 38256973 PMCID: PMC10820920 DOI: 10.3390/polym16020174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/01/2024] [Accepted: 01/04/2024] [Indexed: 01/24/2024] Open
Abstract
Resin-based dental composites (RBC) release cytotoxic components, however the extent of the elution from preheated RBCs is barely investigated. The aim was therefore to determine the cytotoxic effect of preheated conventional, bulk, and thermoviscous RBCs of clinically relevant sizes using different cell viability methods in a contact-free model. Samples (6 × 4 mm) were prepared from conventional [Estelite Sigma Quick (ESQ), Filtek Z250 (FZ)] and bulk-filled [Filtek One BulkFill Restorative (FOB), SDR Plus Bulk Flow (SDR), VisCalor Bulk (VCB)] RBCs. The pre-polymerization temperature was set to room temperature (RT) and 55/65 °C. Pulp cells were cultured, followed by a 2-day exposure to monomers released from solid RBC specimens suspended in the culture medium. Cytotoxicity was assessed using a WST-1, MTT, and LDH colorimetric viability assays. Data were analyzed using one-way ANOVA, Tukey's post hoc test, multivariate analysis, and independent t-test. The effect size (ƞp2) of material and temperature factors was also assessed. All the RBCs demonstrated cytotoxic effect upon exposure to pulp cells, but to a varying extent (ESQ >> VCB > FZ = FOB = SDR). The effect of pre-polymerization temperature was insignificant (ƞp2 < 0.03), except for the thermoviscous RBC, which showed inconsistent findings when subjected to distinct viability tests. Cell viability was predominantly dependent on the type of material used (p < 0.001) which showed a large effect size (ƞp2 > 0.90). Irrespective of the pre-polymerization temperature, RBC samples in a clinically relevant size can release monomers to such an extent, which can substantially decrease the cytocompatibility.
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Affiliation(s)
- Erika Katalin Dunavári
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary; (E.K.D.); (A.K.)
| | - Anna Kőházy
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary; (E.K.D.); (A.K.)
| | - Mónika Vecsernyés
- Department of Medical Biology and Central Electron Microscope Laboratory, University of Pécs Medical School, Szigeti Street 12, 7624 Pécs, Hungary; (M.V.); (G.B.)
| | - József Szalma
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary;
| | - Bálint Viktor Lovász
- Oral and Maxillofacial Department, Manchester University Foundation Trust, Manchester Royal Infirmary Hospital, Oxford Rd, Manchester M13 9WL, UK;
| | - Gergely Berta
- Department of Medical Biology and Central Electron Microscope Laboratory, University of Pécs Medical School, Szigeti Street 12, 7624 Pécs, Hungary; (M.V.); (G.B.)
| | - Edina Lempel
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary; (E.K.D.); (A.K.)
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Eslami S, Kopp S, Goteni M, Dahmer I, Sayahpour B. Alterations in the surface roughness and porosity parameters of directly printed and Invisalign aligners after 1 week of intraoral usage: An in vivo prospective investigation. Am J Orthod Dentofacial Orthop 2024; 165:73-79. [PMID: 37665312 DOI: 10.1016/j.ajodo.2023.07.013] [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: 03/01/2023] [Revised: 07/01/2023] [Accepted: 07/01/2023] [Indexed: 09/05/2023]
Abstract
INTRODUCTION Direct printing of clear aligners could be the next paradigm shift in modern orthodontics and can potentially overcome the limitation of the indirect production method. This study investigated the effects of 1 week of intraoral usage on the surface roughness parameters of directly printed aligners (DPAs) and commercially produced Invisalign aligners compared with their unused control counterparts using confocal laser scanning microscopy. METHODS The study consisted of 4 groups with 34 samples per group. Unused control aligners were allocated to the control groups (DP-Ctr and INV-Ctr). Sixty-eight patients undergoing clear aligner therapy were allocated to group DP-Clin (patients in therapy using DPAs made from TC-85 DAC resin) and group INV-Clin (patients provided with Invisalign aligners). After 1 week of intraoral usage, the aligners were retrieved from the patients in groups DP-Clin and INV-Clin. Samples were made from the buccal surface of the maxillary right central incisor of each aligner and underwent surface roughness and porosity measuring using confocal laser scanning microscopy. The arithmetic mean deviation of the profile, root mean square deviation, maximum peak height, maximum valley depth, maximum height difference among the highest peak and deepest valley, void volume, and void count were measured. Descriptive analysis and median (quantile) regression models were used for data analysis of this experiment. RESULTS One week of intraoral usage significantly increased the surface roughness and porosity of DPAs. In contrast, a significant reduction in the surface roughness and porosity parameters of Invisalign aligners was recorded after intraoral service. CONCLUSIONS This study suggests an increase in the surface roughness and surface porosity of DPAs following 1 week of intraoral usage, which might lead to an increase in bacterial adhesion and biofilm formation in these aligners.
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Affiliation(s)
- Sara Eslami
- Department of Orthodontics, Johann-Wolfgang Goethe University, Frankfurt, Germany.
| | - Stefan Kopp
- Department of Orthodontics, Johann-Wolfgang Goethe University, Frankfurt, Germany
| | | | - Iulia Dahmer
- Department of Orthodontics, Johann-Wolfgang Goethe University, Frankfurt, Germany
| | - Babak Sayahpour
- Department of Orthodontics, Johann-Wolfgang Goethe University, Frankfurt, Germany
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Narkedamalli RK, Muliya VS, Pentapati KC. Staining ability of herbal tea preparations on a nano-filled composite restorative material - an in-vitro study. F1000Res 2023; 11:1376. [PMID: 37638138 PMCID: PMC10457558 DOI: 10.12688/f1000research.128029.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/23/2023] [Indexed: 08/29/2023] Open
Abstract
Background: Discoloration of tooth-colored restorations due to various factors is one of the principal causes behind the failure of aesthetics. There has been an surge in the consumption of herbal beverages in recent times and the dietary factors play a potential role in the discoloration tooth-coloured restorations. This study was done to juxtapose the staining ability of green tea (GT), moringa tea (MT), and hibiscus tea (HT) on a nano-filled composite restorative material. Methods: The study was conducted in-vitro on composite samples prepared using moulds. 112 discs were prepared from Filtek TM Z350XT composite using a brass mould lined with mylar strips. Samples were divided into GT, MT, HT, and artificial saliva (AS) groups and immersed in freshly prepared beverages for 15 minutes each day for 45 days. Digital reflectance spectrophotometer was utilized to record color at baseline, 30, and 45 days. Repeated-measures ANOVA with a post-hoc Bonferroni test was used to compare groups within each group. ANOVA with a post-hoc Games Howell test was used to compare mean differences in ΔE among the groups. Results: Maximum discoloration was observed in the GT, followed by HT and MT, with the least being in the AS group at the end of 30 and 45 days (P<0.001 and P<0.001) respectively. Conclusions: The universal nano-filled composite material showed clinically detectable discoloration when exposed to Green Tea, Hibiscus Tea, and Moringa Tea which increased with time. Herbal beverages have the potential to cause discoloration of the composite resin which is often the choice of material for anterior aesthetic restorations.
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Affiliation(s)
- Raj Kumar Narkedamalli
- Conservative Dentistry & Endodontics, Manipal College of Dental Sciences, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Vidya Saraswathi Muliya
- Conservative Dentistry & Endodontics, Manipal College of Dental Sciences, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Kalyana Chakravarthy Pentapati
- Public Health Dentistry, Manipal College of Dental Sciences, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
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Şenol AA, Karabulut Gençer B, Tarçın B, Kahramanoğlu E, Yılmaz Atalı P. Microleakage and Marginal Integrity of Ormocer/Methacrylate-Based Bulk-Fill Resin Restorations in MOD Cavities: SEM and Stereomicroscopic Evaluation. Polymers (Basel) 2023; 15:polym15071716. [PMID: 37050330 PMCID: PMC10096632 DOI: 10.3390/polym15071716] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 04/14/2023] Open
Abstract
This in vitro study aimed to compare the microleakage and marginal integrity of methacrylate/ormocer-based bulk-fill composite (BFC) restorations used in cervical marginal relocation with two different layering thicknesses in mesio-occlusal-distal (MOD) cavities exposed to thermo-mechanical loading. Standard MOD cavities were prepared in 60 mandibular molars and assigned into three groups: x-tra fil/AF + x-tra base/XB, Tetric N-Ceram Bulk Fill/TNB + Tetric N-Flow Bulk Fill/TFB, and Admira Fusion x-tra/AFX + Admira Fusion x-base/AFB. Each group was further divided into two subgroups (2 mm and 4 mm) based on the thickness of flowable BFCs (n = 10). The specimens were subjected to thermo-mechanical loading (240,000 cycles) and immersed in 0.2% methylene blue. Following mesiodistal sectioning, the specimens were examined under stereomicroscope (×25) and scored (0-3) for microleakage. Marginal integrity was examined using a scanning electron microscope (SEM). Descriptive statistical methods and the chi-square test were used to evaluate the data (p < 0.05). While there was no statistically significant difference in gingival cement microleakage in the XB and AFB specimens with a 4 mm thickness, microleakage was significantly increased in the TFB specimen (p = 0.604, 0.481, 0.018 respectively). A significantly higher amount of score 0 coronal microleakage was detected in the AFX2 mm + AFB4 mm compared to the TNB2 mm + TFB4 mm (p = 0.039). The SEM examination demonstrated better marginal integrity in groups with 2 mm thick flowable BFCs. Ormocer and methacrylate-based materials can be used in marginal relocation with thin layers.
