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Lei YC, Zhou J, Zhou W, Wang Y, Zhang M, Zhang A, Wang L. Advanced development of anion-exchange membrane electrolyzers for hydrogen production: from anion-exchange membranes to membrane electrode assemblies. Chem Commun (Camb) 2024. [PMID: 39262314 DOI: 10.1039/d4cc03043e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2024]
Abstract
Anion-exchange membrane water electrolysis (AEMWE) has attracted attention owing to its operation in alkaline environments, which offers the advantage of not requiring the use of precious metals. Additionally, AEMWE exhibits higher kinetics in the hydrogen evolution reaction, enabling higher hydrogen production efficiency. The anion-exchange membrane (AEM) fabrication, catalyst design, and membrane electrode assembly (MEA) are crucial for enhancing the total water electrolysis performance. There is an urgent need to summarize the advances in the development of AEMWE to pave the way for the commercialization of AEMWE. In this review, first, the fundamental principles of AEMWE technology are introduced. Second, the optimization of AEM with high ion conductivity and high stability through innovative synthetic methods are discussed in detail. Third, the designs of catalysts to increase the reaction rates by regulating the OH-adsorption environment and relieving OH blockage are introduced. Last but not least, a systematic summary of the concepts of 3D-ordered MEA, 3D-unified MEA, and 3D-self-supported MEA is presented. This review would be helpful to enhance the overall performance of AEMWE and promote the development of green hydrogen energy.
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Affiliation(s)
- Yun Chao Lei
- College of Electronic and Optical Engineering, Institute of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
| | - Jiayang Zhou
- College of Electronic and Optical Engineering, Institute of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
| | - Wentao Zhou
- College of Electronic and Optical Engineering, Institute of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
| | - Yan Wang
- College of Electronic and Optical Engineering, Institute of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
| | - Mengyang Zhang
- College of Electronic and Optical Engineering, Institute of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
| | - Anlei Zhang
- College of Science, Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
| | - Longlu Wang
- College of Electronic and Optical Engineering, Institute of Flexible Electronics (Future Technology), Nanjing University of Posts & Telecommunications (NJUPT), Nanjing 210023, Jiangsu, P. R. China.
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Lee SY, Shimada Y, Sadr A, Tabata T, Sato T, Byun JE, Han SH. Degree of conversion and interfacial adaptation of touch-cure resin cement polymerized by self-curing or dual-curing with reduced light. Clin Oral Investig 2024; 28:463. [PMID: 39090476 DOI: 10.1007/s00784-024-05858-1] [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: 05/13/2024] [Accepted: 07/23/2024] [Indexed: 08/04/2024]
Abstract
OBJECTIVES The first aim of this study was to determine whether there is a difference in degree of conversion (DC) of touch-cure cements polymerized by self-curing with adhesive or dual-curing under reduced light. The second aim was to compare interfacial adaptation of zirconia restoration cemented using touch-cure cements self-cured or dual-cured by reduced light. METHODS The DC of touch-cure resin cements with adhesive was measured continuously using Fourier transform infrared spectrometry. Experimental groups differed depending on touch-cure cement. Each group had three subgroups of polymerization method. For subgroup 1, the DC was measured by self-curing. For subgroups 2 and 3, the DCs were measured by dual-curing with reduced light penetrating 3 mm and 1 mm zirconia blocks, respectively. For interfacial adaptation evaluation, Class I cavity was prepared on an extracted third molar, and zirconia restoration was fabricated. The restoration was cemented using the same cement. Groups and subgroups for interfacial adaptation were the same as those of the DC measurement. After thermo-cycling, interfacial adaptation at the tooth-restoration interface was evaluated using swept-source optical coherence tomography imaging. RESULTS The DC of touch-cure cement differed depending on the measurement time, resin cement, and polymerization method (p < 0.05). Interfacial adaptation was different depending on the resin cement and polymerization method (p < 0.05). CONCLUSION For touch-cure cement, light-curing with higher irradiance presented a higher DC and superior interfacial adaptation than light-curing with lower irradiance or self-curing. CLINICAL RELEVANCE Although some adhesives accelerate the self-curing of touch-cure cement, light-curing for touch-cure cement is necessary for zirconia cementation.
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Affiliation(s)
- Su Young Lee
- Department of Prosthodontics, Seoul St. Mary's Dental Hospital, College of Medicine, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul, 06591, Republic of Korea
| | - Yasushi Shimada
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Alireza Sadr
- Department of Restorative Dentistry, School of Dentistry, University of Washington, 1959 NE Pacific St, B162, Seattle, WA, 98195, USA
| | - Tomoko Tabata
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Takaaki Sato
- Department of Oral Biomedical Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Ji-Eun Byun
- Department of Conservative Dentistry, College of Dentistry, Yonsei University, #50 Yonsei-ro, Seodaemun-gu, Seoul, Korea
| | - Seung-Hoon Han
- Department of Conservative Dentistry, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon, Gyeonggi-do, 16247, South Korea.
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Alghanaim N, Kern M, Yazigi C, Chaar MS. Effects of sterilization, conditioning, and thermal aging on the retention of zirconia hybrid abutments: A laboratory study. Clin Implant Dent Relat Res 2024; 26:679-687. [PMID: 38680076 DOI: 10.1111/cid.13332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 04/05/2024] [Accepted: 04/08/2024] [Indexed: 05/01/2024]
Abstract
OBJECTIVE To investigate the effects of sterilization, conditioning method, and thermal aging on the retentive strength of two-piece zirconia abutments. MATERIALS AND METHODS In total, 128 stock zirconia abutments were divided into four groups (n = 32) according to the conditioning parameters: (A) air-abrasion using 50 μm alumina particles/1.0 bar, (B) 50 μm/2.0 bar, (C) 100 μm/1.0 bar, and (D) 100 μm/2.0 bar. All abutments were bonded onto titanium bases using DTK adhesive resin and stored in water bath (37°C) for 72 h. Each group was subdivided into two subgroups (n = 16), group 1 was disinfected, whereas group 2 followed disinfection and autoclave sterilization. Half of the specimens of each subgroup (n = 8) was directly subjected to the axial retention test (groups N), while the other half was first subjected to 150 days of thermocycling followed by retention test (groups T). Statistical analysis was performed with three-way ANOVA, additional statistical analysis was performed by using separate one-way ANOVAs followed by the Tukey's post-hoc test for post hoc pairwise comparisons among groups. RESULTS The highest median retention strength was recorded for group B2N (1390 N), whereas the lowest strength was recorded for group C1T (688 N). No significant interaction (p ≥ 0.05) was detected between the different variables; conditioning method, sterilization, and the thermal cycling regarding the effect on the resulting retention. However, the sterilization always showed a positive effect. Thermocycling presented an adversely significant effect only in the absence of sterilization (p < 0.05), with the exception of subgroups A. For the sterilized groups, thermocycling had no statistically significant effect on the retention. CONCLUSION Steam autoclaving increased the retention of hybrid zirconia abutments. DTK adhesive resin for two-piece zirconia abutments performed well after sterilization and thermocycling.
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Affiliation(s)
- Nalah Alghanaim
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany
- Department of Prosthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Matthias Kern
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany
| | - Christine Yazigi
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany
| | - M Sad Chaar
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany
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Marovic D, Bota M, Tarle F, Par M, Haugen HJ, Zheng K, Pavić D, Miloš M, Čižmek L, Babić S, Čož-Rakovac R, Trebše P, Boccaccini AR. The influence of copper-doped mesoporous bioactive nanospheres on the temperature rise during polymerization, polymer cross-linking density, monomer release and embryotoxicity of dental composites. Dent Mater 2024; 40:1078-1087. [PMID: 38797613 DOI: 10.1016/j.dental.2024.05.012] [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: 11/04/2023] [Revised: 03/05/2024] [Accepted: 05/13/2024] [Indexed: 05/29/2024]
Abstract
OBJECTIVES Composites with copper-doped mesoporous bioactive nanospheres (Cu-MBGN) were developed to prevent secondary caries by imparting antimicrobial and ion-releasing/remineralizing properties. METHODS Seven experimental composites containing 1, 5 or 10 wt% Cu-MBGN, the corresponding inert controls (silica) and bioactive controls (bioactive glass 45S5) were prepared. The temperature rise during light curing, cross-linking density by ethanol softening test, monomer elution and their potential adverse effects on the early development of zebrafish Danio rerio was investigated. RESULTS Materials combining Cu-MBGN and silica showed the highest resistance to ethanol softening, as did the bioactive controls. Cu-MBGN composites showed significant temperature rise and reached maximum temperature in the shortest time. Bisphenol A was not detected, while bis-GMA was found only in the control materials and TEGDMA in the eluates of all materials. There was no increase in zebrafish mortality and abnormality rates during exposure to the eluates of any of the materials. CONCLUSIONS The composite with 5 wt% Cu-MBGN combined with nanosilica fillers showed the lowest ethanol softening, indicating the polymer's highest durability and cross-linking density. Despite the TEGDMA released from all tested materials, no embryotoxic effect was observed.
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Affiliation(s)
- Danijela Marovic
- University of Zagreb School of Dental Medicine, Department of Endodontics and Restorative Dental Medicine, Gunduliceva 5, 10000 Zagreb, Croatia.
| | - Maria Bota
- student, University of Zagreb School of Dental Medicine, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Frano Tarle
- student, University of Zagreb School of Dental Medicine, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Matej Par
- University of Zagreb School of Dental Medicine, Department of Endodontics and Restorative Dental Medicine, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Håvard J Haugen
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, Geitmyrsveien 71, 0455 Oslo, Norway
| | - Kai Zheng
- Engineering Research Center of Stomatological Translational Medicine, Nanjing Medical University, 136 Hanzhong Rd., 210029 Nanjing, China; Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, Cauerstr. 6, 91058 Erlangen, Germany
| | | | | | - Lara Čižmek
- Ruđer Bošković Institute, Laboratory for Biotechnology in Aquaculture, Division of Materials Chemistry, Bijenička 54, Zagreb, Croatia
| | - Sanja Babić
- Ruđer Bošković Institute, Laboratory for Biotechnology in Aquaculture, Division of Materials Chemistry, Bijenička 54, Zagreb, Croatia
| | - Rozelindra Čož-Rakovac
- Ruđer Bošković Institute, Laboratory for Biotechnology in Aquaculture, Division of Materials Chemistry, Bijenička 54, Zagreb, Croatia
| | - Polonca Trebše
- Faculty of Health Sciences, University of Ljubljana, Zdravstvena pot 5, 1000 Ljubljana, Slovenia
| | - Aldo R Boccaccini
- Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, Cauerstr. 6, 91058 Erlangen, Germany
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Negovetic Mandic V, Plancak L, Marovic D, Tarle Z, Trutina Gavran M, Par M. Mechanical Properties of Alkasite Material with Different Curing Modes and Simulated Aging Conditions. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2777. [PMID: 38894041 PMCID: PMC11173928 DOI: 10.3390/ma17112777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/02/2024] [Accepted: 06/05/2024] [Indexed: 06/21/2024]
Abstract
This study aimed to evaluate the micro-mechanical and macro-mechanical properties of self-cured and light-cured alkasite and to investigate how accelerated degradation in acidic, alkaline, and ethanol solutions affects the macro-mechanical properties of self-cured and light-cured alkasite. The specimens of the alkasite material (Cention Forte, Ivoclar Vivadent) were prepared according to the following three curing modes: (1) light-cured immediately, (2) light-cured after a 5-min delay, and (3) self-cured. Microhardness was tested before and after immersion in absolute ethanol to indirectly determine crosslink density, while flexural strength and flexural modulus were measured using a three-point bending test after accelerated aging in the following solutions: (1) lactic acid solution (pH = 4.0), (2) NaOH solution (pH = 13.0), (3) phosphate-buffered saline solution (pH = 7.4), and (4) 75% ethanol solution. The data were statistically analyzed using a two-way ANOVA and Tukey post hoc test. The results showed that the microhardness, flexural strength, and flexural modulus were significantly lower in self-cured specimens compared to light-cured specimens. A 5-min delay between the extrusion of the material from the capsule and light curing had no significant effect on any of the measured properties. A significant effect of the accelerated aging solutions on macro-mechanical properties was observed, with ethanol and alkaline solutions having a particularly detrimental effect. In conclusion, light curing was preferable to self-curing, as it resulted in significantly better micro- and macro-mechanical properties, while a 5-min delay between mixing the capsule and light curing had no negative effects.
