1
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Chen WC, Lai TW, Li CL, Chen TYF, Chang CH, Chuang SF. Assessments of polymerization shrinkage by optical coherence tomography-based digital image correlation analysis-Part II: Effects of restorative composites. Dent Mater 2024; 40:1064-1071. [PMID: 38777732 DOI: 10.1016/j.dental.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 04/27/2024] [Accepted: 05/03/2024] [Indexed: 05/25/2024]
Abstract
OBJECTIVES To examine the polymerization shrinkage of different resin-based composite (RBC) restorations using optical coherence tomography (OCT) image-based digital image correlation (DIC) analysis. METHODS The refractive index (RI) of three RBCs, Filtek Z350XT (Z350), Z350Flowable (Z350F), and BulkFill Posterior (Bulkfill), was measured before and after polymerization to calibrate their axial dimensions under OCT. Class I cavities were prepared in bovine incisors and individually filled with these RBCs under nonbonded and bonded conditions. A series of OCT images of these restorations were captured during 20-s light polymerization and then input into DIC software to analyze their shrinkage behaviors. The interfacial adaptation was also examined using these OCT images. RESULTS The RI of the three composites ranged from 1.52 to 1.53, and photopolymerization caused neglectable increases in the RI values. For nonbonded restorations, Z350F showed maximal vertical displacements on the top surfaces (-16.75 µm), followed by Bulkfill (-8.81 µm) and Z350 (-5.97 µm). In their bonded conditions, all showed increased displacements. High variations were observed in displacement measurements on the bottom surfaces. In the temporal analysis, the shrinkage of nonbonded Z350F and Bulkfill decelerated after 6-10 s. However, Z350 showed a rebounding upward displacement after 8.2 s. Significant interfacial gaps were found in nonbonded Z350 and Z350F restorations. SIGNIFICANCE The novel OCT image-based DIC analysis provided a comprehensive examination of the shrinkage behaviors and debonding of the composite restorations throughout the polymerization process. The flowable composite showed the highest shrinkage displacements. Changes in the shrinkage direction may occur in nonbonded conventional composite restorations.
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Affiliation(s)
- Wei-Chi Chen
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Dentistry, Sin-Lau Hospital, Tainan, Taiwan
| | - Ting-Weng Lai
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Stomatology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Chia-Ling Li
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Terry Yuan-Fang Chen
- Department of Mechanical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Chih-Han Chang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Shu-Fen Chuang
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Stomatology, National Cheng Kung University Hospital, Tainan, Taiwan.
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2
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de Deus RA, Oliveira L, Braga S, Ribeiro M, Price RB, Núñez A, Loguercio AD, Soares CJ. Effect of Radiant Exposure on the Physical and Mechanical Properties of 10 Flowable and High-viscosity Bulk-fill Resin Composites. Oper Dent 2024; 49:136-156. [PMID: 38349819 DOI: 10.2341/23-025-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: 11/27/2023] [Indexed: 02/15/2024]
Abstract
OBJECTIVES To evaluate the effect of the different radiant exposures from a multipeak light curing unit on the physical and mechanical properties of flowable and high-viscosity bulk-fill resin-based composites (RBC). METHODS Five flowable bulk-fill RBCs (Tetric N-Flow Bulk-fill, Ivoclar Vivadent; Filtek Bulk Fill Flow, 3M Oral Care; Opus Bulk Fill Flow APS, FGM; Admira Fusion x-base, Voco and; and SDR Plus Bulk Fill Flowable, Dentsply Sirona) and five high-viscosity bulk-fill RBCs (Tetric N-Ceram Bulk-fill, Ivoclar Vivadent; Filtek One Bulk Fill, 3M Oral Care; Opus Bulk Fill APS, FGM; Admira Fusion x-tra, Voco; and SonicFill 2, Kerr) were photo-cured using a VALO Cordless light (Ultradent) for 10, 20, and 40 seconds at an irradiance of 1200, 800, or 400 mW/cm2, resulting in the delivery of 4, 8, 12, 16, 24, 32, or 48 J/cm2. Post-gel shrinkage (Shr) was calculated using strain-gauge test. The degree of conversion (DC, %) was calculated using FTIR. Knoop hardness (KH, N/mm2) and elastic modulus (E, MPa) were measured at the top and bottom surfaces. Logarithmic regressions between the radiant exposures and mechanical properties were calculated. Radiodensity was calculated using digital