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Affiliation(s)
- Aslı A Şenol
- Department of Restorative Dentistry, Faculty of Dentistry, Marmara University, Istanbul 34854, Turkey
| | - Büşra Karabulut Gençer
- Department of Restorative Dentistry, Faculty of Dentistry, Nişantaşı University, Istanbul 34398, Turkey
| | - Bilge Tarçın
- Department of Restorative Dentistry, Faculty of Dentistry, Marmara University, Istanbul 34854, Turkey
| | - Erkut Kahramanoğlu
- Department of Prosthodontic Dentistry, Faculty of Dentistry, Marmara University, Istanbul 34854, Turkey
| | - Pınar Yılmaz Atalı
- Department of Restorative Dentistry, Faculty of Dentistry, Marmara University, Istanbul 34854, Turkey
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12
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Lempel E, Szebeni D, Őri Z, Kiss T, Szalma J, Lovász BV, Kunsági-Máté S, Böddi K. The effect of high-irradiance rapid polymerization on degree of conversion, monomer elution, polymerization shrinkage and porosity of bulk-fill resin composites. Dent Mater 2023; 39:442-453. [PMID: 36918332 DOI: 10.1016/j.dental.2023.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 02/17/2023] [Accepted: 03/03/2023] [Indexed: 03/13/2023]
Abstract
OBJECTIVE The purpose was to compare the degree of conversion (DC), monomer elution (ME), polymerization shrinkage (PS) and porosity of two addition-fragmentation chain transfer (AFCT) modified resin-based composites (RBC) light-cured with rapid- (RP), turbo- (TP) or conventional polymerization (CP) settings. METHODS Cylindrical samples (6-mm wide, 4-mm thick) were prepared from Tetric PowerFill (TPF) and Filtek One Bulk (FOB). Four groups were established according to the polymerization settings: 3s-RP, 5s-TP, 10s-CP and 20s-CP. Samples in 1 mm thickness with 20s-CP settings served as controls. The DC at the top and bottom surfaces was measured with micro-Raman spectroscopy. ME was detected with high-performance liquid chromatography. PS and porosity were analyzed by micro-computed tomography. ANOVA and Tukey's post-hoc test, multivariate analysis and partial eta-squared statistics were used to analyze the data (p < 0.05). RESULTS FOB showed higher DC values (61.5-77.5 %) at the top compared to TPF (43.5-67.8 %). At the bottom TPF samples achieved higher DCs (39.9-58.5 %) than FOB (18.21-66.18 %). Extending the curing time increased DC (except the top of FOB) and decreased ME. BisGMA release was the highest among the detected monomers from both RBCs. The amount was three-fold more from TPF. The factor Material and Exposure significantly influenced DC and ME. PS (1.8-2.5 %) did not differ among the groups and RBCs except for the lowest value of TPF cured with the 3s_RP setting (p = 0.03). FOB showed 4.5-fold lower porosity (p < 0.001). Significantly higher pore volume was detected after polymerization in 3s_RP (p < 0.001). SIGNIFICANCE High-irradiance rapid 3-s curing of AFCT modified RBCs resulted in inferior results for some important material properties. A longer exposure time is recommended in a clinical situation.
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Affiliation(s)
- Edina Lempel
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary.
| | - Donát Szebeni
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary
| | - Zsuzsanna Őri
- János Szentágothai Research Center, Ifjúság Street 12, Pécs 7624, Hungary; Department of General and Physical Chemistry, University of Pécs, Ifjúság Street 6, Pécs 7624, Hungary
| | - Tamás Kiss
- János Szentágothai Research Center, Ifjúság Street 12, Pécs 7624, Hungary
| | - József Szalma
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary
| | - Bálint Viktor Lovász
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary
| | - Sándor Kunsági-Máté
- János Szentágothai Research Center, Ifjúság Street 12, Pécs 7624, Hungary; Department of Organic and Medicinal Chemistry, University of Pécs, Faculty of Pharmacy, Honvéd Street 1, Pécs 7624, Hungary
| | - Katalin Böddi
- Department of Biochemistry and Medical Chemistry, University of Pécs Medical School, Szigeti Street 12, Pécs 7624, Hungary
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13
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Ilie N. Cytotoxic, Elastic-Plastic and Viscoelastic Behavior of Aged, Modern Resin-Based Dental Composites. Bioengineering (Basel) 2023; 10:bioengineering10020235. [PMID: 36829729 PMCID: PMC9952265 DOI: 10.3390/bioengineering10020235] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/12/2023] Open
Abstract
The development of resin-based composites (RBCs) is a delicate balance of antagonistic properties with direct clinical implications. The clear trend toward reducing filler size in modern RBCs solves esthetic deficiencies but reduces mechanical properties due to lower filler content and increases susceptibility to degradation due to larger filler-matrix interface. We evaluated a range of nano- and nano-hybrid RBCs, along with materials attempting to address shrinkage stress issues by implementing an Ormocer matrix or pre-polymerized fillers, and materials aiming to provide caries-protective benefit by incorporating bioactive fillers. The cytotoxic response of human gingival fibroblast (HGF) cells after exposure to the RBC eluates, which were collected for up to six months, was analyzed using a WST-1 assay. The microstructural features were characterized using a scanning electron microscopy and were related to the macroscopic and microscopic mechanical behaviors. The elastic-plastic and viscoelastic material behaviors were evaluated at the macroscopic and microscopic levels. The data were supplemented with fractography, Weibull analysis, and aging behavioral analysis. The results indicate that all RBCs are non-cytotoxic at adequate exposure. The amount of inorganic filler affects the elastic modulus, while only to a limited extent the flexural strength, and is well below the theoretical estimates. The nanoparticles and the agglomeration of nanoparticles in the RBCs help generate good mechanical properties and excellent reliability, but they are more prone to deterioration with aging. The pre-polymerized fillers lower the initial mechanical properties but are less sensitive to aging. Only the Ormocer retains its damping ability after aging. The strength and modulus of elasticity on the one hand and the damping capacity on the other are mutually exclusive and indicate the direction in which the RBCs should be further developed.
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Affiliation(s)
- Nicoleta Ilie
- Department of Conservative Dentistry and Periodontology, University Hospital, Ludwig-Maximilians-University, D-80336 Munich, Germany
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14
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Panayi N, Cha JY, Kim KB. 3D Printed Aligners : Material science, Workflow and Clinical applications. Semin Orthod 2023. [DOI: 10.1053/j.sodo.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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15
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Dunavári E, Berta G, Kiss T, Szalma J, Fráter M, Böddi K, Lempel E. Effect of Pre-Heating on the Monomer Elution and Porosity of Conventional and Bulk-Fill Resin-Based Dental Composites. Int J Mol Sci 2022; 23:ijms232416188. [PMID: 36555828 PMCID: PMC9782750 DOI: 10.3390/ijms232416188] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/06/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
The pre-heating of dental resin-based composites (RBCs) improves adaptability to cavity walls, reducing microleakages. However, the rapid cooling of the pre-heated RBC may change the polymerization kinetics, and thus the final network configuration of the RBC. It is well known that unreacted monomers remaining in the set RBC can leach into the oral cavity. However, it is still not clear how the pre-heating and cooling of RBCs alter monomer elution (ME). Thus, the purpose was to determine the ME from room-temperature and pre-heated RBCs, in addition to determining the closed porosity (CP) volume. Bulk-filled RBCs and layered conventional RBC samples were prepared. The pre-polymerization temperature was set at 24 °C and 55/65 °C. The ME from RBC samples was assessed with high-performance liquid chromatography using standard monomers. CP was measured with micro-computed tomography. ME decreased significantly from bulk fills and increased from layered samples as a result of pre-heating. Pre-heating was unfavorable in terms of CP in most RBCs. Based on the effect size analysis, ME and CP were greatly influenced by both material composition, pre-polymerization temperature, and their interaction. While the pre-heating of high-viscosity bulk-fill RBCs is advantageous from a clinical aspect regarding biocompatibility, it increases CP, which is undesirable from a mechanical point of view.
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Affiliation(s)
- Erika Dunavári
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary
| | - Gergely Berta
- Department of Medical Biology and Central Electron Microscope Laboratory, University of Pécs Medical School, Szigeti Street 12, 7624 Pécs, Hungary
- Szentágothai Research Centre, University of Pécs, Ifjúság Street 20, 7624 Pécs, Hungary
| | - Tamás Kiss
- Szentágothai Research Centre, University of Pécs, Ifjúság Street 20, 7624 Pécs, Hungary
| | - József Szalma
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary
| | - Márk Fráter
- Department of Operative and Esthetic Dentistry, Faculty of Dentistry, University of Szeged, Tisza Lajos Street 64, 6720 Szeged, Hungary
| | - Katalin Böddi
- Department of Biochemistry and Medical Chemistry, University of Pécs Medical School, Szigeti Street 12, 7624 Pécs, Hungary
| | - Edina Lempel
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, 7624 Pécs, Hungary
- Correspondence: ; Tel.: +36-7253-9402
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16
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Carek A, Dukaric K, Miler H, Marovic D, Tarle Z, Par M. Post-Cure Development of the Degree of Conversion and Mechanical Properties of Dual-Curing Resin Cements. Polymers (Basel) 2022; 14:polym14173649. [PMID: 36080725 PMCID: PMC9460751 DOI: 10.3390/polym14173649] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/28/2022] [Accepted: 08/30/2022] [Indexed: 11/17/2022] Open
Abstract
This study investigated the effect of different curing conditions on the degree of conversion and mechanical properties of contemporary dual-curing resin cements. The material specimens were either light-cured directly, light-cured through a 1-mm lithium disilicate glass-ceramic layer, or self-cured. The degree of conversion was measured in 0.1-mm films using Fourier-transform infrared spectroscopy 1 day, 7 days, and 28 days post-cure. Specimens used to study the flexural strength and modulus were prepared according to the ISO 4049 protocol, stored for 28 days post-cure, and subjected to accelerated aging by absolute ethanol immersion. The degree of conversion values ranged between 44.3–77.8%. Flexural strength varied between 11.4–111.1 MPa, while flexural modulus amounted to 0.7–5.5 GPa. The degree of conversion was significantly affected by material type, curing conditions, and post-cure time; however, variations in curing conditions were the least influential factor. A statistically significant effect of curing conditions on the degree of conversion was identified for only one of the five materials tested, whereas the flexural strength and modulus of all tested materials were significantly reduced in the experimental groups that were light-cured through a ceramic layer or self-cured. The effect size analysis showed that mechanical properties were most affected by the material type, while the differences in curing conditions were less influential. A comparison of the degree of conversion and mechanical properties indicated that different curing conditions may lead to significantly different flexural strength and modulus, which are not necessarily accompanied by identifiable variations in the degree of conversion.
