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Effect of Light Curing Distance on Microhardness Profiles of Bulk-Fill Resin Composites. Polymers (Basel) 2022; 14:polym14030528. [PMID: 35160517 PMCID: PMC8839654 DOI: 10.3390/polym14030528] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 11/16/2022] Open
Abstract
Bulk-fill (BF) dental resin composites are made to be polymerized in increments of up to 5 mm rather than the 2 mm increment recommended for conventional composites. This project aimed to determine microhardness (MH) profiles of BF resin composites at different depths and varying light cure (LC) distances from the light source in an attempt to mimic varying clinical situations. Forty-eight cylindrical specimens (4 mm diameter and 6 mm height) were prepared from 3 BF composites: Tetric N-Ceram Bulk-Fill (TBF), Filtek One Bulk-Fill (FBF), and Sonic-Fill 2 (SF2). Four different distances (0, 2, 4, and 6 mm) from the LC unit were investigated. Vickers MH was measured at the top and bottom of the samples and at every 1 mm, by creating 3 indentations at each depth. The bottom-top microhardness ratio (MHR) and percentage reduction in MHR were also measured. Data was analyzed using mixed-model repeated-measure ANOVA at 0.05 significance level. The main variables effects “material, LC distance, and depth” were significant (p < 0.001). Increasing LC distance and the depth of the tested BF significantly affected Vickers MH and MHR. None of the tested BF materials had sufficient MHR at the depths of 4–6 mm. SF2 showed the least MHR reduction.
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Marovic D, Haugen HJ, Negovetic Mandic V, Par M, Zheng K, Tarle Z, Boccaccini AR. Incorporation of Copper-Doped Mesoporous Bioactive Glass Nanospheres in Experimental Dental Composites: Chemical and Mechanical Characterization. MATERIALS (BASEL, SWITZERLAND) 2021; 14:2611. [PMID: 34067788 PMCID: PMC8156461 DOI: 10.3390/ma14102611] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/06/2021] [Accepted: 05/14/2021] [Indexed: 12/03/2022]
Abstract
Experimental dental resin composites incorporating copper-doped mesoporous bioactive glass nanospheres (Cu-MBGN) were designed to impart antibacterial and remineralizing properties. The study evaluated the influence of Cu-MBGN on the mechanical properties and photopolymerization of resin composites. Cu-MBGN were synthesized using a microemulsion-assisted sol-gel method. Increasing amounts of Cu-MBGN (0, 1, 5, and 10 wt %) were added to the organic polymer matrix with inert glass micro- and nanofillers while maintaining a constant resin/filler ratio. Six tests were performed: X-ray diffraction, scanning electron microscopy, flexural strength (FS), flexural modulus (FM), Vickers microhardness (MH), and degree of conversion (DC). FS and MH of Cu-MBGN composites with silica fillers showed no deterioration with aging, with statistically similar results at 1 and 28 days. FM was not influenced by the addition of Cu-MBGN but was reduced for all tested materials after 28 days. The specimens with 1 and 5% Cu-MBGN had the highest FS, FM, MH, and DC values at 28 days, while controls with 45S5 bioactive glass had the lowest FM, FS, and MH. DC was high for all materials (83.7-93.0%). Cu-MBGN composites with silica have a potential for clinical implementation due to high DC and good mechanical properties with adequate resistance to aging.
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Affiliation(s)
- Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (M.P.); (Z.T.)
| | - Håvard J. Haugen
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, 0455 Oslo, Norway;
| | - Visnja Negovetic Mandic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (M.P.); (Z.T.)
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (M.P.); (Z.T.)
| | - Kai Zheng
- Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen, Germany; (K.Z.); (A.R.B.)
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (M.P.); (Z.T.)
| | - Aldo R. Boccaccini
- Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen, Germany; (K.Z.); (A.R.B.)