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Affiliation(s)
- Visnja Negovetic Mandic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (V.N.M.); (D.M.); (Z.T.)
| | - Laura Plancak
- 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; (V.N.M.); (D.M.); (Z.T.)
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (V.N.M.); (D.M.); (Z.T.)
| | - Milena Trutina Gavran
- Department of Morphology and Anthropology, Study of Dental Medicine, School of Medicine, University of Mostar, Zrinskog Frankopana 34, 88000 Mostar, Bosnia and Herzegovina;
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (V.N.M.); (D.M.); (Z.T.)
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Laforì A, Sailer I, Fehmer V, Mojon P, Burkhardt F, Pitta J. Influence of sterilization on the retention forces of lithium disilicate and polymer-infiltrated ceramic-network crowns bonded to titanium base abutments: An in-vitro study. Clin Oral Implants Res 2024; 35:377-385. [PMID: 38170349 DOI: 10.1111/clr.14234] [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: 07/25/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024]
Abstract
OBJECTIVES The aim of this study was to evaluate the effect of sterilization on the retention forces of lithium disilicate (LD) and polymer-infiltrated ceramic network (PICN) crowns bonded to titanium base (Ti-base) abutments. MATERIALS AND METHODS Forty LD and 40 PICN crowns were milled and then bonded to 80 Ti-bases with two resin composite cements: Multilink Hybrid Abutment (mh) and Panavia V5 (pv) for a total of 8 groups (n = 10). Half of the specimens (test) underwent an autoclaving protocol (pressure 1.1 bar, 121°C, 20.5 min) and the other half not (control). Restorations were screw-retained to implants, and retention forces (N) were measured with a pull-off testing machine. The surfaces of the Ti-bases and the crowns were inspected for the analysis of the integrity of the marginal bonding interface and failure mode. Student's t-test, chi-square test, and univariate linear regression model were performed to analyze the data (α = 0.05). RESULTS The mean pull-off retention forces ranged from 487.7 ± 73.4 N to 742.2 ± 150.3 N. Sterilized groups showed statistically significant overall higher maximum retention forces (p < .05), except for one combination (LD + mh). Sterilization led to an increased presence of marginal gaps and deformities compared to no-sterilization (p < .001), while no statistically significant relationship was found between failure mode and sterilization (p > .05). CONCLUSIONS Sterilization may have a beneficial effect on the retention forces of LD and PICN crowns bonded to titanium base abutments, although it may negatively influence the integrity of the marginal bonding interface.
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Affiliation(s)
- Andreina Laforì
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Irena Sailer
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Vincent Fehmer
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Philippe Mojon
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Felix Burkhardt
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - João Pitta
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
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Zancopé K, Borges G, Ribeiro M, Miranda RR, Peres TS, Soares CJ. Influence of Mono- and Multiwave Light-curing Units on the Microhardness and Degree of Conversion of Light-cured Resin Cements. Oper Dent 2023; 48:711-719. [PMID: 37881034 DOI: 10.2341/23-039-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2023] [Indexed: 10/27/2023]
Abstract
OBJECTIVES This study evaluated the Knoop hardness (KH, N/mm2) and degree of conversion (DC, %) on the margins of light-cured resin cements with different photoinitiators using a single light-curing unit (LCU) with two heads (mono- and multiwave). METHODS AND MATERIALS Three types of resin cements were used with different photoinitiators: Megalink Esthetic (Odontomega, São Paulo, Brazil) with a camphorquinone photoinitiator; Allcem Veneer (FGM, Joinville, Brazil) with the Advanced Polymerization system (APS), and Variolink Esthetic LC (Ivoclar Vivadent, Schaan, Liechtenstein). Thirty samples were collected and divided into six groups (n=5 each). The resin cement samples were made into the shape of a maxillary right central incisor and photoactivated under a 0.5-mm-thick ceramic sheet. A single LCU (Radii Xpert, SDI) with two heads (mono- and multiwave) was used. The tip of the LCU was positioned at the center of the sample in a standardized manner. Raman spectroscopy was performed to evaluate the DC, and KH was evaluated through the Knoop microhardness test. Five regions were evaluated: cervical, mesial, buccal (center), distal, and incisal. RESULTS There was a significant difference in the DC only for the type of cement (p<0.001), indicating that the cement with the APS photoinitiator presented excellent results. There were significant differences in the type of cement (p<0.001), type of light (p<0.001), region (p<0.001), and the interaction between the type of cement and type of light (p<0.001). The resin cement with the APS photoinitiator cured with monowave light showed the highest KH values. The beam profiles of all groups, with and without the interposition of ceramic and resin cement, were examined by light transmission. CONCLUSIONS The cement with the APS photoinitiator presented the best results with respect to the DC and KH. In comparison with mono- and multiwaves, the LCU may not be a determining factor for the properties of light-cured resin cements. The buccal region showed the best results for DC and KH, indicating the need for a greater amount of light-curing at the cementation margins.
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Affiliation(s)
- K Zancopé
- *Karla Zancopé, DDS, MSc, PhD, professor, Department of Occlusion, Fixed Prosthesis and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - Gcs Borges
- Giovanna C S Borges, DDS, MS, Department of Occlusion, Fixed Prosthesis and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - Mth Ribeiro
- Maria Tereza H Ribeiro, DDS, MS, PhD student, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - R R Miranda
- Rafael R Miranda, DDS, MS, PhD, professor, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - T S Peres
- Thiago S Peres, DDS, MS, PhD student, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - C J Soares
- Carlos J Soares, DDS, MS, PhD, professor and chair, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
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Mamba’udin A, Handayani M, Triawan F, Rahmayanti YD, Muflikhun MA. Excellent Characteristics of Environmentally Friendly 3D-Printed Nasopharyngeal Swabs for Medical Sample Collection. Polymers (Basel) 2023; 15:3363. [PMID: 37631419 PMCID: PMC10459119 DOI: 10.3390/polym15163363] [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: 07/03/2023] [Revised: 07/28/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
3D-printed nasopharyngeal swabs for medical sample collection have been manufactured via additive manufacturing (AM), evaluated, and characterized in the present study. A multi-part component of nasopharyngeal swabs was proposed, in which the swab and handle were manufactured separately to reach sustainable production and environmentally friendly products. The swab was investigated using tensile, flexural, surface roughness, dimensional accuracy, and sample collection testing. The influence of printing parameters and post-curing time treatment on the mechanical properties, surface roughness, and dimensional accuracy of 3D-printed nasopharyngeal swabs were also evaluated. The result showed that 3D-printed nasopharyngeal swab shows outstanding tensile strength compared to the commercial flock nasopharyngeal swab. Moreover, the swab neck flexibility test showed that both PLA and dental non-castable 3D-printed nasopharyngeal swabs were able to bend 180°. Subsequently, the surface roughness of 3D-printed nasopharyngeal swab was identic with the commercial flock nasopharyngeal swab. The proposed 3D-printed nasopharyngeal swab design could carry an artificial mucus sample of 141.6 mg at a viscosity of 9455.4 mPa.s. The cost to fabricate a 3D-printed nasopharyngeal swab was estimated at USD0.01-0.02 per swab. 3D-printed nasopharyngeal swab shows potential as a feasible option, greener, less medical waste, and more sustainable.
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Affiliation(s)
- Ahmad Mamba’udin
- Mechanical and Industrial Engineering Department, Gadjah Mada University, Jl. Grafika No.2, Yogyakarta 55281, Indonesia
| | - Murni Handayani
- Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), Puspiptek Area, Tangerang Selatan 15314, Indonesia
| | - Farid Triawan
- Department of Mechanical Engineering, Sampoerna University, Jl. Raya Pasar Minggu No.Kav. 16, Kec. Pancoran, Jakarta 12780, Indonesia
| | - Yosephin Dewiani Rahmayanti
- Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), Puspiptek Area, Tangerang Selatan 15314, Indonesia
| | - Muhammad Akhsin Muflikhun
- Mechanical and Industrial Engineering Department, Gadjah Mada University, Jl. Grafika No.2, Yogyakarta 55281, Indonesia
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Torno V, Soares P. Tribological behavior and wear mechanisms of dental resin composites with different polymeric matrices. J Mech Behav Biomed Mater 2023; 144:105962. [PMID: 37393888 DOI: 10.1016/j.jmbbm.2023.105962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/04/2023] [Accepted: 06/06/2023] [Indexed: 07/04/2023]
Abstract
The aim of this study was to investigate the effect of different polymeric matrices and their crosslink density on the mechanical and tribological properties of three commercially available dental resin composites, including Filtek Z250XT, Charisma Classic, and Venus Diamond One. The mechanical properties of the composites were investigated by instrumented indentation. The results showed that the polymeric matrix composition has a significant effect on the hardness and elastic modulus of the resins. Wear resistance was investigated by reciprocating ball-on-plane tests in artificial saliva. Results show that the TCD-based resin composite has higher crosslinking density resulting in a more wear-resistant material. There was also a strong correlation between wear resistance and the mechanical properties of the resin composites when comparing similar fillers. These findings suggest that the wear resistance of resin composites can be improved by increasing their crosslinking density and enhancing their mechanical properties. The study provides insights into the design and development of more wear-resistant resin composites for dental applications.
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Affiliation(s)
- Vladja Torno
- Mechanical Engineering, Polytechnic School, Pontificia Universidade Católica do Paraná, Curitiba - Brazil.
| | - Paulo Soares
- Mechanical Engineering, Polytechnic School, Pontificia Universidade Católica do Paraná, Curitiba - Brazil.
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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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11
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Han SH, Shimada Y, Sadr A, Tagami J, Tabata T, Nakagawa H, Yang SE. Effects of Material Thickness and Pretreatment on the Interfacial Gap of Translucent Zirconia Restorations with Self-adhesive Resin Cement. Oper Dent 2022; 47:535-548. [DOI: 10.2341/21-024-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2021] [Indexed: 11/07/2022]
Abstract
SUMMARY
Purpose
The first objective was to determine if the dual-curing of self-adhesive resin cement (SAC) with reduced light penetrating through zirconia had an effect on interfacial gap of zirconia restorations. The second purpose was to examine whether pretreatment methods for universal adhesive affected interfacial gap. The last aim was to compare the microhardness of SAC polymerized under different zirconia thicknesses.
Methods and Materials
This study evaluated self-adhesive resin cement (RelyX U200, 3M ESPE) after different pretreatment with universal adhesive (Single Bond Universal, 3M ESPE) under different polymerization conditions. CAD/CAM inlay cavities were prepared on extracted third molars. Translucent zirconia restorations were milled using Katana UTML (Kuraray). The teeth were divided into three groups: Groups I, II, and III in which the restoration thicknesses were 1, 2, and 3 mm. Each Group had three subgroups according to different pretreatment methods. For subgroup-1, no pretreatment was done on the prepared cavity. For subgroup-2, universal adhesive was applied and light-cured before cement placement (precure method). For subgroup-3, universal adhesive was applied; however, light-curing was done after cement placement (cocure method). After thermo-cycling, the interfacial gap at the restoration-tooth interface was investigated using swept-source optical coherence tomography imaging. Finally, microhardness was measured for SAC under different zirconia thicknesses. For statistical analysis, the interfacial gap was analyzed using two-way analysis of variance (ANOVA) to test the effect of cavity depth and pretreatment. In terms of each cavity depth and pretreatment, the interfacial gap was compared using one-way ANOVA and Scheffe’s test. One-way ANOVA was also performed for comparison of the Vickers hardness results.
Results
Different thicknesses of the restoration resulted in differences in interfacial gaps except between the precure method of Groups I and II (p<0.05). The effect of universal adhesive pretreatment was different depending on the restoration thickness with exceptions in Groups I and III (p<0.05). Vickers hardness number decreased as the low radiant exposure of light was applied (p<0.05).