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Affiliation(s)
- Andreja Carek
- Department of Fixed Prosthodontics, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Ksenija Dukaric
- School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Helena Miler
- School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
- Correspondence:
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17
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H S Delgado A, Belmar Da Costa M, Polido MC, Mano Azul A, Sauro S. Collagen-depletion strategies in dentin as alternatives to the hybrid layer concept and their effect on bond strength: a systematic review. Sci Rep 2022; 12:13028. [PMID: 35906302 PMCID: PMC9338246 DOI: 10.1038/s41598-022-17371-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 07/25/2022] [Indexed: 01/01/2023] Open
Abstract
Strategies aiming to improve the longevity of resin-dentin adhesive interface developed so far have only been able to retard the problem. Different approaches are thus needed. The objective of this review was to determine whether the use of collagen-depletion strategies after acid-etching procedures may improve the bond strength of resin-based materials to dentin. A systematic review was planned following 2021 PRISMA statement guidelines, with a search strategy performed in five electronic databases: PubMed/Medline, Scopus, EMBASE, SciELO and IADR Abstract Archive (last search: 17/01/2022). Inclusion criteria encompassed studies which evaluated a collagen-depletion strategy in acid-etched human dentin and tensile/shear bond strength tests. Risk of bias assessment was carried out by two reviewers, working independently on an adapted five-domain risk of bias (RoB) checklist for laboratory studies. Results were synthesized qualitatively, as a meta-analysis was not possible due to limited number of studies and their RoB. A total of eight studies were eligible for inclusion in the systematic review after inclusion/exclusion criteria application. Out of these, two evaluated the effect of using NaOCl followed by an antioxidant, and the remaining six evaluated different enzymatic treatments (bromelain, chondroitinase ABC, papain, and trypsin). None of the studies reported a decrease of bond strength when a collagen-depletion strategy was used, in comparison to traditional hybrid layers (control). All enzymatic treatment studies which respected the inclusion criteria improved the bond strength to dentin. Some specific collagen-depletion strategies seem to play a favorable role in improving immediate bond strengths to dentin. Further research with sound methodology is required to consolidate these findings, since limitations in RoB and a low number of studies were found. The assessment of further proteolytic agents and long-term outcomes is also required.
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Affiliation(s)
- António H S Delgado
- Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz (IUEM), Campus Universitário, Quinta da Granja, Monte de Caparica, 2829-511, Almada, Portugal. .,Division of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK.
| | - Madalena Belmar Da Costa
- Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz (IUEM), Campus Universitário, Quinta da Granja, Monte de Caparica, 2829-511, Almada, Portugal
| | - Mário Cruz Polido
- Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz (IUEM), Campus Universitário, Quinta da Granja, Monte de Caparica, 2829-511, Almada, Portugal
| | - Ana Mano Azul
- Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz (IUEM), Campus Universitário, Quinta da Granja, Monte de Caparica, 2829-511, Almada, Portugal
| | - Salvatore Sauro
- Dental Biomaterials and Minimally Invasive Dentistry, Department of Dentistry, Cardenal Herrera-CEU University, CEU Universities, Valencia, Spain
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Yoda N, Abe Y, Suenaga Y, Matsudate Y, Hoshino T, Sugano T, Nakamura K, Okino A, Sasaki K. Resin Cement-Zirconia Bond Strengthening by Exposure to Low-Temperature Atmospheric Pressure Multi-Gas Plasma. MATERIALS 2022; 15:ma15020631. [PMID: 35057349 PMCID: PMC8778450 DOI: 10.3390/ma15020631] [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: 11/21/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 12/10/2022]
Abstract
The purpose of this study was to investigate the effect of gas species used for low-temperature atmospheric pressure plasma surface treatment, using various gas species and different treatment times, on zirconia surface state and the bond strength between zirconia and dental resin cement. Three groups of zirconia specimens with different surface treatments were prepared as follows: untreated group, alumina sandblasting treatment group, and plasma treatment group. Nitrogen (N2), carbon dioxide (CO2), oxygen (O2), argon (Ar), and air were employed for plasma irradiation. The bond strength between each zirconia specimen and resin cement was compared using a tension test. The effect of the gas species for plasma irradiation on the zirconia surface was investigated using a contact angle meter, an optical interferometer, an X-ray diffractometer, and X-ray photoelectric spectroscopy. Plasma irradiation increased the wettability and decreased the carbon contamination on the zirconia surface, whereas it did not affect the surface topography and crystalline phase. The bond strength varied depending on the gas species and irradiation time. Plasma treatment with N2 gas significantly increased bond strength compared to the untreated group and showed a high bond strength equivalent to that of the sandblasting treatment group. The removal of carbon contamination from the zirconia surface and an increase in the percentage of Zr-O2 on the zirconia surface by plasma irradiation might increase bond strength.
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Affiliation(s)
- Nobuhiro Yoda
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan; (Y.M.); (T.S.); (K.S.)
- Correspondence: ; Tel.: +81-22-717-8369
| | - Yuri Abe
- FIRST, Tokyo Institute of Technology, Yokohama 226-8502, Japan; (Y.A.); (Y.S.); (A.O.)
| | - Yuma Suenaga
- FIRST, Tokyo Institute of Technology, Yokohama 226-8502, Japan; (Y.A.); (Y.S.); (A.O.)
| | - Yoshiki Matsudate
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan; (Y.M.); (T.S.); (K.S.)
| | - Tomohiro Hoshino
- Joint Research Department of Next-Generation Dental Material Engineering, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan;
| | - Takehiko Sugano
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan; (Y.M.); (T.S.); (K.S.)
| | - Keisuke Nakamura
- Department of Advanced Free Radical Science, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan;
| | - Akitoshi Okino
- FIRST, Tokyo Institute of Technology, Yokohama 226-8502, Japan; (Y.A.); (Y.S.); (A.O.)
| | - Keiichi Sasaki
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan; (Y.M.); (T.S.); (K.S.)
- Joint Research Department of Next-Generation Dental Material Engineering, Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan;
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Vishwanath S, Kadandale S, Kumarappan SK, Ramachandran A, Unnikrishnan M, Nagesh HM. Finishing and Polishing of Composite Restoration: Assessment of Knowledge, Attitude and Practice Among Various Dental Professionals in India. Cureus 2022; 14:e20887. [PMID: 35145792 PMCID: PMC8808663 DOI: 10.7759/cureus.20887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2022] [Indexed: 11/21/2022] Open
Abstract
Aim The key to the success of a composite restoration lies in the important final step of finishing and polishing. This survey aims to assess the knowledge, attitude, and practice about finishing and polishing in composite restoration among various dental professionals in India. Materials and methods A cross-sectional questionnaire survey was conducted among various dental professionals in India. The participation of dentists was voluntary. A total of 350 responses were received, and the data were converted to Microsoft Excel 2019 program and descriptive statistics were analyzed using SPSS Version 21.0 software. Results Almost 99% of respondents know the importance of finishing and polishing procedures of composite restoration. Overall, 71% of respondents felt it is necessary to remove the surface layer to improve the surface characteristics of the composite restoration, 59.8% of professionals follow the sequential order of abrasives for finishing and polishing of composites, 74.2% use interproximal strips to finish interproximal areas of restoration, and 55.8% of professionals use polishing paste for the final polishing of composite restoration. Only 44.2% are aware of liquid polish/composite glaze, among which 12.4% of practitioners use liquid polish often. Conclusion Most of the respondents were aware of the benefits of proper finishing and polishing of composite restorations. However, still they need to follow proper sequential series of burs, abrasive points, disks, strips, and polishing pastes. The usage of surface sealants should be emphasized for enhanced results.
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20
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Zhang W, Bao B, Jiang F, Zhang Y, Zhou R, Lu Y, Lin S, Lin Q, Jiang X, Zhu L. Promoting Oral Mucosal Wound Healing with a Hydrogel Adhesive Based on a Phototriggered S-Nitrosylation Coupling Reaction. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2105667. [PMID: 34605063 DOI: 10.1002/adma.202105667] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/19/2021] [Indexed: 06/13/2023]
Abstract
The wet and highly dynamic environment of the mouth makes local treatment of oral mucosal diseases challenging. To overcome this, a photo-crosslinking hydrogel adhesive is developed inspired by the success of light-curing techniques in dentistry. The adhesive operates on a fast (within 5 s) phototriggered S-nitrosylation coupling reaction and employs imine anchoring to connect to host tissues. Unlike other often-used clinical agents that adhere weakly and for short durations, this thin, elastic, adhesive, and degradable cyclic o-nitrobenzyl-modified hyaluronic acid gel protects mucosal wounds from disturbance by liquid rinsing, oral movement, and friction for more than 24 h. The results from both rat and pig oral mucosa repair models demonstrate that this new gel adhesive creates a favorable microenvironment for tissue repair and can shorten tissue healing time. This study thus illustrates a therapeutic strategy with the potential to advance the treatment of oral mucosal defects in the clinic.