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Aung SZ, Takagaki T, Ikeda M, Nozaki K, Burrow MF, Abdou A, Nikaido T, Tagami J. The effect of different light curing units on Vickers microhardness and degree of conversion of flowable resin composites. Dent Mater J 2020; 40:44-51. [PMID: 32848103 DOI: 10.4012/dmj.2019-353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study aimed to assess the influence of different light curing units (LCUs) on the polymerization of various flowable resin composites. Three LCUs (Optilux 501, Elipar™ DeepCure-L LED and Bluephase®20i) and eight flowable resin composites: MI FIL Flow, Estelite Flow Quick, Estelite Universal Flow (medium), Estelite Universal Flow (super low), Beautifil Flow Plus, Clearfil Majesty ES Flow, Filtek Supreme Ultra flowable and TetricEvo Flow were tested. For Vickers microhardness (VHN) test and degree of conversion (DC), specimens were prepared and polymerized for 20 s. VHN test was performed at top surfaces (3 indentations) and DC for each specimen was measured using Fourier transform infrared (FT-IR) spectroscopy after 24 h dry storage in dark at 37˚C. The data were analyzed with 2-way ANOVA and t-test with Bonferroni correction. DC and hardness values showed a relationship between materials and LCUs. The curing efficacy of LCU type may depend on the material composition.
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Affiliation(s)
- Swe Zin Aung
- Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Tomohiro Takagaki
- Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Department of Operative Dentistry, Division of Oral Functional Sciences and Rehabilitation, School of Dentistry, Asahi University
| | - Masaomi Ikeda
- Oral Prosthetic Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Kosuke Nozaki
- Department of Biofunction Research, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental Universit
| | - Michael F Burrow
- Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital
| | - Ahmed Abdou
- Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Toru Nikaido
- Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Department of Operative Dentistry, Division of Oral Functional Sciences and Rehabilitation, School of Dentistry, Asahi University
| | - Junji Tagami
- Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
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Xue R, Mao J, Zhao H, Yang C, Gao H, Xu J, Jiang M. Effect of nano silicon dioxide on the structure and properties of FeCl
3
‐doped polyvinyl alcohol photopolymer film. J Appl Polym Sci 2019. [DOI: 10.1002/app.47702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Runping Xue
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
| | - Jianzhao Mao
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
| | - Hong Zhao
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
| | - Chen Yang
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
| | - Huihui Gao
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
| | - Jianjun Xu
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
| | - Mengjin Jiang
- The State Key Laboratory of Polymer Materials and EngineeringCollege of Polymer Science and Engineering, Sichuan University Chengdu 610065 China
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Effect of the Time of Salivary Contamination during Light Curing on Degree of Conversion and Microhardness of a Restorative Composite Resin. Biomimetics (Basel) 2018; 3:biomimetics3030023. [PMID: 31105245 PMCID: PMC6352669 DOI: 10.3390/biomimetics3030023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 08/16/2018] [Accepted: 08/18/2018] [Indexed: 11/21/2022] Open
Abstract
Saliva contamination is a major clinical problem in restorative procedures. The purpose of this study was to evaluate the effect of the time of salivary contamination during light curing on the degree of conversion and the microhardness of a restorative composite resin. Eight groups of 10 samples for measuring the microhardness and eight groups of 5 samples for evaluating the degree of conversion were prepared. The samples of each group were contaminated with human saliva at a certain time. The first group (T0) was contaminated before light curing. The specimens in groups T2–T30 were contaminated at 2, 5, 10, 15, 20 and 30 s after the start of light curing, respectively. The samples of group T40 were contaminated after light curing. The degree of conversion and the microhardness of the specimens were measured by Fourier transform infrared (FTIR) spectroscopy and Vickers hardness testing techniques, respectively. The results of this study revealed that there were no significant differences between the groups in terms of the degree of conversion of the composite resin. Consistent with the findings for the degree of conversion, significant differences in the microhardness between the groups were not found. In conclusion, from a clinical point of view, the results of our study showed that the time of salivary contamination (before, during or after light curing of composite resin) has no significant effect on the polymerization (degree of conversion) and one of the important mechanical properties of dental composite resins (microhardness).