Conclusion
Interfacial gap of zirconia restorations can differ depending on the material thickness, pretreatment, and activation mode. Reduced light intensity penetrating through zirconia may lead to higher interfacial gap percentage and lower microhardness of the self-adhesive resin cement. Application of a universal adhesive showed similar or reduced interfacial gaps in the cement space.
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Affiliation(s)
- S-H Han
- Seung-Hoon Han, DDS, PhD, assistant professor, Department of Conservative Dentistry, St Vincent Hospital, College of Medicine, The Catholic University of Korea
| | - Y Shimada
- Yasushi Shimada, DDS, PhD, professor, Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - A Sadr
- Alireza Sadr, DDS, PhD, associate professor, Department of Restorative Dentistry, School of Dentistry, University of Washington
| | - J Tagami
- Junji Tagami, DDS, PhD, professor emeritus, Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - T Tabata
- Tomoko Tabata, DDS, PhD, assistant professor, Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - H Nakagawa
- Hisaichi Nakagawa, DDS, PhD, assistant professor, Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - S-E Yang
- *Sung-Eun Yang, DDS, PhD, professor, Department of Conservative Dentistry, Seoul St Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
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12
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Hao Y, Qu S, Xiao Y, Sui Z, Han S, Zhu D, Wang C, Bian H. Study on the ozonation-modified multi-walled carbon nanotubes in polymer composites. Polym Bull (Berl) 2022. [DOI: 10.1007/s00289-022-04367-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Stiles A, Tison TA, Pruitt L, Vaidya U. Photoinitiator Selection and Concentration in Photopolymer Formulations towards Large-Format Additive Manufacturing. Polymers (Basel) 2022; 14:2708. [PMID: 35808752 PMCID: PMC9268840 DOI: 10.3390/polym14132708] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/27/2022] [Accepted: 06/27/2022] [Indexed: 02/04/2023] Open
Abstract
Photopolymers are an attractive option for large-format additive manufacturing (LFAM), because they can be formulated from structural thermosets and cure rapidly in ambient conditions under low-energy ultraviolet light-emitting diode (UV LED) lamps. Photopolymer cure is strongly influenced by the depth penetration of UV light, which can be limited in the 2-4 mm layer thicknesses typical of LFAM. Photoinitiator (PI) systems that exhibit photobleaching have proven useful in thick-section cure applications, because they generate a photoinitiation wavefront, but this effect is time-dependent. This study investigates the light transmission and through-thickness cure behavior in (meth)acrylate photopolymer formulations with the photobleaching initiator bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (BAPO). Utilizing an optical model developed by Kenning et al., lower concentrations (0.1 wt% to 0.5 wt%) of BAPO were predicted to yield rapid onset of photoinitiation. In situ cure measurements under continuous UV LED irradiation of 380 mW/cm2 showed that a 0.1 wt% concentration of BAPO achieved peak polymerization rate within 2.5 s at a 3-mm depth. With only 1 s of irradiation at 1.7 W/cm2 intensity, the 0.1 wt% BAPO formulation also achieved the highest level of cure of the formulas tested. For an irradiation dose of 5.5 J/cm2 at a duration of 3.7 s, cured polymer specimens achieved a flexural strength of 108 MPa and a flexural modulus of 3.1 GPa. This study demonstrates the utility of optical modeling as a potential screening tool for new photopolymer formulations, primarily in identifying an upper limit to PI concentration for the desired cure depth. The results also show that photobleaching provides only a limited benefit for LFAM applications with short (1.0 s to 3.7 s) UV irradiation times and indicate that excess PI concentration can inhibit light transmission even under extended irradiation times up to 60 s.
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Affiliation(s)
- Alex Stiles
- Bredesen Center for Interdisciplinary Research, University of Tennessee, Middle Drive, Knoxville, TN 37996, USA;
| | - Thomas-Allan Tison
- Tickle College of Engineering, University of Tennessee, Middle Drive, Knoxville, TN 37996, USA;
| | - Liam Pruitt
- Haslam College of Business, University of Tennessee, 1000 Volunteer Boulevard, Knoxville, TN 37996, USA;
| | - Uday Vaidya
- Tickle College of Engineering, University of Tennessee, Middle Drive, Knoxville, TN 37996, USA;
- Manufacturing Sciences Division, Oak Ridge National Laboratory, 2350 Cherahala Blvd, Knoxville, TN 37932, USA
- Institute for Advanced Composites Manufacturing Innovation, 2360 Cherahala Blvd, Knoxville, TN 37932, USA
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14
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Kumar D, Bolskar RD, Mutreja I, Jones RS. Methacrylate Polymers With “Flipped External” Ester Groups: A Review. FRONTIERS IN DENTAL MEDICINE 2022. [DOI: 10.3389/fdmed.2022.923780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Current resin composites have favorable handling and upon polymerization initial physical properties that allow for efficient material replacement of removed carious tooth structure. Dental resin composites have long term durability limitations due to the hydrolysis of ester bonds within the methacrylate based polymer matrix. This article outlines the importance of ester bonds positioned internal to the carbon-carbon double bond in current methacrylate monomers. Water and promiscuous salivary/bacterial esterase activity can initiate ester bond hydrolysis that can sever the polymer backbone throughout the material. Recent studies have custom synthesized, with the latest advances in modern organic chemical synthesis, a novel molecule named ethylene glycol bis (ethyl methacrylate) (EGEMA). EGEMA was designed to retain the reactive acrylate units. Upon intermolecular polymerization of vinyl groups, EGEMA ester groups are positioned outside the backbone of the polymer chain. This review highlights investigation into the degradation resistance of EGEMA using buffer, esterase, and microbial storage assays. Material samples of EGEMA had superior final physical and mechanical properties than traditional ethylene glycol dimethacrylate (EGDMA) in all degradation assays. Integrating bioinformatics-based biodegradation predictions to the experimental results of storage media analyzed by LC/GC-MS revealed that hydrolysis of EGEMA generated small amounts of ethanol while preserving the strength bearing polymer backbone. Prior studies support investigation into additional custom synthesized methacrylate polymers with “flipped external” ester groups. The long term goal is to improve clinical durability compared to current methacrylates while retaining inherent advantages of acrylic based chemistry, which may ease implementation of these novel methacrylates into clinical practice.
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15
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Marovic D, Par M, Posavec K, Marić I, Štajdohar D, Muradbegović A, Tauböck TT, Attin T, Tarle Z. Long-Term Assessment of Contemporary Ion-Releasing Restorative Dental Materials. MATERIALS (BASEL, SWITZERLAND) 2022; 15:4042. [PMID: 35744101 PMCID: PMC9227571 DOI: 10.3390/ma15124042] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 02/05/2023]
Abstract
The objective was to evaluate new commercially available ion-releasing restorative materials and compare them to established anti-cariogenic materials. Four materials were tested: alkasite Cention (Ivoclar Vivadent) in self-cure or light-cure mode, giomer Beautifil II (Shofu), conventional glass-ionomer Fuji IX (GC), and resin composite Tetric EvoCeram (Ivoclar Vivadent) as a control. Flexural strength, flexural modulus, and Weibull modulus were measured one day, three months, and after three months with accelerated aging in ethanol. Water sorption and solubility were evaluated for up to one year. Degree of conversion was measured during 120 min for self-cured and light-cured Cention. In this study, Beautifil II was the ion-releasing material with the highest flexural strength and modulus and with the best resistance to aging. Alkasite Cention showed superior mechanical properties to Fuji IX. Weibull analysis showed that the glass-ionomer had the least reliable distribution of mechanical properties with the highest water sorption. The solubility of self-cured alkasite exceeded the permissible values according to ISO 4049. Degree of conversion of light-cured Cention was higher than in self-cure mode. The use of alkasite Cention is recommended only in the light-cure mode.
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Affiliation(s)
- Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (D.M.); (D.Š.); (Z.T.)
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (D.M.); (D.Š.); (Z.T.)
| | - Karlo Posavec
- Private Dental Practice, Dr. Ivana Novaka 28, 40000 Čakovec, Croatia;
| | - Ivana Marić
- Private Dental Practice, Odranska 10, 10000 Zagreb, Croatia;
| | - Dominik Štajdohar
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (D.M.); (D.Š.); (Z.T.)
| | - Alen Muradbegović
- Private Dental Practice, Malkočeva 3, 75000 Tuzla, Bosnia and Herzegovina;
| | - Tobias T. Tauböck
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Plattenstrasse 11, 8032 Zurich, Switzerland; (T.T.T.); (T.A.)
| | - Thomas Attin
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Plattenstrasse 11, 8032 Zurich, Switzerland; (T.T.T.); (T.A.)
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia; (D.M.); (D.Š.); (Z.T.)
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16
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Mechanical characterization and adhesive properties of a dental adhesive modified with a polymer antibiotic conjugate. J Mech Behav Biomed Mater 2022; 129:105153. [DOI: 10.1016/j.jmbbm.2022.105153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 01/05/2022] [Accepted: 02/27/2022] [Indexed: 11/22/2022]
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17
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The Effect of Different Light Curing units and Tip Distances on Translucency Parameters of Bulk Fill Materials. Saudi Dent J 2022; 34:362-368. [PMID: 35814845 PMCID: PMC9264138 DOI: 10.1016/j.sdentj.2022.04.002] [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] [Received: 06/26/2021] [Revised: 03/31/2022] [Accepted: 04/06/2022] [Indexed: 11/29/2022] Open
Abstract
Objectives To evaluate the effect of light curing unit (LCU) types and distance from light curing unit tip on the translucency parameters (TP) of bulk fill composite materials. Materials and Methods Two bulk-fill resin composites and one nanohybrid composite were used in this study. The specimens were divided into groups based on the type of curing unit used, and further subdivided based on the distance of the curing source to the surface of the resin composite. Translucency was evaluated at 4 mm thickness (for the bulk-fill) and 2 mm thickness (for nanohybrid) after curing using two different light curing units at zero, 2 mm, and 4 mm distance. The results were analyzed using two-way ANOVA at the significance level of a p-value of < 0.05. Results Among all the tested materials, Filtek Bulk Fill Posterior RBC showed the highest TP at 0 mm distance when cured with Blue phase G2 LED LCU and it was the least affected by the differences in distances. However, Filtek Z350 nanohybrid composite had no significant differences between the three distances when cured with Blue phase G2 LCU. Conclusion Translucency values among the studied bulk-fill materials are affected by material composition, curing units and the distance of the tip of the light source to the restoration surface.
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Crystalline properties and morphology of bulk-fill dental resin composites as function of light-cure protocol and composition. Polym Bull (Berl) 2022. [DOI: 10.1007/s00289-022-04163-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Marovic D, Par M, Macan M, Klarić N, Plazonić I, Tarle Z. Aging-Dependent Changes in Mechanical Properties of the New Generation of Bulk-Fill Composites. MATERIALS 2022; 15:ma15030902. [PMID: 35160848 PMCID: PMC8839328 DOI: 10.3390/ma15030902] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/18/2022] [Accepted: 01/21/2022] [Indexed: 11/19/2022]
Abstract
This study evaluated the behavior of a new generation of bulk-fill resin composites after prolonged exposure to an aqueous environment and accelerated aging in ethanol. Six bulk-fill materials were tested (Tetric PowerFill, Filtek One Bulk Fill Restorative, Tetric EvoCeram Bulk Fill, Fill-Up!, Tetric PowerFlow, SDR Plus Bulk Fill Flowable) and compared to two conventional reference materials (Tetric EvoCeram and Tetric EvoFlow). Flexural strength, modulus, and Weibull parameters were examined at three time points: 1 day, 30 days, and 30 days followed by ethanol immersion. Degree of conversion after 30 days, water sorption, and solubility up to 90 days were also investigated. Filtek One Bulk Fill had the highest flexural strength and modulus among the tested materials, followed by Tetric PowerFill and SDR plus. Flexural strength and modulus of high-viscosity bulk-fill materials showed higher stability after accelerated aging in ethanol compared to their low-viscosity counterparts and reference materials. After 30 days, the degree of conversion was above 80% for all tested materials. Dual-cure material Fill-Up! was the best-cured material. The water sorption was highest for Fill-Up!, Filtek One Bulk Fill Restorative, and Tetric EvoFlow, while solubility was highest for Tetric EvoCeram. After aging in water and ethanol, new generation high-viscosity bulk-fill materials showed better mechanical properties than low-viscosity bulk-fill and conventional composites under extended light curing conditions.