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Affiliation(s)
- Wenjie Zhang
- Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai Engineering Research Center of Advanced Dental Technology and Materials, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Bingkun Bao
- School of Biomedical Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai, 200240, China
| | - Fei Jiang
- Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai Engineering Research Center of Advanced Dental Technology and Materials, 639 Zhizaoju Road, Shanghai, 200011, China
- Jiangsu Key Laboratory of Oral Diseases, Department of General Dentistry, Affiliated Hospital of Stomatology, Nanjing Medical University, No. 140, Han Zhong Road, Nanjing, 210029, P. R. China
| | - Yiqing Zhang
- Optogenetics & Synthetic Biology Interdisciplinary Research Center, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, China
- School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, China
| | - Renjie Zhou
- Optogenetics & Synthetic Biology Interdisciplinary Research Center, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, China
- School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, China
| | - Yuezhi Lu
- Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai Engineering Research Center of Advanced Dental Technology and Materials, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Sihan Lin
- Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai Engineering Research Center of Advanced Dental Technology and Materials, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Qiuning Lin
- School of Biomedical Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai, 200240, China
| | - Xinquan Jiang
- Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai Engineering Research Center of Advanced Dental Technology and Materials, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Linyong Zhu
- School of Biomedical Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai, 200240, China
- Optogenetics & Synthetic Biology Interdisciplinary Research Center, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, China
- School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, China
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21
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Alhamed G, Massoud S, Doumani M. Spectrophotometric study determining staining tendency in different restorative materials (longitudinal in vitro study). Saudi Dent J 2021; 33:462-466. [PMID: 34803287 PMCID: PMC8589626 DOI: 10.1016/j.sdentj.2020.11.004] [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: 05/05/2020] [Revised: 10/12/2020] [Accepted: 11/01/2020] [Indexed: 11/30/2022] Open
Abstract
Aim Our aim was to measure the discolouration degrees in a packable composite, zircon, ceramic, a flowable composite, and GIC (glass isomer cement) and to determine their tendencies to discolour to provide guidance to dentists and prosthodontist for choosing proper materials for cases in which aesthetics is the main treatment goal. Materials and methods Sixty discs were fabricated from the composite, zircon, ceramic, the flowable composite, and GIC, and natural teeth were the control group. The shades were recorded using the Ivoclar Vivadent Shade Guide, and readings were recorded from a Vita Easyshade 4.0 spectrophotometer before immersion, after 1 week, 2 weeks, 3 weeks, and 24 weeks of immersion in coffee. The analysis was performed using a SPSS paired t-test and CIE 76 formula. Results The ceramic had a starting shade of B1 and kept the same colour throughout the testing period. Zircon had a starting shade of A3 and transitioned to B3 by the second week. The composite had a shade of A1, and after the first week, it was A4; in the second week and afterwards, it was C4. The flowable composite had a starting shade of A1, and after one week, the shade was B3, and then after one more week A3.5; after five months, it was A4. Conclusion The ceramic showed no change, making it ideal for aesthetic regions and anterior replacements. Zircon had the second-highest colour stability, whereas all the other materials showed variable degrees of colour and surface changes, making them not ideal choices for anterior restorations. Thus, this information can aid choices for aesthetic regions to provide the highest longevity.
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Affiliation(s)
- Ghada Alhamed
- Department of Prosthetic Dental Science, College of Dentistry, Qassim University, Qassim, Saudi Arabia
| | - Salsabil Massoud
- Department of Prosthetic Dental Science, College of Dentistry, Qassim University, Qassim, Saudi Arabia
| | - Mazen Doumani
- Alfarabi Colleges of Dentistry and Nursing - Department of Restorative Dental Sciences, Riyadh, Saudi Arabia
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22
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Ozaki A, Shishido S, Nakamura K, Harada A, Katsuda Y, Kanno T, Egusa H. Impact of adhesive primer and light-curing on polymerization kinetics of self-adhesive resin cement in association with free radical reaction. Eur J Oral Sci 2021; 129:e12828. [PMID: 34674326 DOI: 10.1111/eos.12828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 08/16/2021] [Indexed: 11/29/2022]
Abstract
This study analyzed the impact of adhesive primer and light-curing on the polymerization kinetics of urethane dimethacrylate-based self-adhesive resin cement combined with free radical reaction. Specimens were prepared by mixing the cement paste with or without adhesive primer. Subsequently, specimens were light-cured or set without light-curing. The degree of conversion (DC), Vickers hardness (Hv), and free radical concentrations were repeatedly measured up to 168 h after the curing initiation. Irrespective of the curing procedures, DC, Hv, and free radical concentration rapidly increased during the initial 30 min of curing. The specimens cured with adhesive primer and/or light-curing generally showed higher values of DC, Hv, and radical concentration than those set by chemical curing alone, especially during the initial polymerization phase. Kinetic analysis using a linear mixed model revealed that the adhesive primer had a higher coefficient estimate than light-curing, indicating that the former had a higher impact on the polymerization. Additionally, the adhesive primer alleviated the Hv reduction caused by water and air during the initial polymerization phase, although light-curing hardly prevented the polymerization inhibition. Therefore, we suggest that application of adhesive primer is beneficial to achieve higher degree of conversion and better mechanical properties of self-adhesive resin cements by enhancing free radical reactions.
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Affiliation(s)
- Akane Ozaki
- Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Shunichi Shishido
- Department of Advanced Free Radical Science, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Keisuke Nakamura
- Department of Advanced Free Radical Science, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Akio Harada
- Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Yusuke Katsuda
- Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Taro Kanno
- Department of Advanced Free Radical Science, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Hiroshi Egusa
- Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, Japan
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Xu YX, Li W, Su M. Use of two kinds of antioxidants to restore the bond strength of bleached enamel. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2021; 39:453-457. [PMID: 34409802 DOI: 10.7518/hxkq.2021.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVES This work aimed to evaluate the ability of two kinds of antioxidants, namely, grape-seed extract and sodium ascorbate, in restoring bond strength at the resin-enamel interface after bleaching. METHODS Ten groups of samples with 15 teeth per group were prepared for shear-bond-strength test at the resin-enamel interface after bleaching. The groups were as follows: control; no antioxidant; 2.5%, 5%, 10%, or 15% grape-seed extract; and 2.5%, 5%, 10%, or 15% sodium ascorbate. The peak values of shear bond strength when resin was debonded from teeth and the failure modes under a microscope were recorded. Ten other groups of teeth with two teeth per group were prepared and treated in a similar approach before resin bonding. The samples were cut vertically to the bonding interface. The structures of the bonding interface were compared by scanning electron microscopy. RESULTS No statistically significant difference in shear bond strength was found among the no-antioxidant, 2.5% grape-seed extract, and 2.5%, 5%, or 10% sodium ascorbate groups (P>0.05), which were statistically significantly lower than the control group (P<0.05). Evidence of marginal gap was observed at the resin-enamel interface, and resin tags in enamel were short, poorly defined, and fragmented. No statistically significant difference in shear bond strength was found among 5%, 10%, or 15% grape-seed extract, 15% sodium ascorbate, and control groups (P>0.05). No evidence of discontinuity was found at the adhesion interface, and resin tags in enamel were long, well defined, and structurally intact. Failure in the adhesive joint was the major debond mode in all experimental groups. CONCLUSIONS Immediately after bleaching, the bond strength of dental enamel significantly decreased. Bond strength can be restored by 5% grape-seed extract or 15% sodium ascorbate in 5 min.
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Affiliation(s)
- Ying-Xin Xu
- Center of Stomatology, Peking University Shenzhen Hospital, Guangdong Province Engineering Research Center of Oral Disease Diagnosis and Treatment, Shenzhen 518036, China
| | - Wen Li
- Center of Stomatology, Peking University Shenzhen Hospital, Guangdong Province Engineering Research Center of Oral Disease Diagnosis and Treatment, Shenzhen 518036, China
| | - Min Su
- Center of Stomatology, Peking University Shenzhen Hospital, Guangdong Province Engineering Research Center of Oral Disease Diagnosis and Treatment, Shenzhen 518036, China
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Maier E, Loumprinis N, Belli R, Petschelt A, Eliades G, Lohbauer U. Fracture toughness of dental incremental composite-composite interfaces at elevated temperatures. J Mech Behav Biomed Mater 2021; 122:104655. [PMID: 34246080 DOI: 10.1016/j.jmbbm.2021.104655] [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: 04/14/2021] [Revised: 06/16/2021] [Accepted: 06/21/2021] [Indexed: 11/26/2022]
Abstract
The aim of the present laboratory study was to mechanically characterize the interface between two dental resin-based composite (RBC) increments, and to investigate if elevated temperatures have an influence on the quality of the interface mimicking clinical filling procedure. Four RBCs (CLEARFIL MAJESTY™ Posterior, Kuraray (CMP)/Filtek™ Supreme XTE, 3M (FSX)/Grandio®SO, VOCO (GSO)/VisCalor® bulk, VOCO (VCB)) were tested with a fracture toughness test using Chevron notched beams (KI,CNB) at 23, 37 and 54 °C. KI,CNB specimens (3 × 4x25mm) with a V-shaped notch at the incremental interface were loaded until failure in a 4-point bending set-up. Failure modes were characterized using light microscopy, microstructural interface was analyzed using SEM. Statistical analysis was performed using Kolmogorov-Smirnoff test, two-way ANOVA and Tukey Post-Hoc test (p = 0.05). Mean KI,CNB ranged between 0.73 ±0.14 MPam0.5 (VCB, 23 °C) and 1.11 ± 0.11 MPam0.5 (FSX, 23 °C). The tested conventional highly filled RBCs presented fracture toughness at the incremental interface comparable to the cohesive strength of the bulk materials. VCB showed reduced interfacial fracture toughness at 23 and 37 °C, but performed well at elevated temperature of 54 °C.