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Kumar SR, Patnaik A, Bhat I. Wear behavior of light-cured dental composite reinforced with silane-treated nanosilica filler. POLYM ADVAN TECHNOL 2018. [DOI: 10.1002/pat.4251] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Amar Patnaik
- Mechanical Engineering Department; MNIT Jaipur; Jaipur India
| | - I.K. Bhat
- Applied Mechanics Department; MNNIT Allahabad; Allahabad India
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Marovic D, Tarle Z, Hiller KA, Müller R, Rosentritt M, Skrtic D, Schmalz G. Reinforcement of experimental composite materials based on amorphous calcium phosphate with inert fillers. Dent Mater 2014; 30:1052-60. [PMID: 25015877 DOI: 10.1016/j.dental.2014.06.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 11/08/2013] [Accepted: 06/05/2014] [Indexed: 11/17/2022]
Abstract
OBJECTIVES The aim of this study was to examine the influence of the addition of glass fillers with different sizes and degrees of silanization percentages to remineralizing composite materials based on amorphous calcium phosphate (ACP). METHODS Four different materials were tested in this study. Three ACP based materials: 0-ACP (40 wt% ACP, 60 wt% resin), Ba-ACP (40 wt% ACP, 50 wt% resin, 10 wt% barium-glass) and Sr-ACP (40 wt% ACP, 50 wt% resin, 10 wt% strontium-glass) were compared to the control material, resin modified glass ionomer (Fuji II LC capsule, GC, Japan). The fillers and composites were characterized using scanning electron microscopy. Flexural strength and modulus were determined using a three-point bending test. Calcium and phosphate ion release from ACP based composites was measured using inductively coupled plasma atomic emission spectroscopy. RESULTS The addition of barium-glass fillers (35.4 (29.1-42.1) MPa) (median (25-75%)) had improved the flexural strength in comparison to the 0-ACP (24.8 (20.8-36.9) MPa) and glass ionomer control (33.1 (29.7-36.2) MPa). The admixture of strontium-glass (20.3 (19.5-22.2) MPa) did not have any effect on flexural strength, but significantly improved its flexural modulus (6.4 (4.8-6.9) GPa) in comparison to 0-ACP (3.9 (3.4-4.1) GPa) and Ba-ACP (4.6 (4.2-6.9) GPa). Ion release kinetics was not affected by the addition of inert fillers to the ACP composites. SIGNIFICANCE Incorporation of barium-glass fillers to the composition of ACP composites contributed to the improvement of flexural strength and modulus, with no adverse influence on ion release profiles.
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Affiliation(s)
- Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Croatia.
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Croatia
| | - Karl-Anton Hiller
- Department of Operative Dentistry and Periodontology, University Hospital Regensburg, University of Regensburg, Germany
| | - Rainer Müller
- Institute of Physical and Theoretical Chemistry, University of Regensburg, Germany
| | - Martin Rosentritt
- Department of Prosthodontics, University Hospital Regensburg, University of Regensburg, Germany
| | - Drago Skrtic
- Dr. Anthony Volpe Research Center, ADA Foundation, Gaithersburg, MD, USA
| | - Gottfried Schmalz
- Department of Operative Dentistry and Periodontology, University Hospital Regensburg, University of Regensburg, Germany
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Alsharif SO, Bin Md Akil H, Abbas Abd El-Aziz N, Arifin Bin Ahmad Z. Effect of alumina particles loading on the mechanical properties of light-cured dental resin composites. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.matdes.2013.07.069] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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9
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An In vitro Evaluation of Flexural Bond Strength of Indirect Composites Fused to Metal. J Indian Prosthodont Soc 2014; 13:122-7. [PMID: 24431721 DOI: 10.1007/s13191-013-0271-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Accepted: 03/06/2013] [Indexed: 10/27/2022] Open
Abstract
With the advent of newer indirect composite resin materials for crown and bridge prosthesis, it has become imperative to evaluate their strength to serve as long term replacements as a substitute to metal ceramic restorations. This study aimed to evaluate and compare the flexural bond strength of three composite resin veneering material to metal, cured by different methods. Specimen were fabricated with pattern resin by duplicating it with machined metal die and divided into three groups. Three composite resin materials were used in this study. Group (A) received Adoro, Group (B) received Targis and Group (C) received Tescera. The bond strength of all specimens was tested with Lloyd's universal testing machine under three point loading. The highest values for fracture resistance were displayed by light, heat and pressure cured composites followed by composites cured using a temperature of 104 °C and composites with curing temperature of 95 °C. The results indicate that there is a significant difference between the three groups, with the Tescera group specimens exhibiting the highest flexural bond strength. Of the other two groups, Adoro group exhibited higher flexural bond strength than Targis group. The results of this study suggest that Tescera group with curing temperature of 130 °C and pressure of 80 Psi, cured with metal halide unit exhibited the highest flexural bond strength when compared to Adoro and Targis groups.