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Affiliation(s)
- Danijela Marovic
- Department of Endodontics and Restorative Dental Medicine, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.M.); (I.P.); (Z.T.)
- Correspondence: (D.M.); (M.P.); Tel.: +385-1489-9203 (M.P.)
| | - Matej Par
- Department of Endodontics and Restorative Dental Medicine, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.M.); (I.P.); (Z.T.)
- Correspondence: (D.M.); (M.P.); Tel.: +385-1489-9203 (M.P.)
| | - Matea Macan
- Private Dental Practice, 10000 Zagreb, Croatia;
| | | | | | - Zrinka Tarle
- Department of Endodontics and Restorative Dental Medicine, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.M.); (I.P.); (Z.T.)
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Aldhafyan M, Silikas N, Watts DC. Influence of curing modes on thermal stability, hardness development and network integrity of dual-cure resin cements. Dent Mater 2021; 37:1854-1864. [PMID: 34593244 DOI: 10.1016/j.dental.2021.09.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/20/2021] [Accepted: 09/20/2021] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To explore the effect of different curing modes of conventional and self-adhesive dual-cure resin cements on their rates of thermal decomposition, hardness development and network integrity. METHODS Five self-adhesive (PANAVIA SA, RelyX Universal Resin, RelyX Unicem 2, Bifix SE and SpeedCEM Plus) and three conventional (PANAVIA V5, Nexus Third Generation and RelyX Ultimate Universal) dual-cure resin cements were investigated. Thermal decomposition stages, initial onset temperatures, the maximum rate of mass-loss and the filler mass-fraction of each resin cement were analysed by thermogravimetric analysis (TGA). Surface hardness was measured at 1h post-cure and after 24h of dry storage at 37°C. The relative network integrities were estimated from reductions in hardness after 168h of water storage. Data were analysed via one-way ANOVA, Tukey post-hoc tests and paired/independent sample t-tests (a=0.05). RESULTS No difference was apparent between TGA data for self-cured and light-cured specimens. Numerical differentiation of mass-loss versus temperature showed either single or multiple peaks. For the set of 8 cements, the maximum rate of mass-loss (%/°C) correlated negatively with residual mass at 600°C. All dry-stored cements increased in hardness from 1 to 24h, ranging from 20.4% to 52.6% for light-cure mode and from 41.3% to 112.6% for self-cure. After 168h water storage, the hardness of cements decreased: by 18.5%-36.2% for light-cured and by 9.8%-17.9% for self-cured. Overall, surface hardness was greater for light-cured cements. The initial onset temperature (IOT) of thermal decomposition correlated negatively with the hardness decrease produced by water-storage: r2=0.77 for light-cure and r2=0.88 for self-cure. This provided the basis for a relative scale of composite network integrity, probably reflecting differences in cross-link density. SIGNIFICANCE Light-curing, where possible, remains beneficial to the hardness and related properties of dual-cure resin cements. Combination of TG analysis and solvent softening experiments give an indication of relative network integrity - between materials - and their relative cross-link densities.
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Affiliation(s)
- Mohammed Aldhafyan
- Biomaterials Science, Division of Dentistry, School of Medical Sciences, University of Manchester, UK; Division of Dental Biomaterials Science, College of Dentistry, King Saud University, Saudi Arabia
| | - Nikolaos Silikas
- Biomaterials Science, Division of Dentistry, School of Medical Sciences, University of Manchester, UK.
| | - David C Watts
- Biomaterials Science, Division of Dentistry, School of Medical Sciences, University of Manchester, UK; Photon Science Institute, University of Manchester, UK.
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21
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de Maria VPK, de Paiva FFG, Cabrera FC, Hiranobe CT, Ribeiro GD, Paim LL, Job AE, dos Santos RJ. Mechanical and rheological properties of partial replacement of carbon black by treated ultrafine calcium carbonate in natural rubber compounds. Polym Bull (Berl) 2021. [DOI: 10.1007/s00289-021-03891-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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22
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Pérez-Mondragón AA, Cuevas-Suárez CE, García-Serrano J, Trejo-Carbajal N, Lobo-Guerrero A, Herrera-González AM. Adhesive Resins with High Shelf-Life Stability Based on Tetra Unsaturated Monomers with Tertiary Amines Moieties. Polymers (Basel) 2021; 13:polym13121944. [PMID: 34208102 PMCID: PMC8230799 DOI: 10.3390/polym13121944] [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: 05/26/2021] [Revised: 06/04/2021] [Accepted: 06/09/2021] [Indexed: 11/16/2022] Open
Abstract
This work reports the use of two monomers with two tertiary amines and four methacrylic (TTME) or acrylic (TTAC) terminal groups as co-initiators in the formulation of experimental resin adhesive systems. Both monomers were characterized by FT-IR and 1H NMR spectroscopies. The control adhesive was formulated with BisGMA, TEGDMA, HEMA, and the binary system CQ-EDAB as a photo-initiator system. For the experimental adhesives, the EDAB was completely replaced for the TTME or the TTAC monomers. The adhesives formulated with TTME or TTAC monomers achieved double bond conversion values close to 75%. Regarding the polymerization rate, materials formulated with TTME or TTAC achieved lower values than the material formulated with EDAB, giving them high shelf-life stability. The degree of conversion after shelf simulation was only reduced for the EDAB material. Ultimate tensile strength, translucency parameter, and micro-tensile bond strength to dentin were similar for control and experimental adhesive resins. Due to their characteristics, TTME and TTAC monomers are potentially useful in the formulation of photopolymerizable resins for dental use with high shelf-life stability.
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Affiliation(s)
- Alma Antonia Pérez-Mondragón
- Doctorado en Ciencias de los Materiales, Universidad Autónoma del Estado de Hidalgo, Pachuca-Tulancingo Km. 4.5, Carboneras, Mineral de la Reforma 42184, Hgo., Mexico;
- Laboratorio de Polímeros, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca-Tulancingo Km. 4.5, Carboneras, Mineral de la Reforma 42184, Hgo., Mexico; (J.G.-S.); (N.T.-C.); (A.L.-G.)
| | - Carlos Enrique Cuevas-Suárez
- Laboratorio de Biomateriales Dentales, Área Académica de Odontología, Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Circuito Ex Hacienda La Concepción S/N, San Agustín Tlaxiaca 42160, Hgo., Mexico
- Correspondence: (C.E.C.-S.); (A.M.H.-G.); Tel.: +52-771-717-2000 (C.E.C.-S.); +52-771-717-2000 (ext. 2281) (A.M.H.-G.)
| | - Jesús García-Serrano
- Laboratorio de Polímeros, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca-Tulancingo Km. 4.5, Carboneras, Mineral de la Reforma 42184, Hgo., Mexico; (J.G.-S.); (N.T.-C.); (A.L.-G.)
| | - Nayely Trejo-Carbajal
- Laboratorio de Polímeros, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca-Tulancingo Km. 4.5, Carboneras, Mineral de la Reforma 42184, Hgo., Mexico; (J.G.-S.); (N.T.-C.); (A.L.-G.)
| | - A. Lobo-Guerrero
- Laboratorio de Polímeros, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca-Tulancingo Km. 4.5, Carboneras, Mineral de la Reforma 42184, Hgo., Mexico; (J.G.-S.); (N.T.-C.); (A.L.-G.)
| | - Ana M. Herrera-González
- Laboratorio de Polímeros, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca-Tulancingo Km. 4.5, Carboneras, Mineral de la Reforma 42184, Hgo., Mexico; (J.G.-S.); (N.T.-C.); (A.L.-G.)
- Correspondence: (C.E.C.-S.); (A.M.H.-G.); Tel.: +52-771-717-2000 (C.E.C.-S.); +52-771-717-2000 (ext. 2281) (A.M.H.-G.)
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de Oliveira E, Zancanaro de Figueiredo E, Spohr AM, Lima Grossi M. Properties of Acrylic Resin For CAD/CAM: A Systematic Review and Meta-Analysis of In Vitro Studies. J Prosthodont 2021; 30:656-664. [PMID: 34036676 DOI: 10.1111/jopr.13394] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2021] [Indexed: 12/01/2022] Open
Abstract
PURPOSE This systematic review and meta-analysis of in vitro studies compared the prepolymerized acrylic resin used for CAD/CAM complete denture manufacturing versus the heat-polymerized acrylic resin for conventional complete dentures in terms of surface roughness, wettability, hardness and flexural strength. MATERIALS AND METHODS An electronic search was performed in the PubMed, Embase, LILACS and Web of Science databases, without language or date restrictions. Gray literature and manual search tools were also used. The systematic review was carried out by two researchers independently, following the inclusion criteria: in vitro studies testing the CAD/CAM acrylic resin with a control group of heat-polymerized acrylic resin which compared at least one of the four material properties above. The meta-analysis was performed separately for each property, using a random effect model. RESULTS Of the 914 studies found by means of search strategies, 698 were selected for the systematic review. After applying the eligibility criteria, only 17 articles were selected for the qualitative analysis in the systematic review; among these, 14 were included in the quantitative meta-analysis. The CAD/CAM prepolymerized acrylic resin in blocks had similar properties when compared to heat-polymerized acrylic resin in almost all outcome measures, with the exception of a statistically significant reduction in surface roughness. CONCLUSIONS Based on the findings of this systematic review and meta-analysis, equally satisfactory results can be expected from dental prosthesis manufactured by the CAD/CAM system when compared to conventional ones, with the additional potential of reducing the pigmentation and attached microorganisms due to the reduced surface roughness of the prepolymerized resin.
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Affiliation(s)
- Emanuele de Oliveira
- Post-Graduate Program in Dentistry (Prosthodontics), School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Elisa Zancanaro de Figueiredo
- Post-Graduate Program in Dentistry (Prosthodontics), School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Ana Maria Spohr
- Post-Graduate Program in Dentistry (Restorative Dentistry), School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Márcio Lima Grossi
- Post-Graduate Program in Dentistry (Prosthodontics), School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
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Marovic D, Par M, Crnadak A, Sekelja A, Negovetic Mandic V, Gamulin O, Rakić M, Tarle Z. Rapid 3 s Curing: What Happens in Deep Layers of New Bulk-Fill Composites? MATERIALS 2021; 14:ma14030515. [PMID: 33494495 PMCID: PMC7866022 DOI: 10.3390/ma14030515] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/08/2021] [Accepted: 01/19/2021] [Indexed: 12/13/2022]
Abstract
This study assessed the influence of rapid 3 s light curing on the new generation of bulk-fill resin composites under the simulated aging challenge and depths up to 4 mm. Four bulk-fill materials were tested: two materials designed for rapid curing (Tetric PowerFill—PFILL; Tetric PowerFlow—PFLW) and two regular materials (Filtek One Bulk Fill Restorative—FIL; SDR Plus Bulk Fill Flowable—SDR). Three-point bending (n = 10) was used to measure flexural strength (FS) and flexural modulus (FM). In the 3 s group, two 2 mm thick specimens were stacked to obtain 4 mm thickness, while 2 mm-thick specimens were used for ISO group. Specimens were aged for 1, 30, or 30 + 3 days in ethanol. The degree of conversion (DC) up to 4 mm was measured by Raman spectroscopy. There was no difference between curing protocols in FS after 1 day for all materials except PFLW. FM was higher for all materials for ISO curing protocol. Mechanical properties deteriorated by increasing depth (2–4 mm) and aging. ISO curing induced higher DC for PFLW and FIL, while 3 s curing was sufficient for PFILL and SDR. The 3 s curing negatively affected FM of all tested materials, whereas its influence on FS and DC was highly material-specific.
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Affiliation(s)
- Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb 10000, Croatia; (D.M.); (A.C.); (A.S.); (V.N.M.); (Z.T.)
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb 10000, Croatia; (D.M.); (A.C.); (A.S.); (V.N.M.); (Z.T.)