radiographs. Data of Shr and radiodensity were analyzed using two-way analysis of variance (ANOVA), and the DC, KH, and E data were analyzed with two-way ANOVA using split-plot repeated measurement tests followed by the Tukey test (a = 0.05). RESULTS Delivering higher radiant exposures produced higher Shr values (p<0.001) and higher DC values (R2=0.808-0.922; R2=0.648-0.914, p<0.001), KH (R2=0.707-0.952; R2=0.738-0.919; p<0.001), and E (R2=0.501-0.925; R2=0.823-0.919; p<0.001) values for the flowable and high-viscosity RBCs respectively. Lower KH, E and Shr were observed for the flowable bulk-fill RBCs. All bulk-fill RBCs had a radiopacity level greater than the 4-mm thick aluminum step wedge. The radiant exposure did not affect the radiopacity. CONCLUSION The Shr, DC, KH, and E values were highly correlated to the radiant exposure delivered to the RBCs. The combination of the higher irradiance for longer exposure time that resulted in radiant exposure between 24 J/cm2 to 48 J/cm2 produced better results than delivering 400 mW/cm2 for 40 s (16 J/cm2), and 800 mW/cm2 for 20 seconds (16 J/cm2) or 1200 mW/cm2 for 10 seconds (12 J/cm2). All the bulk-fill RBCs were sufficiently radiopaque compared to 4 mm of aluminum.
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Affiliation(s)
- R A de Deus
- Raissa Albuquerque de Deus, DDS, MSc, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Lrs Oliveira
- Lais Rani Sales Oliveira, DDS, MSc, PhD, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Ssl Braga
- Stella Sueli Lourenço Braga, DDS, MSc, PhD, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Mth Ribeiro
- Maria Tereza Hordones Ribeiro, DDS, MSc, PhD student, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - R B Price
- Richard Bengt Price, DDS, MSc, PhD, Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - A Núñez
- Alejandra Núñez, DDS, MSc, PhD student, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR, Brazil
| | - A D Loguercio
- Alessandro Dourado Loguercio, DDS, MSc, PhD, School of Dentistry, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR, Brazil
| | - C J Soares
- *Carlos José Soares, DDS, MS, PhD, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
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3
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Raza MA, Khan JA, Akhtar H, Farooqui WA, Faraz H, Hasan A. Comparison of two composite resin materials for splinting of dental luxation injuries: A double blind randomized controlled trial. Dent Traumatol 2024; 40:44-53. [PMID: 37615239 DOI: 10.1111/edt.12883] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/11/2023] [Accepted: 08/09/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND/AIM Luxation is a common traumatic dental injury treated with a wire composite (WC) splint. However, bulk-fill flowable composite and conventional packable composite have not been compared for retaining these splints. Therefore, the objectives of this randomized controlled trial were (1) to compare retention of WC splints, and (2) to compare adhesive point dimension, application and removal time, and effect on tooth mobility between the two WC splints. MATERIALS AND METHODS In this parallel group, non-inferiority double blind randomized controlled trial, a total of 90 patients, aged 16-50 years participated. They were randomly allocated into two groups, the packable composite group (PC) n = 45 and the bulk-fill flowable composite group (BF-FC) n = 45 by lottery method. Following measurements were taken at the splint application appointment. Horizontal tooth mobility measured via Periotest, splint application time, and frontal images of splinted teeth to measure the percentage composite adhesive point area. After 2 weeks, splints were visually inspected for retention, whereas mobility and removal times were also recorded. Statistically, comparisons were made using independent samples sample T-test, Fisher's exact test, and Mann-Whitney U at p ≤ .05. RESULTS A total of 88 patients with 156 luxated teeth completed the trial, as two patients were lost to follow-up. Two patients in the PC group reported with completely de-bonded splints while none de-bonded in the BF-FC group. Both groups were similar in terms of splint retention (p = .352), reduction of mobility (p = .426), and splint removal times (p = .372). The BF-FC group performed significantly better in adhesive point dimension percentages (p < .001) and splint application time (p < .001). CONCLUSION Both groups were comparable in most parameters of the study. However, for BF-FC group application time and adhesive point dimension were significantly less.