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Affiliation(s)
- Eva Maier
- Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative and Restorative Dentistry, Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054, Erlangen, Germany.
| | - Nikolaos Loumprinis
- Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative and Restorative Dentistry, Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054, Erlangen, Germany; National and Kapodistrian University of Athens, Department of Biomaterials, School of Dentistry, 2 Thivon Str, 11527, Goudi, Athens, Greece
| | - Renan Belli
- Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative and Restorative Dentistry, Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054, Erlangen, Germany
| | - Anselm Petschelt
- Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative and Restorative Dentistry, Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054, Erlangen, Germany
| | - George Eliades
- National and Kapodistrian University of Athens, Department of Biomaterials, School of Dentistry, 2 Thivon Str, 11527, Goudi, Athens, Greece
| | - Ulrich Lohbauer
- Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative and Restorative Dentistry, Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054, Erlangen, Germany
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Influence of Non-Thermal Atmospheric Pressure Plasma Treatment on Retentive Strength between Zirconia Crown and Titanium Implant Abutment. MATERIALS 2021; 14:ma14092352. [PMID: 34062734 PMCID: PMC8125100 DOI: 10.3390/ma14092352] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 12/02/2022]
Abstract
The aim of this study is to investigate the effect of non-thermal atmospheric pressure plasma (NTP) on retentive strength (RS) between the zirconia crown and the titanium implant abutment using self-adhesive resin cement. Surface free energy (SFE) was calculated on 24 cube-shaped zirconia blocks, and RS was measured on 120 zirconia crown-titanium abutment assemblies bonded with G-CEM LinkAce. The groups were categorized according to the zirconia surface treatment as follows: Control (no surface treatment), NTP, Si (Silane), NTP + Si, Pr (Z-Prime Plus), and NTP + Pr. Half of the RS test assemblies were aged by thermocycling for 5000 cycles at 5–55 °C. The SFE was calculated using the Owens-Wendt method, and the RS was measured using a universal testing machine at the maximum load until failure. One-way analysis of variance (ANOVA) with post-hoc Tukey honestly significant difference (HSD) was performed to evaluate the effect of surface treatments on the SFE and RS. Independent sample t-test was used to compare the RS according to thermocycling (p < 0.05). For the SFE analysis, the NTP group had a significantly higher SFE value than the Control group (p < 0.05). For the RS test, in non-thermocycling, the NTP group showed a significantly higher RS value than the Control group (p < 0.05). However, in thermocycling, there was no significant difference between the Control and NTP groups (p > 0.05). In non-thermocycling, comparing with the NTP + Si or NTP + Pr group, there was no significant difference from the Si or Pr group, respectively (p > 0.05). Conversely, in thermocycling, the NTP + Si and NTP + Pr group had significantly lower RS than the Si and Pr group, respectively (p < 0.05). These results suggest that NTP single treatment for the zirconia crown increases the initial RS but has little effect on the long-term RS. Applied with Silane or Z-Prime Plus, NTP pre-treatment has no positive effect on the RS.
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Chen KK, Chen JH, Wu JH, Du JK. Influence of commercial adhesive with/without silane on the bond strength of resin-based composite repaired within twenty-four hours. J Dent Sci 2020; 16:877-884. [PMID: 34141101 PMCID: PMC8189866 DOI: 10.1016/j.jds.2020.12.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/20/2020] [Indexed: 11/29/2022] Open
Abstract
Background/purpose It is not clear whether the ground surface of resin-based composite (RBC) polymerized requires the application of an adhesive with/without a silane to improve bond strength. This study investigated the bond strength of RBC repaired within 24 h via the application of adhesive with/without a silane. Materials and methods Seventy RBC blocks were prepared and assigned to either 0 or 24 h repair stage. Each stage was divided into seven groups: a control group with no surface roughening or applied adhesive, a surface-roughened group with no applied adhesive, two surface-roughened groups treated with a G-aenial Bond adhesive and a BeautiBond Multi adhesive, two surface-roughened groups treated with the previously-mentioned adhesives as well as silane coupling agents, and one group treated with a Single Bond Universal silane-containing adhesive. Microtensile bond strength (μTBS) measurements were performed after the repaired RBC blocks of each group (n = 5) had been immersed in a 37 °C water bath for 24 h. The failure mode of each sample was determined, and the data were analyzed via one-way analysis of variance and Dunnett's test (p = 0.05). Results Regardless of the repair stage, the μTBS values of the adhesive-only and silane-adhesive groups did not differ significantly from those of the control group (p > 0.05). Only the no-adhesive groups exhibited a significantly time-dependent increase in adhesive failure rate. Conclusion Our results suggest that the application of adhesives either with or without silane can significantly increase the bond strength of repairs to RBCs polymerized within 24 h.
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Affiliation(s)
- Ker-Kong Chen
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Jeng-Huey Chen
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Ju-Hui Wu
- Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Department of Oral Hygiene, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Je-Kang Du
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Corresponding author. School of Dentistry, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, San-Ming District, Kaohsiung, 807, Taiwan. Fax: + 886 7 3121510.
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Ghubaryi AAA, Ingle N, Basser MA. Surface treatment of RMGIC to composite resin using different photosensitizers and lasers: A bond assessment of closed Sandwich restoration. Photodiagnosis Photodyn Ther 2020; 32:101965. [PMID: 32835880 DOI: 10.1016/j.pdpdt.2020.101965] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/10/2020] [Accepted: 08/17/2020] [Indexed: 11/20/2022]
Abstract
AIM The aim of present study was to assess and compare different conditioning methods (laser, PDT and conventional) on shear bond strength (SBS) of resin modified glass ionomer cement (RMGIC) bonded to composite (sandwich technique). MATERIAL AND METHODS Fifty specimens were prepared from RMGIC and were packed in a teflon mould placed on glass slab. Through each of the glass slab the cement was light cured for 20 s. Now samples were randomly allocated into five groups (n = 10) according to pre-treatment protocols. In group 1 RMGIC were conditioned with MBP using PDT, Samples in group 2 treated with Er,Cr:YSGG (ECYL), group 3 pre-treated with Nd:YAG laser (NYL), samples in group 4 surface conditioned with air abrasion (AA) and group 5 conditioned with 37 % phosphoric acid (PA). Specimens after conditioning were rinsed with distilled water. Adhesive Adper Single Bond 2 was applied on treated surface of RMGIC and cured. Teflon mold was utilized to hold the composite Filtek Z250 in an incremental technique. For SBS testing all specimens were placed under shear knife edge at 1 K N at a speed of 0.5mm2 until bond failure. Optical microscope was used to evaluate failure pattern at 10x magnification. The data of SBS in Megapascal were subjected to statistical test. Analysis of variance was followed by Post hoc test with level of significance at 5 %. RESULT The maximum SBS was found in group 5 RMGIC conditioned with 37 % PA (16.45 ± 0.32 MPa). Whereas, group 1 (MBP, PDT) demonstrated significantly lower bond integrity (9.82 ± 1.08 MPa) compared to all experimental groups. Bond integrity of RMGIC surface treated with MBP, PDT (9.82 ± 1.08 MPa), group 3 lased with NYL (11.47 ± 0.53 MPa) and samples in group 4 conditioned with AA (11.23 ± 0.47 MPa) were comparable (p > 0.05). CONCLUSION ECYL has a potential to be used for conditioning of RMGIC prior to composite restoration (sandwich technique). MBP at 100 mg/L deteriorates SBS of composite to RMGIC.
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Affiliation(s)
- Ahmed Ali A Ghubaryi
- Dental Public Health, College of Dentistry, Riyadh Elm University, Riyadh, Saudi Arabia.
| | - Navin Ingle
- Programme Director Dental Public Health, College of Dentistry, Riyadh Elm University, Riyadh, Saudi Arabia.
| | - Mohammed Abdul Basser
- Department of Dental Public Health, College of Dentistry, Riyadh Elm University, Riyadh, Saudi Arabia.
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Improvement of aesthetics in a patient with tetracycline stains using the injectable composite resin technique: case report with 24-month follow-up. Br Dent J 2020; 229:774-778. [DOI: 10.1038/s41415-020-2405-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 07/13/2020] [Indexed: 11/09/2022]
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Charlier Q, Lortie F, Gerard J. How does paraffin wax prevent evaporation of acrylic‐based syrups dedicated to fiber‐reinforced composite processing? J Appl Polym Sci 2020. [DOI: 10.1002/app.48685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Quentin Charlier
- Univ‐Lyon, INSA‐Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223 Villeurbanne France
| | - Frédéric Lortie
- Univ‐Lyon, INSA‐Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223 Villeurbanne France
| | - Jean‐François Gerard
- Univ‐Lyon, INSA‐Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223 Villeurbanne France
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Keul C, Seidl J, Güth JF, Liebermann A. Impact of fabrication procedures on residual monomer elution of conventional polymethyl methacrylate (PMMA)-a measurement approach by UV/Vis spectrophotometry. Clin Oral Investig 2020; 24:4519-4530. [PMID: 32424461 DOI: 10.1007/s00784-020-03317-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 04/30/2020] [Indexed: 10/24/2022]
Abstract
OBJECTIVES To analyse the residual monomer (MMA) elution of polymethyl methacrylate (PMMA) in distilled water after diverse fabrication methods and aging procedures. MATERIALS AND METHODS PMMA specimens (N = 192, PalaXpress; Kulzer, Hanau, Germany) were manufactured (pouring, n = 96/injection, n = 96) and polymerized in water (55°C) without pressure (n = 48) and with 2 bar pressure (n = 48). Specimens were grinded (n = 24) or polished (n = 24) and aged for 12 h in distilled water/37°C (n = 12) or at air/20°C (n = 12) and stored afterwards in distilled water at 37°C. MMA elution was evaluated after 1, 2, 3, 4, 5, 6, 7, 10, 15 days (UV/Vis spectrophotometry). Data were analysed with Kolmogorov-Smirnov, Mann-Whitney-U and Cohen-d test using SPSS (α < 0.5). RESULTS The pouring procedure resulted in significantly higher MMA elution than the injection procedure up to 5 days. Polymerization with a pressure of 2 bar reduced the MMA elution significantly for poured specimens. Polishing reduced the MMA elution in comparison to grinding. CONCLUSIONS The fabrication procedure (pouring/injection) showed the strongest correlation to the MMA elution (r = 0.500), followed by polishing (r = 0.243), the pressure during polymerization (r = 0.109) and the storage medium (r = 0.053). CLINICAL RELEVANCE Higher MMA elution may increase the risk of chemical irritations, allergic reactions and hypersensitivities of the oral mucosa. Technicians and dentists should be aware about the elution differences dependent on the fabrication procedure.