- Correspondence:
| | - Ana Crnadak
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb 10000, Croatia; (D.M.); (A.C.); (A.S.); (V.N.M.); (Z.T.)
| | - Andjelina Sekelja
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb 10000, Croatia; (D.M.); (A.C.); (A.S.); (V.N.M.); (Z.T.)
| | - Visnja Negovetic Mandic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb 10000, Croatia; (D.M.); (A.C.); (A.S.); (V.N.M.); (Z.T.)
| | - Ozren Gamulin
- Institute for Physics and Biophysics, School of Medicine, University of Zagreb, Zagreb 10000, Croatia;
| | - Mario Rakić
- Institute of Physics, Zagreb 10000, Croatia;
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb 10000, Croatia; (D.M.); (A.C.); (A.S.); (V.N.M.); (Z.T.)
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Biocompatibility, mechanical, and bonding properties of a dental adhesive modified with antibacterial monomer and cross-linker. Clin Oral Investig 2020; 25:2877-2889. [PMID: 33006665 DOI: 10.1007/s00784-020-03605-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 09/23/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVES This study investigated the antibacterial, cytotoxicity, and mechanical properties of a dental adhesive modified with quaternary ammonium monomer ((2-acryloyloxyethyl)dimethyldodecylammonium bromide) and cross-linker (bis(2-acryloyloxyethyl)methyldodecylammonium bromide). MATERIALS AND METHODS Monomer (M), cross-linker (C), or a combination of these (M + C) were incorporated into adhesive Adper Single Bond Plus (SB) in 5, 10, or 25% (as wt%). A colony-forming unit and MTT assays were used to evaluate antibacterial properties against Streptococcus mutans and cell viability. Resin-dentin beams (0.9 ± 0.1 mm2) were evaluated for micro-tensile bond strength (μTBS) after 24 h, 6 months, and 3 years. Hourglass specimens were evaluated for ultimate tensile strength (UTS) after 24 h, 1 week, and 6 months. Micro-hardness measurements after softening in ethanol were taken as an indirect assessment of the polymer cross-linking density. Kruskal-Wallis, one-way ANOVA, two-way ANOVA, and Student's t test were used for analysis of the antibacterial, cytotoxicity, μTBS, UTS, and hardness data, all with a significance level of p < 0.05. RESULTS 10%M and 25%M demonstrated a significant reduction in S. mutans relative to SB (p < 0.001). No differences in cytotoxicity were detected for any of the groups. After 6 months, no changes in μTBS were shown for any of the groups. After 3 years, all groups evidenced a significant decrease in μTBS (p < 0.05) except 5%M, 5%C, and 5%M + 5%C. All groups demonstrated either stable or significantly increased UTS after 6 months. Except for the cross-linker groups, a significant decrease in micro-hardness was shown for all groups after softening in ethanol (p < 0.05). CONCLUSIONS A 5-10% of monomer may render the resin antibacterial without a compromise to its mechanical and bonding properties. CLINICAL RELEVANCE Biomodification of a resin adhesive with an antibacterial monomer and cross-linker may help improve the life span of adhesive restorations.
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Bragança GF, Vianna AS, Neves FD, Price RB, Soares CJ. Effect of exposure time and moving the curing light on the degree of conversion and Knoop microhardness of light-cured resin cements. Dent Mater 2020; 36:e340-e351. [PMID: 32950244 DOI: 10.1016/j.dental.2020.08.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 07/07/2020] [Accepted: 08/29/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To evaluate the effect of exposure time and moving the light-curing unit (LCU) on the degree of conversion (DC) and Knoop microhardness (KH) of two resin cements that were light-cured through ceramic. METHODS Two resin cements: AllCem Veneer APS (FGM) and Variolink Esthetic LC (Ivoclar Vivadent) were placed into a 0.3 mm thick matrix in 6 locations representing the canine to canine. The resins were covered with 0.5 mm thick lithium disilicate glass-ceramic (IPS e.max CAD, Ivoclar Vivadent). A motorized device moved the LCUs over the ceramic when the LCU was on. Two single-peak LCUs: Elipar DeepCure-L (3M Oral Care) and Emitter C (Schuster), and one multi-peak: Bluephase G2 (Ivoclar Vivadent) were used with 3 different exposure protocols: a localized exposure centered over each tooth for 10 or 40 s; moving the tip across the 6 teeth for a total exposure time of 10 or 40 s; and moving the tip across the 6 teeth resins for a total exposure time of 60 or 240 s. After 24 h, the DC and KH were measured on the top surfaces and the data was analyzed using three-way ANOVA and Tukey's tests (α = 0.05). RESULTS Interposition of 0.5 mm of ceramic reduced the irradiance received by the resin by approximately 50%. The 40 s localized exposure over each tooth always produced significantly higher DC and KH values. Moving the LCUs with a total exposure time of 10 s resulted in the lowest DC and KH. There was no beneficial effect on the DC or KH when the multi-peak (violet-blue) LCU (Elipar DeepCure-L or Bluephase G2), but the lower light output from a small tip LCU reduced the DC and KH values (Emitter C). SIGNIFICANCE Moving the LCUs when photo-curing light-cured resin cements is not recommended. This study showed that a single-peak LCU could activate a resin cement that uses Ivocerin™ as well as the multi-peak LCU.
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Affiliation(s)
- Gabriel Felipe Bragança
- Biomechanical, Biomaterials and Cell Biology Research Center, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
| | - Arthur Silva Vianna
- School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
| | - Flávio Domingues Neves
- Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada.
| | - Richard Bengt Price
- Department of Occlusion and Prosthodontic, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
| | - Carlos José Soares
- Biomechanical, Biomaterials and Cell Biology Research Center, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
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Kim YS, Choi SH, Lee BN, Hwang YC, Hwang IN, Oh WM, Ferracane JL, Chang HS. Effect of Tack Cure on Polymerization Shrinkage of Resin-based Luting Cements. Oper Dent 2020; 45:E196-E206. [PMID: 32243252 DOI: 10.2341/19-159-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2019] [Indexed: 11/23/2022]
Abstract
CLINICAL RELEVANCE Self-cure after tack cure could result in a lower polymerization shrinkage in some resin-based luting cements, which is closely related to lower degree of cure. SUMMARY
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The effect of rapid high-intensity light-curing on micromechanical properties of bulk-fill and conventional resin composites. Sci Rep 2020; 10:10560. [PMID: 32601442 PMCID: PMC7324583 DOI: 10.1038/s41598-020-67641-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 06/11/2020] [Indexed: 01/08/2023] Open
Abstract
Rapid high-intensity light-curing of dental resin composites is attractive from a clinical standpoint due to the prospect of time-savings. This study compared the effect of high-intensity (3 s with 3,440 mW/cm2) and conventional (10 s with 1,340 mW/cm2) light-curing on micromechanical properties of conventional and bulk-fill resin composites, including two composites specifically designed for high-intensity curing. Composite specimens were prepared in clinically realistic layer thicknesses. Microhardness (MH) was measured on the top and bottom surfaces of composite specimens 24 h after light-curing (initial MH), and after subsequent immersion for 24 h in absolute ethanol (ethanol MH). Bottom/top ratio for initial MH was calculated as a measure of depth-dependent curing effectiveness, whereas ethanol/initial MH ratio was calculated as a measure of crosslinking density. High-intensity light-curing showed a complex material-dependent effect on micromechanical properties. Most of the sculptable composites showed no effect of the curing protocol on initial MH, whereas flowable composites showed 11–48% lower initial MH for high-intensity curing. Ethanol/initial MH ratios were improved by high-intensity curing in flowable composites (up to 30%) but diminished in sculptable composites (up to 15%). Due to its mixed effect on MH and crosslinking density in flowable composites, high-intensity curing should be used with caution in clinical work.
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Dual-curing resin cement with colour indicator for adhesively cemented restorations to dental tissues: Change of colour by curing and some physical properties. Saudi J Biol Sci 2020; 27:395-400. [PMID: 31889862 PMCID: PMC6933191 DOI: 10.1016/j.sjbs.2019.10.009] [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: 09/03/2019] [Revised: 10/06/2019] [Accepted: 10/27/2019] [Indexed: 11/22/2022] Open
Abstract
The study was aimed to investigate a color indicator containing dual curing resin composite luting cement and to plot the color change to the time of solidification of the cement. In addition some physical properties were studied. Specimens were made of a dual-cure resin cement (Maxcem Elite™ Chroma, Kerr, Orange, CA, USA) and polymerized by autopolymerization only, or with light initiated polymerization. A spectrophotometer was used to quantify the color change of the cement as plotted with the curing time. The efficacy of the curing process was studied by measuring water sorption and the ultimate flexural properties of the cement. The results showed that the flexural strength of cement after autopolymerization was 27.3 MPa and after light initiated polymerization 48.1 MPa. Young’s modulus of bending was 2089.3 MPa and 3781.5 MPa respectively for the same cement samples. Water sorption after two weeks for the autopolymerization cement samples was −1.12 wt% and for the light initiated polymerization samples 0.56 wt%. Non-parametric Spearman’s correlation was measured for autopolymerized cement samples between variables for color and solidification load (N), which showed a strong correlation between curing process and color change (p < 0.05). There was a correlation between the color change and degree of monomer conversion of the dual curing resin composite luting cement which contained a color indicator system for polymerization reaction. The study also suggested that autopolymerization only resulted in suboptimal polymerization of the cement. By additional light curing considerably higher flexural properties were obtained.
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Paes PNG, Miranda MSD, Sampaio-Filho HR, Correr-Sobrinho L. Influence of activation mode, fatigue, and ceramic interposition on resin cements' diametral tensile strength. Braz Oral Res 2019; 33:e083. [PMID: 31460609 DOI: 10.1590/1807-3107bor-2019.vol33.0083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 07/02/2019] [Indexed: 11/22/2022] Open
Abstract
This study evaluated the influence of activation modes, on Diametral Tensile Strength (DTS) of dual cured resin cements subjected to a Mechanical Fatigue test (MF). Four dual-cured resin cements (RelyX UNICEM [U], RelyX ARC [A], ENFORCE [E] and Nexus 2 [N]) were activated by three different curing modes as follows: Self-Curing (SC), Dual Cure activation with photoactivation executed directly (DC) and Dual Cure activation with Photoactivation Through Porcelain (DCTP). After 24 hours, half of the sample was subjected to 30.000 fatigue cycles at 1 Hz frequency and 12 N load. Then, all specimens were subjected to DTS test in Instron Universal Testing Machine and data were analyzed by three-way ANOVA and Tukey's Test (5%). The results of DTS test means (MPa) and standard deviation, for each cement factor activated by SC, DC and DCTP was respectively: U (28.12 ± 5.29; 37.44 ± 6.49 and 40.10 ± 4.39), A (49.68 ± 8.42; 55.12 ± 5.16 and 63.43 ± 6.92), E (49.12 ± 3.89; 56.42 ± 8.88 and 56.96 ± 6.45) and N (61.89 ± 11.21; 59.26 ± 9.47 and 62.56 ± 10.93). Turkey's test indicated that DC is related to the highest DTS values; Nexus 2 DTS remained the same independently of activation mode and that the Porcelain disk interposition enhanced DTS only for RelyX ARC the ANOVA statistical test indicated that MF didn't alter the DTS values for all experimental groups. MF results clinical implication is that all cements tested exhibited, in an immediate loading, good cross linked bonds quality.