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Affiliation(s)
- Misbah Ali Raza
- Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences Baba-e-Urdu Road Karachi, Karachi, Pakistan
| | - Javeria Ali Khan
- Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences Baba-e-Urdu Road Karachi, Karachi, Pakistan
| | - Hira Akhtar
- Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences Baba-e-Urdu Road Karachi, Karachi, Pakistan
| | | | - Hira Faraz
- Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences Baba-e-Urdu Road Karachi, Karachi, Pakistan
| | - Arshad Hasan
- Department of Operative Dentistry, Dow Dental College, Dow University of Health Sciences Baba-e-Urdu Road Karachi, Karachi, Pakistan
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4
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Crack propensity of different direct restorative procedures in deep MOD cavities. Clin Oral Investig 2023; 27:2003-2011. [PMID: 36814029 DOI: 10.1007/s00784-023-04927-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Accepted: 02/16/2023] [Indexed: 02/24/2023]
Abstract
OBJECTIVE The purpose was to evaluate the crack formation associated with different direct restorative procedures of the utilized resin composites (RC) right after and 1 week later of the restoration. MATERIALS AND METHODS Eighty intact, crack-free third molars with standard MOD cavities were included in this in vitro study and randomly divided into four groups of 20 each. After adhesive treatment, the cavities were restored either with bulk (group 1) or layered (group 2) short-fiber-reinforced resin composites (SFRC); bulk-fill RC (group 3); and layered conventional RC (control). Right after the polymerization and a week later, crack evaluation on the outer surface of the remaining cavity walls was performed with a transillumination method utilizing the D-Light Pro (GC Europe) with the "detection mode." Between- and within-groups comparisons Kruskal-Wallis and Wilcoxon tests were used, respectively. RESULTS Post-polymerization crack evaluation showed significantly lower crack formation in SFRC groups compared to the control (p<0.001). There was no significant difference within SFRC groups and non-SFRC groups (p=1.00 and p=0.11, respectively). Within group comparison revealed significantly higher number of cracks in all groups after 1 week (p≤0.001), however, only the control group differed significantly from all the other groups (p≤0.003). CONCLUSIONS Post-polymerization shrinkage induced further crack formation in the tooth 1 week after the restoration. SFRC was less prone to shrinkage-related crack formation during the restorative procedure; however, after 1 week, besides SFRC, bulk-fill RC also showed less prone to polymerization shrinkage-related crack formation than layered composite fillings. CLINICAL RELEVANCE SRFC can decrease the shrinkage stress-induced crack formation in MOD cavities.
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5
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Steffen T, Par M, Attin T, Tauböck TT. Effect of Fast High-Irradiance Photo-Polymerization of Resin Composites on the Dentin Bond Strength. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7467. [PMID: 36363058 PMCID: PMC9655088 DOI: 10.3390/ma15217467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
This study investigated the influence of conventional (10 s at 1160 mW/cm2) and fast high-irradiance (3 s at 2850 mW/cm2) light curing on the micro-tensile bond strength (μTBS) of bulk-fill resin composites bonded to human dentin. Sixty-four extracted human molars were ground to dentin and randomly assigned into eight groups (n = 8 per group). After application of a three-step adhesive system (Optibond FL), four different bulk-fill composites (two sculptable and two flowable composites) were placed. Of these, one sculptable (Tetric PowerFill) and one flowable (Tetric PowerFlow) composite were specifically developed for fast high-irradiance light curing. Each composite was polymerized with the conventional or the fast high-irradiance light-curing protocol. The specimens were cut into dentin-composite sticks, μTBS was determined and failure modes were analyzed. Statistical analysis was performed using t-test for independent observations and one-way ANOVA. A statistical difference between the curing protocols was only found for Tetric PowerFlow, where the conventional protocol (23.8 ± 4.2 MPa) led to significantly higher values than the fast high-irradiance light-curing protocol (18.7 ± 3.7 MPa). All other composite materials showed statistically similar values for both polymerization protocols. In conclusion, the use of fast high-irradiation light curing has no negative influence on the μTBS of the investigated high-viscosity bulk-fill composites. However, it may reduce the dentin bond strength of flowable bulk-fill composite.