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Affiliation(s)
- Christine Keul
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany.
| | - Judith Seidl
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany
| | - Jan-Frederik Güth
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany
| | - Anja Liebermann
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany
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Firouzmandi M, Khashaei S. Knoop Hardness of Self-Etch Adhesives Applied on Superficial and Deep Dentin. JOURNAL OF DENTISTRY (SHIRAZ, IRAN) 2020; 21:42-47. [PMID: 32158783 PMCID: PMC7036347 DOI: 10.30476/dentjods.2019.77805.0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Statement of the Problem Low pH of self-etch adhesives might cause suboptimal polymerization. Purpose This study aimed to evaluate the effect of dentin depth (deep and superficial) on polymerization efficacy of two self-etch adhesives, with different pH by means of Knoop hardness test. Materials and Method In this in vitro study, sixty sound molars were used to prepare 30 superficial dentin and 30 deep dentin specimens. Dentin specimens of each depth were randomly distributed into two equal subgroups (N=15) and bonded by either Adper Prompt L-Pop (strong self-etch adhesive) or Adper Easy Bond (mild self-etch adhesive). Knoop hardness test was employed to evaluate degree of cross-linking of the adhesives. Data were analyzed with SPSS 16, using two-way ANOVA to compare mean hardness values of the study groups (p< 0.05). Results There was no interaction effect between dentin depth and the type of adhesive (p= 0.36). Regardless of dentin depth, hardness of Adper Easy Bond was significantly higher than that of Adper Prompt L-pop (p< 0.001). Moreover, both the adhesives showed higher hardness when bonded to superficial dentin compared to deep dentin (p< 0.001). Conclusion Degree of cross-linking of the self-etch adhesive with mild acidity was more than that of the strong self-etch adhesive after light-curing. Surface hardness of both adhesives was higher on superficial dentin compared to deep dentin.
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Affiliation(s)
- Maryam Firouzmandi
- Dept. of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Shideh Khashaei
- Graduated Dental Student, Student Research Committee, School of Dentistry, Shiraz University of Medical Science, Shiraz, Iran
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Influences of Different Air-Inhibition Coatings on Monomer Release, Microhardness, and Color Stability of Two Composite Materials. BIOMED RESEARCH INTERNATIONAL 2019; 2019:4240264. [PMID: 31211136 PMCID: PMC6532316 DOI: 10.1155/2019/4240264] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/08/2019] [Accepted: 04/18/2019] [Indexed: 12/11/2022]
Abstract
The aim of this study was to evaluate the effect of light-curing protocols on two modern resin composites using different air-inhibition coating strategies. This was accomplished by assessing the amount of monomer elution, surface microhardness, and composite discoloration in different storage conditions. A total of 120 specimens were prepared using Filtek Supreme XTE (3M ESPE, Seefeld, Germany) and CeramX Universal (Dentsply DeTrey, Konstanz, Germany). Specimens were light-cured in air as per manufacturer's instructions or in the absence of oxygen. This latter condition was achieved using three different approaches: (i) transparent polyester strip; (ii) glycerin; (iii) argon gas. Specimens were assessed for release of monomers, Vickers hardness, and discoloration after storage in different solutions. The results were analyzed with ANOVA one-way test followed by Student-Newman-Keuls test. Moreover, multiple comparisons of means were performed using the Student t-test (p<0.05). The amount of monomers released from the tested specimens was very low in all conditions. The presence of oxygen induced some decrease in microhardness. The highest discoloration values, for both materials, were obtained after ageing in red wine. In case finish and polish procedures are awkward to achieve in posteriors composite restoration, light-curing in the absence of oxygen should be considered, especially when performing composite restoration in esthetic areas.
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Papadogiannis D, Dimitriadi M, Zafiropoulou M, Gaintantzopoulou MD, Eliades G. Universal Adhesives: Setting Characteristics and Reactivity with Dentin. MATERIALS 2019; 12:ma12101720. [PMID: 31137848 PMCID: PMC6566910 DOI: 10.3390/ma12101720] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/21/2019] [Accepted: 05/22/2019] [Indexed: 01/10/2023]
Abstract
The aim of the study was to evaluate the performance of six commercially available universal dental adhesives: Adhese Universal (ADU), All-Bond Universal (ABU), Clearfil Universal Bond Quick (CBQ), G-Premio Bond (GPB), Prelude One (PRO) and Scotchbond Universal (SBU). The properties tested were: (a) degree of C=C conversion (DC%); (b) Vickers micro-hardness (VHN); (c) extent of oxygen inhibition (OI/μm), all related with the adhesive film properties; (d) extent of dentin demineralisation (DM%), insoluble salt formation (AS%); and (e) shear bond strength (SBS, self-etch mode) related to the adhesive-dentin interactions. Statistical analysis (α = 0.05) was performed by one-way ANOVA and Tukey's test (DC%, VHN, OI, DM% AS%) and Weibull analysis (SBS, σ0-β). The DC ranged from 67.2-82.5% (all >GPB), OI from 5.6-18.6 μm (SBU > ADU, GPB, ABU > CBQ > PRO), microhardness from 1.1-6.6 VHN (SBU > ADU > ABU > CBQ > PRO > GPB: not measurable), DM from 69.3% (GPB) to 16-12.5% (CBQ, SBU, ADU) and 13.2-10.6% (ABU, ADU, PRO), in homogeneous groups and AS from 26-15.9% (ABU, CBQ > GPB, PRO, ADU, SBU). For SBS the σ0 (characteristic life) ranged from 29.3-16.6 MPa (CBQ, ADU, ABU, SBU > PRO > GPB), the β (reliability) from 5.1-9.7 (p > 0.05). All failure modes were of mixed type (adhesive and composite cohesive). Although all these adhesives were based on the 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) adhesive monomer, the different co-monomers, solvents and catalysts led to variations in their film properties, reactivity and bonding capacity with dentin.
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Affiliation(s)
- Dimitris Papadogiannis
- Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, 115 27 Athens, Greece.
| | - Maria Dimitriadi
- Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, 115 27 Athens, Greece.
| | - Maria Zafiropoulou
- Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, 115 27 Athens, Greece.
| | | | - George Eliades
- Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, 115 27 Athens, Greece.
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Omran TA, Garoushi S, Lassila LV, Vallittu PK. Effect of interface surface design on the fracture behavior of bilayered composites. Eur J Oral Sci 2019; 127:276-284. [PMID: 31002749 PMCID: PMC6617810 DOI: 10.1111/eos.12617] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This study aimed to evaluate the effect of different interface designs on the load‐bearing capacity of bilayered composite structures (BLS). Cylindrical specimens of BLS were prepared from base composite of 3.5 mm thickness and surface composite of 1.5 mm thickness (n = 80). Two different base composites – flowable bulk‐fill (FBF) [smart dentin replacement (SDR)] and short fiber‐reinforced (FRC) (everX Posterior) – were evaluated, and conventional composite (G‐ænial Posterior) was used as the surface layer. Four different interface designs were used: (i) pyramidal; (ii) mesh; (iii) linear grooves; and (iv) flat surface (control). Three‐dimensional printed molds were fabricated to standardize the interface design between the surface and the base composites. The specimens were then statically loaded with a steel ball until fracture using a universal testing machine. Fracture types were classified into catastrophic, complete, and partial bulk. anova revealed that both the material and the interface design had a statistically significant effect on the load‐bearing capacity. Flowable bulk‐fill showed lower mean load‐bearing capacity than FRC in all the interface designs tested, except for the flat surface design. Fracture analysis showed that FRC demonstrated up to 100% partial bulk fractures with the pyramid interface design, but no incidence of catastrophic bulk fracture. By contrast, FBF demonstrated up to 84.6% and 40% catastrophic bulk fractures with the flat interface design but no incidence of partial bulk fracture. Consequently, the interface designs studied enhanced the fracture behavior of BLS.