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Affiliation(s)
- Paula Nunes Guimarães Paes
- Universidade do Estado do Rio de Janeiro - UERJ, Faculty of Dentistry, Department of Dentistry, Rio de Janeiro, RJ, Brazil
| | - Mauro Sayão de Miranda
- Universidade do Estado do Rio de Janeiro - UERJ, Faculty of Dentistry, Department of Dentistry, Rio de Janeiro, RJ, Brazil
| | - Hélio Rodrigues Sampaio-Filho
- Universidade do Estado do Rio de Janeiro - UERJ,, Faculty of Dentistry, Department of Prosthodontics, Rio de Janeiro, RJ, Brazil
| | - Lourenço Correr-Sobrinho
- Universidade Estadual de Campinas - Unicamp, Piracicaba School of Dentistry, Department of Restorative Dentistry, Piracicaba, SP, Brazil
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Lima AF, Salvador MVO, Dressano D, Saraceni CHC, Gonçalves LS, Hadis M, Palin WM. Increased rates of photopolymerisation by ternary type II photoinitiator systems in dental resins. J Mech Behav Biomed Mater 2019; 98:71-78. [PMID: 31203099 DOI: 10.1016/j.jmbbm.2019.06.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 12/26/2022]
Abstract
To evaluate the effects of Type I and Type II photoinitiator systems on curing efficiency, degree of conversion (DC) and chemico-physical properties of resin based materials. A comonomer base containing 50%wt 2.2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (bis-GMA) and 50%wt triethyleneglycol dimethacrylate (TEGDMA) was formulated with either 0.5 or 1mol% of Type II camphoroquinone (CQ), Type I monoacylphosphine oxide (MAPO) or bis-acylphosphine oxide (BAPO) photoinitiators. The Type II system was either a binary (1: 2 CQ:amine) or ternary system (1: 2 CQ:amine + 0.5 mol% DPI). Degree and rate of polymerization was measured by Fourier Transform Infrared Spectroscopy (FTIR). Knoop micro-hardness prior to and following ethanol immersion was assessed. Flexural strength and modulus was measured under three-point bend test. Water sorption and solubility was also evaluated. The photoinitiator absorption spectra and the total absorbed energy per unit volume (Eabs) for 0.5mol% photoinitiator in each material was calculated. Despite the reduced total absorbed energy per unit volume for CQ based systems, ternary Type II system significantly improved curing efficiency (P < 0.05) compared to both Type I photoinitiators and degree of conversion compared to MAPO only, whilst exhibiting comparable mechanical and physical properties compared to both Type I based materials at equivalent molar concentrations of photoinitiator (P > 0.05). Ternary Type II systems is an efficient alternative to improve the polymerization of resin materials, promoting similar or even better properties than Type I initiators. DPI can increase the reactivity of CQ systems and promote polymerization rates superior than Type I photoinitiators.
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Affiliation(s)
- Adriano Fonseca Lima
- Dental Research Division, Paulista University, Sao Paulo Brazil. Rua Doutor Bacelar, 1212. CEP: 04026-002, Sao Paulo, Brazil.
| | | | - Diogo Dressano
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil. Av Limeira, 901 Mail Box 52, Piracicaba, Sao Paulo, 13414-903, Brazil.
| | - Cintia Helena Coury Saraceni
- Dental Research Division, Paulista University, Sao Paulo Brazil. Rua Doutor Bacelar, 1212. CEP: 04026-002, Sao Paulo, Brazil.
| | - Luciano Souza Gonçalves
- Department of Conservative Dentistry, Federal University of Rio Grande do Sul School of Dentistry, Av. Paulo Gama, 110 - Farroupilha, Porto Alegre, RS, 90040-060, Porto Alegre, RS, Brazil.
| | - Mohammed Hadis
- Biomaterials Unit, University of Birmingham, College of Medical and Dental Sciences, School of Dentistry, St Chad's Queensway, Birmingham, B4 6NN, UK.
| | - William M Palin
- Biomaterials Unit, University of Birmingham, College of Medical and Dental Sciences, School of Dentistry, St Chad's Queensway, Birmingham, B4 6NN, UK.
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Spajic J, Par M, Milat O, Demoli N, Bjelovucic R, Prskalo K. Effects of Curing Modes on the Microhardness of Resin-modified Glass Ionomer Cements. Acta Stomatol Croat 2019; 53:37-46. [PMID: 31118531 PMCID: PMC6508928 DOI: 10.15644/asc53/1/4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Objective This study evaluated the effects of curing modes on surface microhardness of visible light-cured resin-modified glass ionomer cements (VLC RMGIC) and a giomer after different storage periods in comparison to auto-cured resin-modified glass ionomer cements (AC RMGIC). Materials and Methods The following materials were used: VLC RMIC: Fuji II LC Improved, Photac Fil Quick Aplicap, AC RMGIC: Fuji Plus, Fuji VIII and Giomer: Beautifil II. The measurements of microhardness were performed using a Vickers test (100 g loads were applied for 10 s) in the following time intervals: immediately after the recommended cure and after 1, 7 and 14 days of immersion in distilled water. Five samples (d=4 mm, h=2 mm) were prepared for each combination of curing mode and tested material. Results After 14 days, an improvement of microhardness was evident in all tested materials. The full factorial ANOVA identified a highly significant (p<0.001) effect of the factors “material”, “time” and “curing mode (“low”, “soft“, „high”) for the light-cured materials Beautifil II, Fuji II LC and Photac Fil Quick. There was a statistically significant difference in the microhardness between different material types (Beautifil II˃Fuji II LC˃Photac Fil Quick˃Fuji Plus˃Fuji VIII) and curing modes (low ˂soft ˂high). Conclusions Material type had the greatest impact on microhardness, followed by the factor of time, while curing modes showed a considerably smaller influence on microhardness of the light-cured materials.
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Affiliation(s)
| | - Matej Par
- Department of Endodontics and Restorative Dental Medicine School of Dental Medicine University of Zagreb, Gundulićeva 5, Zagreb
| | | | | | | | - Katica Prskalo
- Department of Endodontics and Restorative Dental Medicine School of Dental Medicine University of Zagreb, Gundulićeva 5, Zagreb
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Pils D, Baeppler RJ, Junker R, Kielbassa AM, Nothdurft FP. Application of a standard autoclaving protocol does not harm structural integrity of two-piece zirconia abutments under detachment force testing. Clin Oral Investig 2019; 23:3133-3137. [PMID: 31076883 DOI: 10.1007/s00784-019-02926-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 04/30/2019] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Aim was to assess the influence of a standard autoclaving protocol on the retention of zirconia abutments glued on titanium bases in two-piece implant abutments. MATERIALS AND METHODS Twenty-four CAD/CAM-generated zirconia abutments were adhesively cemented on prefabricated titanium bases. Before mechanical and thermal aging, the specimens were divided into two groups. Group 1 was subjected to a standard steam autoclaving protocol and Group 2 remained untreated (control). The tensile strength in all specimens was evaluated by a standardized pull-off test limited to a maximum force of 1000 N. RESULTS Eleven samples in both groups could be subjected to pull-off testing. Ten samples in Group 1 and three samples in Group 2 failed, while all others reached the maximum pull-off force. This difference was statistically significant. The mean retention values for the failed samples were 694.53 ± 369.10 N in Group 1 and 890.78 ± 25.90 N in Group 2. This difference was not statistically significant. CONCLUSIONS A standard autoclaving protocol does not reduce detachment force of two-piece zirconia abutments. CLINICAL RELEVANCE Clinical sterilization processes as recommended by regulatory authorities seem to be harmless to the structural integrity of two-piece zirconia implant abutments, at least with regard to the retention of the components.
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Affiliation(s)
- Dieter Pils
- Pils Zahntechnik GmbH, Bruck an der Glocknerstrasse, Austria
- Centre for Prosthodontics and Biomaterials, Danube Private University (DPU), Krems an der Donau, Austria
| | - Ralf J Baeppler
- Centre for Prosthodontics and Biomaterials, Danube Private University (DPU), Krems an der Donau, Austria
| | - Rüdiger Junker
- Centre for Prosthodontics and Biomaterials, Danube Private University (DPU), Krems an der Donau, Austria
| | - Andrej M Kielbassa
- Centre for Operative Dentistry, Periodontology, and Endodontology, Danube Private University (DPU), Krems an der Donau, Austria
| | - Frank P Nothdurft
- Department of Prosthetic Dentistry and Dental Materials Sciences, Saarland University, Homburg Campus, Bldg. 71.2, 66421, Homburg, Saar, Germany.
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Al-Zain AO, Eckert GJ, Lukic H, Megremis S, Platt JA. Polymerization pattern characterization within a resin-based composite cured using different curing units at two distances. Clin Oral Investig 2019; 23:3995-4010. [PMID: 30737620 DOI: 10.1007/s00784-019-02831-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 01/25/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To investigate the relationship of the irradiance-beam-profile areas from six different light-curing units (LCUs) with the degree of conversion (DC), microhardness (KH), and cross-link density (CLD) throughout a resin-based composite (RBC) cured at two clinically relevant distances, and to explore the correlations among them. MATERIALS AND METHODS A mapping approach was used to measure DC using micro-Raman spectroscopy, KH using a Knoop indentor on a hardness tester, and %KH reduction after ethanol exposure, as an indicator for CLD within a nano-hybrid RBC increment (n = 3) at various depths. These sample composites were cured from two distances while maintaining the radiant exposure, using six different light-curing units: one quartz-tungsten-halogen; two single and three multiple-emission-peak light-emitting-diode units. Irradiance beam profiles were generated for each LCU at both distances, and localized irradiance values were calculated. Points across each depth were analyzed using repeated measures ANOVA. Correlations across multiple specimen locations and associations between beam uniformity corresponding with polymerization measurements were calculated using linear mixed models and Pearson correlation coefficients. RESULTS Significant non-uniform polymerization patterns occurred within the specimens at various locations and depths. At 2-mm curing distance, the localized DC = 52.7-76.8%, KH = 39.0-66.7 kg/mm2, and %KH reduction = 26.7-57.9%. At 8-mm curing distance, the localized DC = 50.4-78.6%, KH = 40.3-73.7 kg/mm2, and %KH reduction = 28.2-56.8%. The localized irradiance values were weakly correlated with the corresponding DC, KH, and %KH reduction, with only a few significant correlations (p < 0.05). CONCLUSIONS Although significant differences were observed at each depth within the specimens, the localized irradiance values for all LCUs did not reflect the polymerization pattern and did not seem to have a major influence on polymerization patterns within the RBC, regardless of the curing distance. CLINICAL RELEVANCE Commonly used LCUs do not produce uniform polymerization regardless of the curing distance, which may contribute to the risk of RBC fracture.
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Affiliation(s)
- Afnan O Al-Zain
- Restorative Dentistry Department, Faculty of Dentistry, King Abdulaziz University, P.O. Box: 80209, Jeddah, 21589, Saudi Arabia.
| | - George J Eckert
- Department of Biostatistics, Indiana University School of Medicine, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Henry Lukic
- Research and Standards, American Dental Association Science Institute, Chicago, IL, USA
| | - Spiro Megremis
- Research and Standards, American Dental Association Science Institute, Chicago, IL, USA
| | - Jeffrey A Platt
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
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Lima RBW, Murillo-Gómez F, Sartori CG, De Góes MF. Effect of light absence or attenuation on biaxial flexural strength of dual-polymerized resin cements after short- and long-term storage. J ESTHET RESTOR DENT 2018; 31:80-87. [PMID: 30394656 DOI: 10.1111/jerd.12427] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 07/16/2018] [Accepted: 09/05/2018] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To evaluate whether biaxial flexural strength (BFS) of dual resin cements is affected by light absence or attenuation, storage time, or cements' chemical nature. MATERIALS AND METHODS One hundred and twenty disk-shaped specimens were made from each cement (non-self-adhesive cement and self-adhesive cement) using Teflon molds on a controlled temperature surface (35°C). Specimens were polymerized as follows (N = 30): self-cured, directly light-cured, light-cured at a distance of 6 mm between the light tip and the specimen, and through a 6-mm thick composite resin barrier (indirectly light-cured). Each group was divided (N = 10) for storage purposes (15 minutes, 24 hours, and 6 months). Specimens were placed into a biaxial-flexure jig and a vertical load was applied until failure. The BFS values were subjected to generalized linear models statistical analysis and Weibull distributions (α = 0.05). RESULTS After 15 minutes aging, neither material achieved enough polymerization to perform the BFS test when polymerized using the self-curing mode. The self-adhesive product demonstrated much lower variation in strength with storage time than did the non-self-curing cement. CONCLUSIONS Attenuated/light-curing reduced BFS values only for 15-minutes storage period for both materials. Flexural strength of the self-adhesive cement was less affected by light absence/attenuation and storage time. CLINICAL SIGNIFICANCE Biaxial flexural strength of a self-adhesive resin cement is less sensitive to variation in light application and storage time than is a non-self-adhesive cement.