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Affiliation(s)
- Tobias Steffen
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Thomas Attin
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Tobias T. Tauböck
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
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6
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Fracture Resistance and Microleakage around Direct Restorations in High C-Factor Cavities. Polymers (Basel) 2022; 14:polym14173463. [PMID: 36080538 PMCID: PMC9460406 DOI: 10.3390/polym14173463] [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: 07/30/2022] [Revised: 08/20/2022] [Accepted: 08/21/2022] [Indexed: 11/29/2022] Open
Abstract
The aim of this research was to evaluate the mechanical impact of different direct restorations in terms of fracture resistance, and subsequent fracture pattern, in occlusal high C-factor cavities. Furthermore, the adaptation of different direct restorations in the form of gap formation was also evaluated. Seventy-two intact mandibular molars were collected and randomly distributed into three groups (n = 24). Class I occlusal cavities with standardized dimensions were prepared in all specimens. After adhesive treatment, the cavities were restored with direct restorations utilizing three different materials. Group 1: layered conventional packable resin composite (Filtek Ultimate), Group 2: bulk-fill resin composite (SDR), Group 3: bulk-fill short fibre-reinforced composite (SFRC; everX Posterior) covered with packable composite occlusally. Half of the restored specimens underwent static load-to fracture testing (n = 12/group), while the rest underwent sectioning and staining for microleakage evaluation and gap formation analysis. Fracture patterns were evaluated visually among the mechanically tested specimens. The layered composite restoration (Group 1) showed significantly lower fracture resistance compared to the bulk fill groups (Group 2, p = 0.005, Group 3, p = 0.008), while there was no difference in fracture resistance between the other groups. In terms of gap formation values, the layered composite restoration (Group 1) produced significantly higher gap formation compared to the bulk-fill groups (Group 2, p = 0.000, Group 3, p = 0.000). Regarding the fracture pattern, SFRC (Group 3) produced the highest number, while SDR (Group 2) produced the lowest number of repairable fractures. The use of bulk-fill resin composite (fibre or non-fibre-reinforced) for occlusal direct restorations in high C-factor cavities showed promising achievements regarding both fracture resistance and microleakage. Furthermore, the use of short fibre-reinforced bulk-fill composite can also improve the fracture pattern of the restoration-tooth unit. Bulk-fill materials provide a simple and effective solution for restoring and reinforcing high C-factor occlusal cavities.
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7
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Peskersoy C, Sahan HM. Finite element analysis and nanomechanical properties of composite and ceramic dental onlays. Comput Methods Biomech Biomed Engin 2022; 25:1649-1661. [PMID: 35098830 DOI: 10.1080/10255842.2022.2032004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The aim is to evaluate the mechanical properties of the composite and ceramic based indirect restorative materials used in dental treatments with scanning nanoindentation test (NT). Finite element analysis (FEA) was applied to investigate the stress distribution. Four hybrid composite materials; Indirect resin composite (IRC), Resin nanoceramic (RNC), Polymer infiltrated ceramic (PIC) and Zirconia-reinforced lithium-di-silicate (ZRC) were divided into two subgroups for NT (n = 20) and fracture test (n = 40). Statistical analyses were performed with independent t-test, ANOVA and post-hoc Tukey tests (p ≤ 0.05). The highest hardness, elasticity and fracture toughness were observed in ZRC (p = 0.001). Frequency of vertical root fractures in RNC and IRC were statistically lower than ZRC (p = 0.032). Reinforced CAD-CAM ceramics revealed higher mechanical properties compared with IRC materials. The FEA model for fracture mechanism of RNC demonstrated lowest stress values and uniform stress distribution amongst all groups, while ZRC and PIC presented the highest fracture toughness.