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11
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Archegas LRP, de Menezes Caldas DB, Rached RN, Soares P, Souza EM. Effect of Ceramic Veneer Opacity and Exposure Time on the Polymerization Efficiency of Resin Cements. Oper Dent 2012; 37:281-9. [DOI: 10.2341/11-134-l] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
The objective of this study was to determine the degree of conversion (DC), hardness (H), and modulus of elasticity (E) of a dual-cured resin cement, a light-cured resin cement, and a flowable resin cured through opaque or translucent ceramic with different exposure times. RelyX ARC (dual), RelyX Veneer (light-cured), and Filtek Z350 Flow resin specimens 0.5 mm thick were cured for 40, 80, and 120 seconds through 1-mm thick translucent or opaque feldspathic ceramic disks (n=10). The specimens were stored at 37°C for 24 hours. Half of each specimen was used to test the DC and the other half to test H and E. The DC was determined in a Fourier transform infrared spectrometer in absorbance mode at peaks of 1638 cm−1 and 1610 cm−1. H and E were determined using nanoindentation with one loading cycle and a maximum load of 400 mN. The data were analyzed with three-way analysis of variance (ANOVA), the Games-Howell test, and the Pearson correlation test (α=0.05). Statistically significant differences were found for all three factors (material, opacity, and exposure time), as well as interaction between them. The opaque ceramic resulted in lower DC, H, and E than the translucent ceramic for an exposure time of 40 seconds. An exposure time of 120 seconds resulted in a similar DC for all materials, irrespective of the opacity of the ceramic. Materials cured for 120 seconds had higher H and E than those cured for 40 seconds. The exposure time and opacity of the ceramic exerted an influence on the DC, H, and E of the materials evaluated.
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Munchow EA, Correa MB, Ogliari FA, Piva E, Zanchi CH. Correlation between surface roughness and microhardness of experimental composites with varying filler concentration. J Contemp Dent Pract 2012; 13:299-304. [PMID: 22918000 DOI: 10.5005/jp-journals-10024-1141] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
AIM The purpose of this study was to investigate the influence of the surface roughness on the surface microhardness of experimental composites with varying filler concentration. MATERIALS AND METHODS Experimental resin composites were formulated by mixing Bis-GMA and TEGDMA in a 50/50% weight ratio and CQ/EDAB were added to make the material photosensitive. Silanized glass particles were incorporated in the resin blend in two concentrations: C50 with 50% and C75 with 75% in weight ratio. The surface roughness and the surface microhardness measurements were determined after every three finishing procedures with #280-, #600- and #1200-grit wet sandpapers, respectively. The data were analyzed statistically by Two Way ANOVA and Tukey's test, and comparisons were conducted using the Spearman's correlation test (p > 0.05). RESULTS The surface roughness and surface microhardness were negatively associated (r = - 0.68) and the finishing procedures of both composites resulted in harder and smoother surfaces than the initial ones. Additionally, in a smooth circumstance, the higher content of fillers has not resulted in a composite with better microhardness and smoothness. CONCLUSION Finishing procedures decreased the surface roughness and consequently improved the surface microhardness of the composites evaluated. CLINICAL SIGNIFICANCE Finishing and polishing procedures are effectives in reducing the surface roughness amplitude of composite materials and in improving their surface microhardness. Thus a microhardness test and any hardness evaluation must be conducted only after a properly finished and polished surface is achieved.
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Affiliation(s)
- Eliseu Aldrighi Munchow
- PhD Student, Department of Operative Dentistry, School of Dentistry Federal University of Pelotas, Pelotas, RS, Brazil.
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Nandini S. Indirect resin composites. J Conserv Dent 2010; 13:184-94. [PMID: 21217945 PMCID: PMC3010022 DOI: 10.4103/0972-0707.73377] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 09/25/2010] [Accepted: 09/28/2010] [Indexed: 11/17/2022] Open
Abstract
Aesthetic dentistry continues to evolve through innovations in bonding agents, restorative materials, and conservative preparation techniques. The use of direct composite restoration in posterior teeth is limited to relatively small cavities due to polymerization stresses. Indirect composites offer an esthetic alternative to ceramics for posterior teeth. This review article focuses on the material aspect of the newer generation of composites. This review was based on a PubMed database search which we limited to peer-reviewed articles in English that were published between 1990 and 2010 in dental journals. The key words used were 'indirect resin composites,' composite inlays,' and 'fiber-reinforced composites.'