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Affiliation(s)
- Renally B W Lima
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, São Paulo, Brazil
| | - Fabián Murillo-Gómez
- Department of Restorative Dentistry, School of Dentistry, University of Costa Rica, San José, Costa Rica
| | - Cristiana G Sartori
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, São Paulo, Brazil
| | - Mário F De Góes
- Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, São Paulo, Brazil
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Silva Prezotto AF, Silva DB, Vitti RP, Sinhoreti MAC, Brandt WC. Light curing and ratio of glass/fumed silica fillers on degree of conversion and mechanical properties of experimental composite resins. J Appl Polym Sci 2018. [DOI: 10.1002/app.47008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- A. F. Silva Prezotto
- University of CampinasPiracicaba Dental School, Department Restorative Dentistry Piracicaba SP Brazil
| | - D. B. Silva
- University of Santo AmaroSchool of Dentistry, Department of Implantology São Paulo SP Brazil
| | - R. P. Vitti
- University of TaubatéSchool of Dentistry, Department of Prosthodontics Taubaté SP Brazil
| | - M. A. C. Sinhoreti
- University of CampinasPiracicaba Dental School, Department Restorative Dentistry Piracicaba SP Brazil
| | - W. C. Brandt
- University of Santo Amaro, School of DentistryDepartment of Implantology São Paulo SP Brazil
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Moreira AG, Cuevas-Suárez CE, da Rosa WLDO, Ogliari AO, Petzhold CL, Piva E, Ogliari FA, Lima GDS. Piperonyl methacrylate: Copolymerizable coinitiator for adhesive compositions. J Dent 2018; 79:31-38. [PMID: 30248382 DOI: 10.1016/j.jdent.2018.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 09/13/2018] [Accepted: 09/18/2018] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVES This study describes the synthesis of piperonyl methacrylate (PipM) and evaluates its effect when used as coinitiator in the photoinitiated radical polymerization of experimental adhesive resins. METHODS PipM was synthetized through an esterification reaction and characterized by FTIR and 1H NMR spectroscopy. Adhesive resins containing camphorquinone as photoinitiator and PipM or ethyl-4-dimethyl amine benzoate (EDAB) as coinitiators were formulated. Scotchbond Multipurpose (SBMP) adhesive was used as commercial reference. All materials were analyzed for polymerization kinetics, flexural strength, elastic modulus, water sorption/solubility, shear bond strength to bovine enamel and dentin, characterization of hybrid layer by scanning electron microscopy (SEM), microbiological direct contact test, and cytotoxicity. RESULTS The adhesive with PipM presented higher degree of conversion and lower sorption/solubility when compared with other groups. Shear bond strength to enamel and dentin were similar for PipM and EDAB materials. The percentage of cellular viability was close to 100% and similar in the experimental groups and the commercial reference. CONCLUSIONS PipM presented similar or superior performance to the tertiary amine used as control, representing a potential alternative coinitiator for photopolymerizable dental materials. CLINICAL SIGNIFICANCE PipM could be potentially useful in the formulations of adhesive systems with enhanced chemical properties, which could mean improvement in the longevity of composite resin restorations.
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Affiliation(s)
| | - Carlos Enrique Cuevas-Suárez
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil; Dental Materials Laboratory, Academic Area of Dentistry, Autonomous University of Hidalgo State, HGO, Mexico
| | | | - Aline Oliveira Ogliari
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Cesar Liberato Petzhold
- Organic Chemistry Department, Chemistry Institute, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Evandro Piva
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Fabrício Aulo Ogliari
- Center for Technological Development, Faculty of Materials Engineering, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Giana da Silveira Lima
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
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Lima MO, Catelan A, Marchi GM, Lima DA, Martins LR, Aguiar FH. Influence of pre-heating and ceramic thickness on physical properties of luting agents. J Appl Biomater Funct Mater 2018; 16:252-259. [PMID: 29983080 DOI: 10.1177/2280800018782842] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
PURPOSE The objective of this in vitro study was to evaluate the influence of ceramic thickness and pre-heating of luting agents on their physical properties. MATERIALS AND METHODS The materials RelyX Arc, RelyX Ultimate, RelyX Veneer, and Filtek Z350 Flow were handled at different temperatures (23°C or 54°C), inserted into matrix, and photoactivated through ceramic disks (0.75 mm or 1.5 mm). The following tests were performed ( n=8): degree of conversion, Knoop Hardness, cross-link density, water sorption, solubility, and ultimate tensile strength. Data were analyzed using three-way analysis of variance and Tukey's test (α=0.05). RESULTS Regarding ceramic thickness, the thinnest ceramic resulted in higher values of Knoop Hardness ( p=0.027). The lowest temperature (23°C) resulted in a higher solubility ( p=0.0257), and water sorption ( p=0.0229) values. There was also statistical difference among the materials: RelyX Arc showed a higher degree of conversion and ultimate tensile strength, followed by RelyX Veneer, RelyX Ultimate, and Filtek Z350 Flow. For Knoop Hardness and cross-link density tests, RelyX Ultimate showed the highest values, followed by RelyX Arc, RelyX Veneer, and Filtek Z350 Flow. For water sorption and solubility, RelyX Veneer showed the highest values, followed by RelyX Arc, RelyX Ultimate, and Filtek Z350 Flow. CONCLUSION Pre-heating interfered with water sorption and solubility, whereas ceramic thickness only affected Knoop Hardness; the physical properties of the materials are dependent on their composition.
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Affiliation(s)
- Michele O Lima
- 1 Department of Restorative Dentistry, State University of Campinas, Piracicaba, Brazil
| | - Anderson Catelan
- 2 Department of Dentistry, University of Western São Paulo, Presidente Prudente, Brazil
| | - Giselle M Marchi
- 1 Department of Restorative Dentistry, State University of Campinas, Piracicaba, Brazil
| | - Débora Anl Lima
- 1 Department of Restorative Dentistry, State University of Campinas, Piracicaba, Brazil
| | - Luís Rm Martins
- 1 Department of Restorative Dentistry, State University of Campinas, Piracicaba, Brazil
| | - Flávio Hb Aguiar
- 1 Department of Restorative Dentistry, State University of Campinas, Piracicaba, Brazil
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Alrahlah A, Khan R, Alotaibi K, Almutawa Z, Fouad H, Elsharawy M, Silikas N. Simultaneous Evaluation of Creep Deformation and Recovery of Bulk-Fill Dental Composites Immersed in Food-Simulating Liquids. MATERIALS 2018; 11:ma11071180. [PMID: 29996519 PMCID: PMC6073768 DOI: 10.3390/ma11071180] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 11/16/2022]
Abstract
The aim of this study is to compare the creep/recovery behavior of bulk-fill dental composites after storage in various food simulating organic solvents. For this purpose, five different resin-composites (four bulk-fills and one conventional) were used. A total of 20 rectangular specimens (14 mm × 3 mm × 0.7 mm) were prepared by filling the resin-composites in Teflon mold. All of the specimens for each material (n = 5) were divided into four groups namely dry (control), distilled water (DW), artificial saliva, and absolute ethanol. The specimens were subjected to three-point bending creep test during immersion directly. A constant load of 2 N was used for each specimen with loading and unloading time 2 h each. RESULTS SF2 and XF showed a lower creep strain % after immersion, ranging from 0.44 (dry) to 0.75 (saliva) and 0.43 (dry) to 0.80 (ethanol), respectively. TNC BF depicts the maximum creep strain % ranging from 1.24% (dry) to 2.87% (ethanol) followed by FBF ranging from 1.17 (dry) to 2.59 (ethanol). However, the conventional material (GR) showed lower creep strain after immersion ranging from 0.28 to 0.54. Moreover, SF2 resulted in the highest creep recovery in all of the composites groups, as well as conventional material. The other composite groups showed lower creep recovery as compared to the conventional material (GR). The creep strain % for all the bulk-fill composites materials were increased during immersion in the liquids. However, for the conventional material, the creep deformation is decreased after immersion. SF2 showed the highest percentage of creep recovery among the bulk-fill composites, followed by XF.
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Affiliation(s)
- Ali Alrahlah
- Restorative Dental Sciences Department, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia.
- Engineer Abdullah Bugshan research chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia.
| | - Rawaiz Khan
- Engineer Abdullah Bugshan research chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia.
| | - Khalid Alotaibi
- Dental intern, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia.
| | - Ziad Almutawa
- Dental intern, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia.
| | - H Fouad
- Applied Medical Science Department, Community College, King Saud University, Riyadh 11545, Saudi Arabia.
- Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Helwan 11792, Egypt.
| | - Mohamed Elsharawy
- Dental Biomaterials Research Chair, King Saud University, Riyadh 11433, Saudi Arabia.
| | - Nikolaos Silikas
- Dentistry, School of Medical Sciences, University of Manchester, Manchester M13 9PL, UK.
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Burey A, dos Reis PJ, Santana Vicentin BL, Dezan Garbelini CC, Grama Hoeppner M, Appoloni CR. Polymerization shrinkage and porosity profile of dual cure dental resin cements with different adhesion to dentin mechanisms. Microsc Res Tech 2017; 81:88-96. [DOI: 10.1002/jemt.22960] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/22/2017] [Accepted: 10/12/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Adrieli Burey
- Student of the Master Degree Program in Odontology at Universidade Estadual de Londrina - UEL, Londrina; Paraná Brasil
| | - Paulo José dos Reis
- Department of Physics; State University of Central West - UNICENTRO; Guarapuava Paraná Brasil
| | | | | | - Márcio Grama Hoeppner
- Department of Restorative Odontology; State University of Londrina - UEL; Londrina Paraná Brasil
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Bitter K, Maletic A, Neumann K, Breschi L, Sterzenbach G, Taschner M. Adhesive Durability Inside the Root Canal Using Self-adhesive Resin Cements for Luting Fiber Posts. Oper Dent 2017; 42:E167-E176. [PMID: 28976849 DOI: 10.2341/17-017-l] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES The aim of the study was to investigate the effects of various self-adhesive resin cements on the push-out bond strengths and nanoleakage expression at the luting interfaces of fiber posts immediately and after one year of aging. METHODS AND MATERIALS One hundred forty-four extracted human anterior teeth were endodontically treated. After post space preparation, fiber posts were luted using five commercially available self-adhesive resin (SAR) cements and a core build-up material applied with a self-etch adhesive (BF: Bifix SE/Rebilda Post, VOCO; CSA: Clearfil SA Cement/Rely X Fiber Post, 3M ESPE; RX: RelyX Unicem 2/Rely X Fiber Post, 3M ESPE; SPC: Speed Cem/FRC Postec, Ivoclar Vivadent; SMC: Smart Cem/X Post, Dentsply; RB: Rebilda DC-Futurabond/Rebilda Post; n=22). For each group, half of the specimens were subjected to thermocycling (TC) (5°C-55°C, 10,000 cycles) and stored humid for one year at 37°C. Push-out bond strength data of six slices (thickness 1 mm) per root and nanoleakage expression of representative specimens were evaluated after 24 hours (baseline) and after TC and storage for one year (aging), respectively. RESULTS Bond strength differed significantly among resin cements (p<0.0005) and the location inside the root canal (p<0.0005), but not by aging (p=0.390; repeated-measures analysis of variance). SMC (14.6±5.8 MPa) and RX (14.1±6.8 MPa) revealed significantly higher bond strength compared to BF (10.6±5.4 MPa) and RB (10.0±4.6 MPa) but differed not significantly from SPC (12.8±4.8) MPa; CSA (6.1±4.6 MPa) revealed significantly lower bond strength compared to all other investigated materials (p<0.05; Tukey Honestly Significantly Different). Qualitative nanoleakage analysis revealed more silver deposits at the interface in all groups after aging. For CSA, a large amount of silver deposits inside the cement was also observed at baseline and after aging. CONCLUSIONS Fiber post luting using SAR cements demonstrated reliable bond strengths. Product-specific differences and initial degradation effects could be demonstrated.