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Affiliation(s)
- Cem Peskersoy
- Faculty of Dentistry, Ege University, Izmir, Izmir, Turkey
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8
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Oliveira L, Melo C, Cavalcanti K, Soares P, Cardenas A, Soares CJ. Effects of Adjacent Tooth Type and Occlusal Fatigue on Proximal Contact Force of Posterior Bulk Fill and Incremental Resin Composite Restoration. Oper Dent 2022; 47:64-75. [PMID: 35090036 DOI: 10.2341/20-019-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: 02/13/2021] [Indexed: 11/23/2022]
Abstract
OBJECTIVES To measure the proximal contact force in newtons (N) between incremental and bulk fill class II resin composite restorations and implant molar teeth or adjacent premolar teeth with simulated periodontal ligament. METHODS The model used was created with a typodont first molar tooth with two bilateral occlusal-proximal class II cavities, an adjacent tooth simulating an implanted molar tooth (Titamax CM, Neodent, Curtiba, PR, Brazil) and a premolar with simulated periodontal ligament. Two resin composite restorative techniques were used: Inc-Z350XT, (Filtek Z350, 3M Oral Care, St. Paul, MN, USA) inserted incrementally and Bulk-OPUS, (Opus Bulk Fill APS, FGM, Joinville, SC, Brazil) high viscosity bulk fill resin composite (n=10). As a control, a typodont having intact teeth without restorations was used. After the restorative procedure, each specimen was radiographed using a digital system (Dürr Dental, Bietigheim-Bissingen, Germany). The proximal contact force (N) was measured using dental floss with a microtensile machine (Microtensile ODEME, Luzerna, SC, Brazil). The specimens were then subjected to mechanical fatigue cycling to simulate 5 years of aging. All the parameters were measured after aging. The X-rays were blindly qualitatively analyzed by two operators to identify the loss of proximal contact. One-way ANOVA was used for comparing the initial contact force between restored and intact teeth. Two-way ANOVA followed by Tukey testing was performed for contact area data and for the contact force/contact area ratio. The proximal contact force data were analyzed using one-way repeated measurement ANOVA followed by Tukey testing (α=0.05). The X-ray proximal contact analyses were described by the frequency. RESULTS The initial proximal contact force was similar for intact and restored teeth. The contact force and contact area with the molar were significantly higher than with the premolar; however the contact force/contact area ratio was similar for all tested groups. The bulk fill technique showed a contact force similar to the incremental filling technique. Fatigue resulted in a significant reduction in the proximal contact force (p<0.001), irrespective of the region analyzed or restorative material used. The digital X-rays detected no alteration in the proximal contact after occlusal fatigue. CONCLUSIONS Larger contact area resulted in higher proximal contact force. Proximal contact force decreased with 5 years of simulated occlusal fatigue. The bulk fill technique showed a proximal contact force similar to that of the incremental filling technique.
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Affiliation(s)
- Lrs Oliveira
- Lais Rani Sales Oliveira, DDS, MSc, PhD student, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlandia, MG, Brazil
| | - C Melo
- Calebe de Melo, DDS, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, MG, Brazil
| | - Kgba Cavalcanti
- Karoline Guará Brusaca Almeida Cavalcanti, DDS, MSc, PhD student, School of Dentistry, CEUMA University, São Luis, MA, Brazil
| | - Pbf Soares
- Priscilla Barbosa Ferreira Soares, DDS, MSc, PhD, professor, Department of Periodontology and Implantology, School of Dentistry, Universidade de Uberlândia, Uberlândia, MG, Brazil
| | - Afm Cardenas
- Andres Felipe Millan Cardenas, DDS, MSc, PhD, professor, Postgraduate Program in Dentistry, CEUMA University, São Luis, MA, Brazil
| | - C J Soares
- *Carlos José Soares, DDS, MSc, PhD, professor, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlandia, Minas Gerais, Brazil
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Tosco V, Monterubbianesi R, Furlani M, Giuliani A, Putignano A, Orsini G. Micro-computed tomography for assessing the internal and external voids of bulk-fill composite restorations: A technical report. Imaging Sci Dent 2022; 52:303-308. [PMID: 36238708 PMCID: PMC9530296 DOI: 10.5624/isd.20220007] [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: 01/11/2022] [Revised: 04/13/2022] [Accepted: 04/27/2022] [Indexed: 11/18/2022] Open
Abstract
Purpose Materials and Methods Results Conclusion
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Affiliation(s)
- Vincenzo Tosco
- Department of Clinical Sciences and Stomatology, Polytechnic University of Marche, Ancona, Italy
| | - Riccardo Monterubbianesi
- Department of Clinical Sciences and Stomatology, Polytechnic University of Marche, Ancona, Italy
| | - Michele Furlani
- Department of Clinical Sciences and Stomatology, Polytechnic University of Marche, Ancona, Italy
| | - Alessandra Giuliani
- Department of Clinical Sciences and Stomatology, Polytechnic University of Marche, Ancona, Italy
| | - Angelo Putignano
- Department of Clinical Sciences and Stomatology, Polytechnic University of Marche, Ancona, Italy
| | - Giovanna Orsini
- Department of Clinical Sciences and Stomatology, Polytechnic University of Marche, Ancona, Italy
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10
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Cardoso IO, Machado AC, Fernandes LDO, Soares PV, Raposo LHA. Influence of Tip Diameter and Light Spectrum of Curing Units on the Properties of Bulk-Fill Resin Composites. Eur J Dent 2021; 16:360-366. [PMID: 34905778 PMCID: PMC9339921 DOI: 10.1055/s-0041-1735799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Objective
The aim of this study was to evaluate the influence of different light-curing units (LCUs) with distinct tip diameters and light spectra for activating bulk-fill resins.