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Affiliation(s)
- Tarek A Omran
- Finnish Doctoral Program in Oral Sciences (FINDOS), Turku, Finland.,Department of Biomaterials Science, Institute of Dentistry, Faculty of Medicine, University of Turku, Turku, Finland.,Turku Clinical Biomaterials Centre (TCBC), Turku, Finland
| | - Sufyan Garoushi
- Department of Biomaterials Science, Institute of Dentistry, Faculty of Medicine, University of Turku, Turku, Finland.,Turku Clinical Biomaterials Centre (TCBC), Turku, Finland
| | - Lippo V Lassila
- Department of Biomaterials Science, Institute of Dentistry, Faculty of Medicine, University of Turku, Turku, Finland.,Turku Clinical Biomaterials Centre (TCBC), Turku, Finland
| | - Pekka K Vallittu
- Department of Biomaterials Science, Institute of Dentistry, Faculty of Medicine, University of Turku, Turku, Finland.,Turku Clinical Biomaterials Centre (TCBC), Turku, Finland.,City of Turku Welfare Division, Oral Health Care, Turku, Finland
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Factors affecting the color stability and staining of esthetic restorations. Odontology 2019; 107:507-512. [DOI: 10.1007/s10266-019-00421-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/10/2019] [Indexed: 12/22/2022]
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Panpisut P, Khan MA, Main K, Arshad M, Xia W, Petridis H, Young AM. Polymerization kinetics stability, volumetric changes, apatite precipitation, strontium release and fatigue of novel bone composites for vertebroplasty. PLoS One 2019; 14:e0207965. [PMID: 30883564 PMCID: PMC6422261 DOI: 10.1371/journal.pone.0207965] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 02/26/2019] [Indexed: 12/19/2022] Open
Abstract
PURPOSE The aim was to determine effects of diluent monomer and monocalcium phosphate monohydrate (MCPM) on polymerization kinetics and volumetric stability, apatite precipitation, strontium release and fatigue of novel dual-paste composites for vertebroplasty. MATERIALS AND METHODS Polypropylene (PPGDMA) or triethylene (TEGDMA) glycol dimethacrylates (25 wt%) diluents were combined with urethane dimethacrylate (70 wt%) and hydroxyethyl methacrylate (5 wt%). 70 wt% filler containing glass particles, glass fibers (20 wt%) and polylysine (5 wt%) was added. Benzoyl peroxide and MCPM (10 or 20 wt%) or N-tolyglycine glycidyl methacrylate and tristrontium phosphate (15 wt%) were included to give initiator or activator pastes. Commercial PMMA (Simplex) and bone composite (Cortoss) were used for comparison. ATR-FTIR was used to determine thermal activated polymerization kinetics of initiator pastes at 50-80°C. Paste stability, following storage at 4-37°C, was assessed visually or through mixed paste polymerization kinetics at 25°C. Polymerization shrinkage and heat generation were calculated from final monomer conversions. Subsequent expansion and surface apatite precipitation in simulated body fluid (SBF) were assessed gravimetrically and via SEM. Strontium release into water was assessed using ICP-MS. Biaxial flexural strength (BFS) and fatigue properties were determined at 37°C after 4 weeks in SBF. RESULTS Polymerization profiles all exhibited an inhibition time before polymerization as predicted by free radical polymerization mechanisms. Initiator paste inhibition times and maximum reaction rates were described well by Arrhenius plots. Plot extrapolation, however, underestimated lower temperature paste stability. Replacement of TEGDMA by PPGDMA, enhanced paste stability, final monomer conversion, water-sorption induced expansion and strontium release but reduced polymerization shrinkage and heat generation. Increasing MCPM level enhanced volume expansion, surface apatite precipitation and strontium release. Although the experimental composite flexural strengths were lower compared to those of commercially available Simplex, the extrapolated low load fatigue lives of all materials were comparable. CONCLUSIONS Increased inhibition times at high temperature give longer predicted shelf-life whilst stability of mixed paste inhibition times is important for consistent clinical application. Increased volumetric stability, strontium release and apatite formation should encourage bone integration. Replacing TEGDMA by PPGDMA and increasing MCPM could therefore increase suitability of the above novel bone composites for vertebroplasty. Long fatigue lives of the composites may also ensure long-term durability of the materials.
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Affiliation(s)
- Piyaphong Panpisut
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Muhammad Adnan Khan
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Kirsty Main
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Mayda Arshad
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Wendy Xia
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Haralampos Petridis
- Department of Restorative Dentistry, Unit of Prosthodontics, UCL Eastman Dental Institute, London, United Kingdom
| | - Anne Margaret Young
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
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Charlier Q, Fontanier JC, Lortie F, Pascault JP, Gerard JF. Rheokinetic study of acrylic reactive mixtures dedicated to fast processing of fiber-reinforced thermoplastic composites. J Appl Polym Sci 2018. [DOI: 10.1002/app.47391] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Quentin Charlier
- University of Lyon, INSA-Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223; F-69621 Villeurbanne France
| | - Jean-Charles Fontanier
- University of Lyon, INSA-Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223; F-69621 Villeurbanne France
| | - Frédéric Lortie
- University of Lyon, INSA-Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223; F-69621 Villeurbanne France
| | - Jean-Pierre Pascault
- University of Lyon, INSA-Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223; F-69621 Villeurbanne France
| | - Jean-François Gerard
- University of Lyon, INSA-Lyon, Ingénierie des Matériaux Polymères, UMR CNRS 5223; F-69621 Villeurbanne France
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Effect of Plasma Treatment and Its Post Process Duration on Shear Bonding Strength and Antibacterial Effect of Dental Zirconia. MATERIALS 2018; 11:ma11112233. [PMID: 30423984 PMCID: PMC6266075 DOI: 10.3390/ma11112233] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/06/2018] [Accepted: 11/07/2018] [Indexed: 01/11/2023]
Abstract
We have investigated the effect of non-thermal atmospheric pressure plasma (NTAPP) treatment and the post process time on the bonding strength and surface sterilization of dental zirconia. Presintered zirconia specimens were manufactured as discs, and then subjected to a 30-min argon treatment (Ar, 99.999%; 10 L/min) using an NTAPP device. Five post-treatment durations were evaluated: control (no treatment), P0 (immediate), P1 (24 h), P2 (48 h), and P3 (72 h). The surface characteristics, shear bonding strength (SBS) with two resin cements, and Streptococcus mutans biofilm formation of these plasma-treated dental zirconia were tested. Plasma did not change the roughness, and caused surface element changes and surface energy increase. Due to this increase in surface energy, SBS increased significantly (p < 0.05) within 48 h when RelyXTM U200 was used. However, the increase of surface oxygen significantly decreased (p < 0.05) the SBS of Panavia F 2.0 when using plasma immediately (P0). S. mutans adhesion decreased significantly (p < 0.05) for the P0, P1, and P2 groups compared to the control. The P0 group exhibited lower biofilm thickness than the other experimental groups due to the increased hydrophilicity (p < 0.05). Our study suggests that there is a suitable time window for the post NTAPP treatment regarding bonding strength and antimicrobial growth persist.
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Aromaa MK, Vallittu PK. Delayed post-curing stage and oxygen inhibition of free-radical polymerization of dimethacrylate resin. Dent Mater 2018; 34:1247-1252. [PMID: 30131114 DOI: 10.1016/j.dental.2018.06.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 04/20/2018] [Accepted: 06/07/2018] [Indexed: 11/29/2022]
Abstract
OBJECTIVE It is known that after light-initiated free radical polymerization of a dimethacrylate monomer system, the curing continues for some period of time after the curing light emission has stopped (so-called delayed post-curing stage, DPCS). It is also known that during free radical polymerization, the presence of oxygen effectively inhibits polymerization of monomers. However, less is known of the influence of oxygen inhibition of light initiated polymerization during the DPCS. The aim of this study was to determine some polymerization related properties of a resin system during the DPCS. METHODS Monomer systems of BisGMA-TEGDMA (60/40%) with light sensitive initiator-activator (camphorquinone-amine) system were polymerized by light-initiation (wavelength average 430-480nm) with a radiation intensity of 1200mW/mm2 for 20s on the ATR sensor of the fourier transform infrared (FTIR) spectrometer. After light curing, the samples were divided into two groups: the DPCS stage was allowed to continue in air (O2-exposed group) or the samples were protected from the direct effect of air (O2-protected group). The degree of monomer conversion (DC%) was monitored from the sample surface up to 360min from both groups of samples (n=6). Sample surfaces were additionally analyzed for surface microhardness (VHN) at four time-points corresponding to time-points of the DC% measurement (n=6). RESULTS After ending the light-curing of 20s, i.e. during the DPCS, the DC% still increased from 50% to 65% in the O2-protected group, whereas no increase was seen in the O2-exposed group. Surface microhardness increased from 2.99 to 9.10 VHN of the O2-protected samples and to 4.80 of the O2-exposed samples during a 6-h period. Surface microhardness differed significantly between the groups (p<0.005). There was significant correlation between the microhardness and DPCS (O2-protected r=0.950; O2-exposed r=0.940, p<0.001). A correlation was also found between degree of conversion values and DPCS time (O2-protected r=0.941; for O2-exposed r=0.780, p<0.001). SIGNIFICANCE The results of this study suggested that O2-inhibition of free radical polymerization of dimethacrylate resin occurred after ending the curing light emission. This correlated with a lower surface microhardness of the polymer when the DPCS continued under air-exposure.
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Affiliation(s)
- Mikke K Aromaa
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of Turku, Turku, Finland.
| | - Pekka K Vallittu
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of Turku, Turku, Finland; City of Turku, Division of Welfare, Finland
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Pongprueksa P, De Munck J, Inokoshi M, Van Meerbeek B. Polymerization efficiency affects interfacial fracture toughness of adhesives. Dent Mater 2018; 34:684-692. [DOI: 10.1016/j.dental.2018.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 01/15/2018] [Indexed: 11/12/2022]
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Lise DP, Van Ende A, De Munck J, Yoshihara K, Nagaoka N, Cardoso Vieira LC, Van Meerbeek B. Light irradiance through novel CAD–CAM block materials and degree of conversion of composite cements. Dent Mater 2018; 34:296-305. [DOI: 10.1016/j.dental.2017.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 10/20/2017] [Accepted: 11/09/2017] [Indexed: 11/25/2022]
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Phommalysack-Lovan J, Chu Y, Boyer C, Xu J. PET-RAFT polymerisation: towards green and precision polymer manufacturing. Chem Commun (Camb) 2018; 54:6591-6606. [DOI: 10.1039/c8cc02783h] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Photoinduced electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) process has opened up a new way of precision polymer manufacturing to satisfy the concept of green chemistry.