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Affiliation(s)
- Suresh Nandini
- Department of Conservative Dentistry, Meenakshi Ammal Dental College, Chennai - 600 095, India
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Pereira SG, Fulgêncio R, Nunes TG, Toledano M, Osorio R, Carvalho RM. Effect of curing protocol on the polymerization of dual-cured resin cements. Dent Mater 2010; 26:710-8. [DOI: 10.1016/j.dental.2010.03.016] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Revised: 12/15/2009] [Accepted: 03/09/2010] [Indexed: 10/19/2022]
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Monte Alto RV, Guimarães JGA, Poskus LT, da Silva EM. Depth of cure of dental composites submitted to different light-curing modes. J Appl Oral Sci 2009; 14:71-6. [PMID: 19089034 PMCID: PMC4327445 DOI: 10.1590/s1678-77572006000200002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Accepted: 12/21/2005] [Indexed: 11/21/2022] Open
Abstract
Objective: This study evaluated the depth of cure of five dental composites submitted to different light-curing modes. Material and Methods: Canal-shaped cavities with 5mm of length were prepared on the buccal surfaces of extracted third molars, and restored using P-60, A-110, Admira, Z-250 and Supreme resin composites. Materials were light-cured from the top, according to three modes (Group 1- Conventional (C): 500 mW/cm2/ 40 s; Group 2 – Soft-Start (SS):250 mW/cm2/ 20 s + 500 mW/cm2/ 20 s + 500 mW/cm2/ 10 s and Group 3 – LED: 250 mW/cm2/ 40 s). After that, cavity longitudinal surfaces were polished and marked with a millimeter scale of 4mm of length. Depth of cure was evaluated by means of Knoop hardness number (KHN), so that five indentations were performed at each millimeter. Original data were submitted to three-way ANOVA and Fisher's LSD test (α = 0.01). Results: All materials presented a significant reduction on KHN from first to third millimeter. Regarding depth of cure, the results obtained for Conventional and Soft-Start modes were similar, but statistically superiors to those found for group 3 (LED). Conclusion: This performance may be related to the differences among energy densities obtained with different light-curing modes.
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Affiliation(s)
- Raphael Vieira Monte Alto
- Department of Restorative Dentistry, School Of Dentistry, Federal Fluminense University, Ingá, Niterói, RJ
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Anfe TEDA, Caneppele TMF, Agra CM, Vieira GF. Microhardness assessment of different commercial brands of resin composites with different degrees of translucence. Braz Oral Res 2008; 22:358-63. [PMID: 19148393 DOI: 10.1590/s1806-83242008000400013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Accepted: 10/08/2007] [Indexed: 11/22/2022] Open
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Lloret PR, Rode KM, Turbino ML. Dentine bond strength of a composite resin polymerized with conventional light and argon laser. Braz Oral Res 2005; 18:271-5. [PMID: 15619884 DOI: 10.1590/s1806-83242004000300017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
The use of argon laser (488 nm) has been suggested as a new alternative for polymerizing adhesive materials. This study aimed to evaluate the tensile bond strength of a microfilled composite (A110, 3M) inserted by incremental technique (3 increments of 1 mm) and by single increment (3 mm) polymerized by argon laser for 10, 20 and 30 seconds and halogen light for 40 seconds. Eighty (8 groups of 10 teeth) freshly extracted bovine teeth were stored in a freezer in distilled water for one week. The crowns were cross-sectioned from the roots. Pulpectomy was performed and the pulp chambers were sealed with wax. The buccal surfaces of the teeth were ground with wet sandpaper (grains: 120, 400, and 600) to expose the surface dentin, and the teeth were then included in acrylic resin. A metal device was used to fix each sample and a black propylene matrix25 (3 mm high with an internal millimetric delimitation) was used to insert the material according to the groups studied. The polymerization intervals were of 10, 20 and 30 seconds for the laser polymerization and 40 seconds for the conventional polymerization. Tensile tests were performed by a Universal Testing Machine 4442 (Instron) at a speed of 0.5 mm/min and 500 N load. According to the methodology used, the incremental technique increased bond strength values. There was no difference between the studied polymerization techniques when resin was filled in 3 increments.
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