Materials and Methods
The specimens (
n
= 10) were made from a conventional composite (Amaris, VOCO) and bulk-fill resins (Aura Bulk Fill, SDI; Filtek One, 3M ESPE; Tetric Bulk Fill, Ivoclar Vivadent) with two diameters, 7 or 10 mm, × 2 mm thickness. Following 24 hours of specimen preparation, the degree of conversion (DC) was evaluated using the Fourier-transform infrared unit. Knoop hardness (KHN) readings were performed on the center and periphery of the specimens. Data were assessed for homoscedasticity and submitted to one-way and three-way analysis of variance followed by the Tukey's and Dunnett's tests, depending on the analysis performed (α = 0.05).
Results
LCUs and specimen diameter significantly affected the DC. The
Tetric Bulk Fill
provided increased DC results when light-cured with
Valo
(54.8 and 53.5%, for 7 and 10 mm, respectively) compared with
Radii Xpert
(52.1 and 52.9%, for 7 and 10 mm, respectively). No significant differences in KHN results were noted for the conventional resin composite (
Amaris
) compared with LCUs (
p
= 0.213) or disc diameters (
p
= 0.587), but the center of the specimen exhibited superior KHN (
p
≤ 0.001) than the periphery.
Conclusion
The light spectrum of the multipeak LCU (
Valo
) significantly increased the DC and KHN of the bulk-fill resin composite with additional initiator to camphorquinone (
Tetric Bulk Fill
) compared with the monowave LCU (
Radii Xpert
). The tip size of the LCUs influenced the performance of some of the resin composites tested.
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Affiliation(s)
- Igor Oliveiros Cardoso
- Department of Occlusion, Fixed Prosthodontics and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Brazil
| | | | - Luísa de Oliveira Fernandes
- Department of Occlusion, Fixed Prosthodontics and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Brazil
| | - Paulo Vinícius Soares
- Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Brazil
| | - Luís Henrique Araújo Raposo
- Department of Occlusion, Fixed Prosthodontics and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Brazil
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Rodrigues MDP, Cunha LSD, Vilela ABF, Schettini ACT, Bragança GFD, França R, Soares CJ. Selective carious tissue removal and glass ionomer liner reduction of pulp stress in bulk fill resin composite restorations. Braz Oral Res 2021; 35:e119. [PMID: 34878074 DOI: 10.1590/1807-3107bor-2021.vol35.0119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/10/2021] [Indexed: 11/21/2022] Open
Abstract
To evaluate the effect of selective or nonselective carious tissue removal and the use of a resin-modified glass ionomer (RMGIC) liner under bulk fill resin composite restoration on the stress at the pulp chamber, the elastic moduli of hard, firm, soft and intact dentin were calculated using nanoindentation. Post-gel shrinkage of the bulk fill resin composite and RMGIC were determined using the strain-gauge method. Six finite element models were created by using digital radiography with the combination of two study factors: a) carious tissue removal: selective removal or nonselective removal of carious tissue, and b) use of RMGIC liner: with or without 1.0 mm of RMGIC liner. The modified von Mises stresses (mvm) (MPa) were extracted on the nodes of the internal wall of the pulp ceiling chamber at 100 N occlusal loading. Data were analyzed descriptively and recorded quantitively. Both study factors influenced the stress distribution. The mvm stress during the restorative procedure was higher for nonselective carious tissue removal without RMGIC (25.9 MPa) and lower for selective carious tissue removal associated with RMGIC (13.5 MPa). The dentin elastic modulus increased from soft carious (3.6 ± 0.3 MPa) to firm carious (5.2 ± 1.0 MPa) to hard carious (10.9 ± 1.2 MPa) to intact dentin (22.7 ± 3.0 MPa). Molars with carious lesions showed high mvm stress at the pulp ceiling (89.6 MPa) and at fragilized coronal structure remaining. Selective carious tissue removal followed by restoration using a Vitrebond liner and Tetric N-Ceram Bulk fill reduced the stress at the pulp chamber ceiling.