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Affiliation(s)
- Jamie Phommalysack-Lovan
- Centre for Advanced Macromolecular Design (CAMD) and Australian Centre for NanoMedicine (ACN)
- School of Chemical Engineering
- UNSW Sydney
- Australia
| | - Yingying Chu
- Centre for Advanced Macromolecular Design (CAMD) and Australian Centre for NanoMedicine (ACN)
- School of Chemical Engineering
- UNSW Sydney
- Australia
| | - Cyrille Boyer
- Centre for Advanced Macromolecular Design (CAMD) and Australian Centre for NanoMedicine (ACN)
- School of Chemical Engineering
- UNSW Sydney
- Australia
| | - Jiangtao Xu
- Centre for Advanced Macromolecular Design (CAMD) and Australian Centre for NanoMedicine (ACN)
- School of Chemical Engineering
- UNSW Sydney
- Australia
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Photo-calorimetry method optimization for the study of light-initiated radical polymerization of dental resins. POLYMER 2018. [DOI: 10.1016/j.polymer.2017.12.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Ferracane J, Hilton T, Stansbury J, Watts D, Silikas N, Ilie N, Heintze S, Cadenaro M, Hickel R. Academy of Dental Materials guidance—Resin composites: Part II—Technique sensitivity (handling, polymerization, dimensional changes). Dent Mater 2017; 33:1171-1191. [DOI: 10.1016/j.dental.2017.08.188] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 08/29/2017] [Indexed: 11/30/2022]
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Ouchi H, Tsujimoto A, Nojiri K, Hirai K, Takamizawa T, Barkmeier WW, Latta MA, Miyazaki M. Effect of Oxygen Inhibition Layer of Universal Adhesives on Enamel Bond Fatigue Durability and Interfacial Characteristics With Different Etching Modes. Oper Dent 2017; 42:636-645. [PMID: 28976848 DOI: 10.2341/16-255-l] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the effect of the oxygen inhibition layer of universal adhesive on enamel bond fatigue durability and interfacial characteristics with different etching modes. METHODS The three universal adhesives used were Scotchbond Universal Adhesive (3M ESPE, St Paul, MN, USA), Adhese Universal (Ivoclar Vivadent, Schaan, Lichtenstein), and G-Premio Bond (GC, Tokyo, Japan). The initial shear bond strength and shear fatigue strength to enamel was determined in the presence and absence of the oxygen inhibition layer, with and without phosphoric acid pre-etching. The water contact angle was also measured in all groups using the sessile drop method. RESULTS The enamel bonding specimens with an oxygen inhibition layer showed significantly higher (p<0.05) initial shear bond strengths and shear fatigue strengths than those without, regardless of the adhesive type and etching mode. Moreover, the water contact angles on the specimens with an oxygen inhibition layer were significantly lower (p<0.05) than on those without, regardless of etching mode. CONCLUSION The results of this study suggest that the oxygen inhibition layer of universal adhesives significantly increases the enamel bond fatigue durability and greatly changes interfacial characteristics, suggesting that the bond fatigue durability and interfacial characteristics of these adhesives strongly rely on its presence.
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de Lima E, Santos R, Durão M, Nascimento A, Braz R. Universal cements: dual activated and chemically activated. ACTA BIOMATERIALIA ODONTOLOGICA SCANDINAVICA 2017. [PMID: 28642922 PMCID: PMC5433229 DOI: 10.1080/23337931.2016.1221314] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Objective: The aim of the present study was to assess the bond strength of universal cements cured either dually or chemically only. Methods: Three cements were assessed using different types of application: dual activated (DA) or chemically activated (CA). In total 80 dentin blocks were used, obtained through the enamel wear of the lingual and buccal surfaces of bovine incisors. Standard cone-shaped cavity preparations were created using diamond burs. Subsequently, indirect restoration blocks were designed with Filtek Z350 (3M ESPE) composite resin. The teeth were divided into two groups (DA and CA) and then subdivided into four subgroups (n = 10) prior to cementation with the respective products: Duo-Link (Bisco); RelyX Ultimate (3M ESPE); Nexus 3 (Kerr) and conventional RelyX ARC (3M ESPE) as the control. The cementation in the PA group was applied following the manufacturer’s instructions. The CA group was cemented in a darkroom to avoid exposure to light. They were stored in distilled water at 37 °C for 24 h and submitted to the push-out test. Data were analyzed by two-way ANOVA and Tukey’s post-hoc test (p < .05). Results: The greatest bond strength results were obtained for photoactivated universal cements. Conclusion: Chemical activation is not sufficient to ensure acceptable bond strength.
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Affiliation(s)
| | | | - Márcia Durão
- University of PernambucoCamaragibe, RecifeBrazil
| | | | - Rodivan Braz
- University of PernambucoCamaragibe, RecifeBrazil
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Lee MJ, Kim MJ, Kwon JS, Lee SB, Kim KM. Cytotoxicity of Light-Cured Dental Materials according to Different Sample Preparation Methods. MATERIALS 2017; 10:ma10030288. [PMID: 28772647 PMCID: PMC5503327 DOI: 10.3390/ma10030288] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 03/06/2017] [Accepted: 03/09/2017] [Indexed: 11/16/2022]
Abstract
Dental light-cured resins can undergo different degrees of polymerization when applied in vivo. When polymerization is incomplete, toxic monomers may be released into the oral cavity. The present study assessed the cytotoxicity of different materials, using sample preparation methods that mirror clinical conditions. Composite and bonding resins were used and divided into four groups according to sample preparation method: uncured; directly cured samples, which were cured after being placed on solidified agar; post-cured samples were polymerized before being placed on agar; and “removed unreacted layer” samples had their oxygen-inhibition layer removed after polymerization. Cytotoxicity was evaluated using an agar diffusion test, MTT assay, and confocal microscopy. Uncured samples were the most cytotoxic, while removed unreacted layer samples were the least cytotoxic (p < 0.05). In the MTT assay, cell viability increased significantly in every group as the concentration of the extracts decreased (p < 0.05). Extracts from post-cured and removed unreacted layer samples of bonding resin were less toxic than post-cured and removed unreacted layer samples of composite resin. Removal of the oxygen-inhibition layer resulted in the lowest cytotoxicity. Clinicians should remove unreacted monomers on the resin surface immediately after restoring teeth with light-curing resin to improve the restoration biocompatibility.
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Affiliation(s)
- Myung-Jin Lee
- Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Korea.
- Brain Korea 21 PLUS Project, Yonsei University College of Dentistry, Seoul 03722, Korea.
| | - Mi-Joo Kim
- Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Korea.
| | - Jae-Sung Kwon
- Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Korea.
| | - Sang-Bae Lee
- Dental Device Testing and Evaluation Center, Yonsei University College of Dentistry, Seoul 03722, Korea.
| | - Kwang-Mahn Kim
- Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Korea.
- Brain Korea 21 PLUS Project, Yonsei University College of Dentistry, Seoul 03722, Korea.
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Price RBT, Labrie D, Rueggeberg FA, Sullivan B, Kostylev I, Fahey J. Correlation between the beam profile from a curing light and the microhardness of four resins. Dent Mater 2016; 30:1345-57. [PMID: 25460008 DOI: 10.1016/j.dental.2014.10.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 07/29/2014] [Accepted: 10/07/2014] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To demonstrate the effect of localized irradiance and spectral distribution inhomogeneities of one LED-based dental light-curing unit (LCU) on the corresponding microhardness values at the top, and bottom surfaces of four dental resin-based composites (RBCs), which contained either camphorquinone (CQ) alone or a combination of CQ and monoacylphosphine oxide (TPO) as photoinitiators. METHODS Localized irradiance beam profiles from a polywave LED-based LCU were recorded five times using a laser beam analyzer, without and with either a 400 nm or 460 nm narrow bandpass filter placed in front of the camera lens. Five specimens of each of the four RBCs (two containing CQ/TPO and two containing CQ-only) were exposed for 5-, 10-, or 30-s with the light guide directly on the top surface of the RBC. After 24 h, Knoop microhardness values were measured at 45 locations across the top and bottom surfaces of each specimen. Microhardness readings for each RBC surface and exposure time were correlated with localized patterns of the LCU beam profile, measured using the 400 nm and 460 nm bandpass filters. Spearman rank correlation was used to avoid relying on an assumption of a bivariate normal distribution for the KHN and irradiance. RESULTS The local irradiance and spectral emission values were not uniformly distributed across the light tip. There was a strong significant positive correlation with the irradiance beam profile values from the LCU taken through bandpass filters and the microhardness maps of the RBC surfaces exposed for 5 and 10 s. The strength of this correlation decreased with increasing exposure time for the RBCs containing CQ only, and increased for the RBCs containing both CQ and TPO. CONCLUSIONS Localized beam and spectral distributions across the tip end of the light guide strongly correlated with corresponding areas of microhardness in both the top and bottom surfaces among four RBCs with different photoinitiator contents. Significance: A light-curing unit with a highly inhomogeneous light output can adversely affect localized microhardness of resin-based composites and this may be a contributing factor for premature failure of a restoration.
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Affiliation(s)
- Richard B T Price
- Dental Clinical Sciences, Dalhousie University, Halifax, NS, Canada.
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Corrigan N, Rosli D, Jones JWJ, Xu J, Boyer C. Oxygen Tolerance in Living Radical Polymerization: Investigation of Mechanism and Implementation in Continuous Flow Polymerization. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01306] [Citation(s) in RCA: 151] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Nathaniel Corrigan
- Centre for Advanced Macromolecular Design (CAMD), School of Chemical
Engineering, and ‡Australian Centre for NanoMedicine, School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
| | - Dzulfadhli Rosli
- Centre for Advanced Macromolecular Design (CAMD), School of Chemical
Engineering, and ‡Australian Centre for NanoMedicine, School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
| | - Jesse Warren Jeffery Jones
- Centre for Advanced Macromolecular Design (CAMD), School of Chemical
Engineering, and ‡Australian Centre for NanoMedicine, School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
| | - Jiangtao Xu
- Centre for Advanced Macromolecular Design (CAMD), School of Chemical
Engineering, and ‡Australian Centre for NanoMedicine, School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
| | - Cyrille Boyer
- Centre for Advanced Macromolecular Design (CAMD), School of Chemical
Engineering, and ‡Australian Centre for NanoMedicine, School of Chemical Engineering, UNSW Australia, Sydney, NSW 2052, Australia
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Effect of curing light emission spectrum on the nanohardness and elastic modulus of two bulk-fill resin composites. Dent Mater 2016; 32:535-50. [DOI: 10.1016/j.dental.2015.12.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 12/21/2015] [Accepted: 12/21/2015] [Indexed: 02/01/2023]
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