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The mechanical and photoelastic properties of 3D printable stress-visualized materials. Sci Rep 2017; 7:10918. [PMID: 28883498 PMCID: PMC5589947 DOI: 10.1038/s41598-017-11433-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 08/24/2017] [Indexed: 11/23/2022] Open
Abstract
Three-dimensional (3D) printing technology integrating frozen stress techniques has created a novel way to directly represent and characterize 3D interior discontinuities and the full-field stress induced by mining- or construction-related disturbances of deeply buried rock masses. However, concerns have been raised about the similitude between the mechanical behaviours of the printed model and its prototype rock mass. Ensuring the mechanical properties of the printable materials are as close as possible to those of real rock mass is of critical significance. In this work, a transparent, light, photosensitive polymer material was investigated for applications in frozen stress tests. The chemical composition of the material was determined by integrating the results of infrared spectroscopy (IR spectroscopy), X-ray diffraction (XRD), pyrolysis, gas chromatography and mass spectrometry (PY-GC/MS). Measures to improve the mechanical properties of the printable material, including printing orientation, post-processing, and temperature control, were evaluated by comparing the treated material with its prototype rock. The optical stress sensitivity of the material, including stress-visualized properties and stress-frozen performance, was also tested. This study offers an understanding of how printable materials should be modified to better simulate real rock masses, in terms of not only their geological geometry but also their mechanical performance.
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Yap AUJ, Pandya M, Toh WS. Depth of cure of contemporary bulk-fill resin-based composites. Dent Mater J 2017; 35:503-10. [PMID: 27252008 DOI: 10.4012/dmj.2015-402] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study evaluated the depth of cure (DOC) of packable and flowable bulk-fill resin-based composites (RBCs) including PRG (prereacted glass ionomer) and short-fiber materials. The materials were placed in a black split-mold with a 7 mm deep recess and cured at 700 mW/cm(2) for 20 s using a LED curing light. DOC was assessed using the ISO scraping and Knoops hardness tests. Data (n=5) were computed and analyzed using one-way ANOVA/Scheffe's post hoc test (p<0.05). ISO DOC ranged from 3.66 to 2.54 mm while DOC based on hardness testing ranged from 3 to 1.5 mm. For all materials, a decrease in hardness was observed with increasing depths. The DOC of bulk-fill RBCs was product dependent and greater than standard composites. At 4 mm depth, none of the bulk-fill RBCs had a depth: top hardness ratio of 0.8 and above.
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Al-Zain AO, Eckert GJ, Lukic H, Megremis SJ, Platt JA. Degree of conversion and cross-link density within a resin-matrix composite. J Biomed Mater Res B Appl Biomater 2017; 106:1496-1504. [DOI: 10.1002/jbm.b.33960] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/22/2017] [Accepted: 07/04/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Afnan O. Al-Zain
- Department of Operative Dentistry; Faculty of Dentistry, King Abdulaziz University; Jeddah Kingdom of Saudi Arabia
- Department of Biomedical and Applied Sciences; Indiana University School of Dentistry, Indiana University Purdue University Indianapolis; Indianapolis IN
| | - George J. Eckert
- Biostatistician Supervisor; Department of Biostatistics, Indiana University School of Medicine, Indiana University Purdue University Indianapolis; Indianapolis IN
| | - Henry Lukic
- Research and Laboratories, American Dental Association Division of Science; Chicago IL
| | - Spiro J. Megremis
- Research and Laboratories, American Dental Association Division of Science; Chicago IL
| | - Jeffrey A. Platt
- Department of Biomedical and Applied Sciences; Indiana University School of Dentistry, Indiana University Purdue University Indianapolis; Indianapolis IN
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Eweis AH, Yap AUJ, Yahya NA. Dynamic analysis of bulk-fill composites: Effect of food-simulating liquids. J Mech Behav Biomed Mater 2017; 74:183-188. [PMID: 28605721 DOI: 10.1016/j.jmbbm.2017.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 06/05/2017] [Indexed: 10/19/2022]
Abstract
This study investigated the effect of food simulating liquids on visco-elastic properties of bulk-fill restoratives using dynamic mechanical analysis. One conventional composite (Filtek Z350 [FZ]), two bulk-fill composites (Filtek Bulk-fill [FB] and Tetric N Ceram [TN]) and a bulk-fill giomer (Beautifil-Bulk Restorative [BB]) were evaluated. Specimens (12 × 2 × 2mm) were fabricated using customized stainless steel molds. The specimens were light-cured, removed from their molds, finished, measured and randomly divided into six groups. The groups (n = 10) were conditioned in the following mediums for 7 days at 37°C: air (control), artificial saliva (SAGF), distilled water, 0.02N citric acid, heptane, 50% ethanol-water solution. Specimens were assessed using dynamic mechanical testing in flexural three-point bending mode and their respective mediums at 37°C and a frequency range of 0.1-10Hz. The distance between the supports were fixed at 10mm and an axial load of 5N was employed. Data for elastic modulus, viscous modulus and loss tangent were subjected to ANOVA/Tukey's tests at significance level p < 0.05. Significant differences in visco-elastic properties were observed between materials and mediums. Apart from bulk-fill giomer, elastic modulus was the highest after conditioning in heptane. No apparent trends were noted for viscous modulus. Generally, loss tangent was the highest after conditioning in ethanol. The effect of food-simulating liquids on the visco-elastic properties of bulk-fill composites was material and medium dependent.
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Affiliation(s)
- Ahmed Hesham Eweis
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Adrian U-Jin Yap
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia; Department of Dentistry, Ng Teng Fong General Hospital, National University Health System, Singapore
| | - Noor Azlin Yahya
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia.
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Food Simulating Organic Solvents for Evaluating Crosslink Density of Bulk Fill Composite Resin. Int J Dent 2017; 2017:1797091. [PMID: 28487739 PMCID: PMC5405598 DOI: 10.1155/2017/1797091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/11/2017] [Accepted: 03/29/2017] [Indexed: 11/17/2022] Open
Abstract
Objectives. To evaluate crosslink densities of two bulk fill composite resins and determine if the used Food Simulating Organic Solvent (FSOS) affected them. Methods. Forty specimens were prepared from SureFill and SonicFill bulk fill composite resins, 20 each. All specimens were stored dry for 24 h. Each group was divided into 2 subgroups: stored in ethanol (E) 75% or in methyl ethyl ketone (MEK) 100% for 24 h. Crosslink density was evaluated by calculating the difference between the Vickers hardness numbers of the specimens stored dry and after their storage in FSOS. The data were statistically analyzed using t-test. Results. The means of crosslink density in E and MEK were 6.99% and 9.44% for SureFill and 10.54% and 11.92% for SonicFill, respectively. t-test displayed significant differences between crosslink densities of SureFill and SonicFill: (P < 0.0001) in E and (P = 0.02) in MEK and between crosslink densities of SureFill in E and MEK (P = 0.02). Conclusions. Crosslink density of bulk fill composite resin can be evaluated using E or MEK. SureFill has higher crosslink density than SonicFill in both E and MEK.
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Karakis D, Yıldırım-Bicer AZ, Dogan A, Koralay H, Cavdar S. Effect of self and dual-curing on degree of conversion and crosslink density of dual-cure core build-up materials. J Prosthodont Res 2017; 61:210-216. [DOI: 10.1016/j.jpor.2016.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 04/22/2016] [Accepted: 05/26/2016] [Indexed: 11/30/2022]
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Fadanelli MA, Amaral FLBD, Basting RT, Turssi CP, Sotto-Maior BS, França FMG. Effect of Steam Autoclaving on the Tensile Strength of Resin Cements Used for Bonding Two-Piece Zirconia Abutments. J ORAL IMPLANTOL 2017; 43:87-93. [PMID: 27967320 DOI: 10.1563/aaid-joi-d-16-00018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to evaluate the effects of steam autoclave sterilization on the tensile strength of two types of resin cements used to bond customized CAD/CAM zirconia abutments onto titanium bases. Forty sets of zirconia abutments cemented to screwed titanium bases of implants analogs were divided into 4 groups (n = 10). Two groups were treated with a conventional chemically activated resin cement (ML, Multilink Ivoclar Vivadent) and the other two groups with a self-adhesive dual resin cement (RelyX U200, 3M ESPE). One group from each cement was submitted to steam autoclaving. The autoclave sterilization cycle was performed after 72 hours of cementation for 15 minutes at 121°C and 2.1 Kgf/cm2. The samples were subjected to tensile strength testing in a universal testing machine (200 Kgf, 0.5 mm/min), from which the means and standard deviations were obtained in Newtons. Results showed (via ANOVA and Tukey's test; α = 0.05) that in the absence of steam autoclaving, no difference was observed in tensile strength between the cements tested: ML: 344.87 (93.79) and U200: 280 (92.42) (P = .314). Steam autoclaving, however, significantly increased tensile strength for the ML: 465.42 (87.87) compared to U200: 289.10 (49.02) (P < .001). Despite the significant increase in the ML samples (P = .013), autoclaving did not affect the tensile strength of the U200 samples (P > 0.05). The authors concluded that steam autoclaving increases the mean tensile strength of the chemically activated cement compared to the dual-cure self-adhesive cement. The performance of both cements evaluated was similar if the sterilization step was disconsidered.
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Lau CC, Bayazit MK, Knowles JC, Tang J. Tailoring degree of esterification and branching of poly(glycerol sebacate) by energy efficient microwave irradiation. Polym Chem 2017. [DOI: 10.1039/c7py00862g] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A branched poly(glycerol sebacate) prepolymer has been successfully synthesised via single mode microwave irradiation with an improved reaction rate and controllable properties.
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Affiliation(s)
- Chi Ching Lau
- Department of Chemical Engineering
- University College London
- London WC1E 7JE
- UK
| | | | - Jonathan Campbell Knowles
- Division of Biomaterials and Tissue Engineering
- UCL Eastman Dental Institute
- London
- UK
- Department of Nanobiomedical Science & BK21 Plus NBM Global Research Center for Regenerative Medicine
| | - Junwang Tang
- Department of Chemical Engineering
- University College London
- London WC1E 7JE
- UK
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Heintze SD, Ilie N, Hickel R, Reis A, Loguercio A, Rousson V. Laboratory mechanical parameters of composite resins and their relation to fractures and wear in clinical trials-A systematic review. Dent Mater 2016; 33:e101-e114. [PMID: 27993372 DOI: 10.1016/j.dental.2016.11.013] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/29/2016] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To evaluate a range of mechanical parameters of composite resins and compare the data to the frequency of fractures and wear in clinical studies. METHODS Based on a search of PubMed and SCOPUS, clinical studies on posterior composite restorations were investigated with regard to bias by two independent reviewers using Cochrane Collaboration's tool for assessing risk of bias in randomized trials. The target variables were chipping and/or fracture, loss of anatomical form (wear) and a combination of both (summary clinical index). These outcomes were modelled by time and material in a linear mixed effect model including random study and experiment effects. The laboratory data from one test institute were used: flexural strength, flexural modulus, compressive strength, and fracture toughness (all after 24-h storage in distilled water). For some materials flexural strength data after aging in water/saliva/ethanol were available. Besides calculating correlations between clinical and laboratory outcomes, we explored whether a model including a laboratory predictor dichotomized at a cut-off value better predicted a clinical outcome than a linear model. RESULTS A total of 74 clinical experiments from 45 studies were included involving 31 materials for which laboratory data were also available. A weak positive correlation between fracture toughness and clinical fractures was found (Spearman rho=0.34, p=0.11) in addition to a moderate and statistically significant correlation between flexural strength and clinical wear (Spearman rho=0.46, p=0.01). When excluding those studies with "high" risk of bias (n=18), the correlations were generally weaker with no statistically significant correlation. For aging in ethanol, a very strong correlation was found between flexural strength decrease and clinical index, but this finding was based on only 7 materials (Spearman rho=0.96, p=0.0001). Prediction was not consistently improved with cutoff values. SIGNIFICANCE Correlations between clinical and laboratory outcomes were moderately positive with few significant results, fracture toughness being correlated with clinical fractures and flexural strength with clinical wear. Whether artificial aging enhances the prognostic value needs further investigations.
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Affiliation(s)
| | - Nicoleta Ilie
- Department of Operative Dentistry and Periodontology, University Hospital, Ludwig-Maximilian-University, Munich, Germany
| | - Reinhard Hickel
- Department of Operative Dentistry and Periodontology, University Hospital, Ludwig-Maximilian-University, Munich, Germany
| | - Alessandra Reis
- Department of Restorative Dentistry, State University of Ponta Grossa, Brazil
| | | | - Valentin Rousson
- Division of Biostatistics, Institute for Social and Preventive Medicine, University Hospital Lausanne, Switzerland
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