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Affiliation(s)
- Monise de Paula Rodrigues
- Universidade Federal de Uberlândia - UFU, School of Dentistry, Department of Operative Dentistry and Dental Materials, Uberlândia, MG, Brazil
| | - Laryssa Silva da Cunha
- Universidade Federal de Uberlândia - UFU, School of Dentistry, Department of Operative Dentistry and Dental Materials, Uberlândia, MG, Brazil
| | - Andomar Bruno Fernandes Vilela
- Universidade Federal de Uberlândia - UFU, School of Dentistry, Department of Operative Dentistry and Dental Materials, Uberlândia, MG, Brazil
| | - Ana Cecília Teodoro Schettini
- Universidade Federal de Uberlândia - UFU, School of Dentistry, Department of Operative Dentistry and Dental Materials, Uberlândia, MG, Brazil
| | - Gabriel Felipe de Bragança
- Universidade Federal de Uberlândia - UFU, School of Dentistry, Department of Operative Dentistry and Dental Materials, Uberlândia, MG, Brazil
| | - Rodrigo França
- University of Manitoba, Faculty of Health Science, College of Dentistry, Department of Restorative Dentistry, Winnipeg, Canada
| | - Carlos José Soares
- Universidade Federal de Uberlândia - UFU, School of Dentistry, Department of Operative Dentistry and Dental Materials, Uberlândia, MG, Brazil
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Polymerization shrinkage and shrinkage stress of bulk-fill and non-bulk-fill resin-based composites. J Dent Sci 2021; 17:1212-1216. [PMID: 35784133 PMCID: PMC9237169 DOI: 10.1016/j.jds.2021.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 12/03/2021] [Indexed: 11/22/2022] Open
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Ardestani SS, Bonan RF, Mota MF, Farias RMDC, Menezes RR, Bonan PRF, Maciel PP, Ramos-Perez FMDM, Batista AUD, da Cruz Perez DE. Effect of the incorporation of silica blow spun nanofibers containing silver nanoparticles (SiO 2/Ag) on the mechanical, physicochemical, and biological properties of a low-viscosity bulk-fill composite resin. Dent Mater 2021; 37:1615-1629. [PMID: 34479726 DOI: 10.1016/j.dental.2021.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 08/14/2021] [Accepted: 08/17/2021] [Indexed: 11/16/2022]
Abstract
OBJECTIVE This work aimed at producing silica-blow-spun nanofibers containing silver nanoparticles (SiO2/Ag) and investigating the effect of their incorporation in different proportions, with or without pre-treatment with a silane coupling agent, on the mechanical, physicochemical, and biological properties of a commercial composite low-viscosity bulk-fill resin. METHODS The production of SiO2/Ag nanofibers was confirmed by transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX). A portion of the produced nanofibers was silanized. Scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), contact angle measurements, and agar diffusion tests against Streptococcus mutans were used to verify the differences between silanized and non-silanized nanofibers. Different proportions (0.5 wt% and 1 wt%) of silanized (SiO2/Ag-0.5S and SiO2/Ag-1S) and non-silanized (SiO2/Ag-0.5NS and SiO2/Ag-1NS) nanofibers were incorporated into the bulk-fill composite (Opus Bulk Fill Flow, FGM). A commercial composite was used as the control. Evaluation of the color parameters (L*, a*, and b*), radiopacity, contact angle, antimicrobial activity, Vickers microhardness, surface roughness (Sa and Sq), flexural strength, and SEM of the fractured surfaces were performed. The data were analyzed using the Mann-Whitney U test (fiber morphology), Kruskal-Wallis tests, with Dunn's post hoc test (antimicrobial activity of the specimen against S. mutans), Student's t-test (disk diffusion), one-way ANOVA and Tukey (color, radiopacity, and contact angle), and two-way ANOVA and Tukey (microhardness, surface roughness, and flexural strength) tests. All statistical analyses were performed at a significance level of 1% (α = 0.01). RESULTS Porous nanometric SiO2/Ag fibers were successfully produced. The silanization process, confirmed by FTIR, increased the diameter and contact angle and reduced the growth inhibition halos of the nanofibers (p < 0.01). After the incorporation of nanofibers into the dental composite, all color parameters were altered in all the experimental groups (p < 0.01). All the groups presented adequate radiopacity values. No statistical difference was observed in the contact angles of the experimental composites (p > 0.01). The lowest microbial counts were obtained in the SiO2/Ag-0.5S group; although no significant difference was observed with the control group (p < 0.01). The SiO2/Ag-1S, SiO2/Ag-0.5S, and SiO2/Ag-0.5NS groups exhibited higher microhardness after 30 d of immersion in water (p < 0.01). The surface roughness (Sa-μm) resembled that of the control at baseline, except for the SiO2/Ag-1NS group. For the baseline evaluation of flexural strength, all the experimental groups exhibited lower values than the control, except for SiO2/Ag-0.5NS and SiO2/Ag-0.5S, but after 30 d of immersion in water, there was no difference (p < 0.01). SIGNIFICANCE The incorporation of 0.5% wt. of silanized nanofibers in the commercial composite (SiO2/Ag-0.5S) seemed to be promising, especially for its greater inhibition of S. mutans, adequate roughness, and flexural strength, in addition to high hardness, even after aging in water.
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Affiliation(s)
| | - Roberta Ferreti Bonan
- Universidade Federal de Pernambuco, School of Dentistry, Recife, Pernambuco, Brazil; Federal University of Paraiba, Department of Dentistry, João Pessoa, Paraiba, Brazil.
| | - Mariaugusta Ferreira Mota
- Federal University of Campina Grande, Department of Materials Engineering, Campina Grande, Paraiba, Brazil.
| | | | - Romualdo Rodrigues Menezes
- Federal University of Campina Grande, Department of Materials Engineering, Campina Grande, Paraiba, Brazil.
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The Effect of Er:YAG Laser on a Shear Bond Strength Value of Orthodontic Brackets to Enamel-A Preliminary Study. MATERIALS 2021; 14:ma14092093. [PMID: 33919108 PMCID: PMC8122582 DOI: 10.3390/ma14092093] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/13/2021] [Accepted: 04/19/2021] [Indexed: 12/31/2022]
Abstract
We sought to evaluate the effects of Er:YAG laser (LightTouch, LightInstruments, Israel) conditioning on enamel roughness and shear bond strength of orthodontic brackets on enamel. Eighteen human molars (n = 9) and premolars (n = 9), were divided into 3 groups depending on the enamel conditioning method; Er:YAG laser (G1, n = 6), conventional etching with 37% orthophosphoric acid (G2, n = 6), Er:YAG laser combined with conventional etching (G3, n = 6). Er:YAG laser parameters were as follows: energy: 100 mJ, frequency: 10 Hz, exposure time: 10 s, applicator diameter: 600 μm, fluence: 35.37 J/cm2, distance: 1 mm away from a tooth, cooling: 80%. An MTS 858 MiniBionix® machine was used to determine the shear bond strength (MTS System, Eden Prairie, MN, USA). The enamel structure was assessed using X-ray microtomography (SkyScan 1172, Bruker, Kontich, Belgium). The highest values of shear bond strength were obtained in the G3 group (9.23 ± 2.38 MPa) and the lowest values in the G2 group (6.44 ± 2.11 MPa) (p < 0.05). A significant change in the enamel surface was noted after applying laser, reaching up to 9% of enamel thickness, which was not observed in the etched samples. Moreover, the Er:YAG laser-irradiated enamel surface was characterized by the greatest roughness. The combined use of an Er:YAG laser with a conventional etching improves the adhesion of composite materials to the tooth.
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Lin J, Lin Z, Zheng Z. Effect of different restorative crown design and materials on stress distribution in endodontically treated molars: a finite element analysis study. BMC Oral Health 2020; 20:226. [PMID: 32811484 PMCID: PMC7437004 DOI: 10.1186/s12903-020-01214-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 08/10/2020] [Indexed: 11/23/2022] Open
Abstract
Background The purposes of this simulation study were to evaluate the stresses in the roots of endodontically treated molars with extensive coronal tissue loss which were restored by endocrowns (all-in-one core and crown) and traditional crowns with post-cores, during masticatory simulation using finite element analysis. Methods A mesio-distal cross-section of a lower right first molar was digitized and used to create 2-dimensional models of the teeth and supporting tissue; different crown designs, viz., endocrown with 2 mm occlusal clearance, endocrown with 4 mm occlusal clearance and post-core crown; different crown materials, viz., zirconia (Zr) and lithia-disilicate reinforced glass ceramic (LDRGC), and different post and core materials, viz., glass fiber (GF), stainless steel (SS) and metal cast (MC). An axial load of 600 N was applied to the central fossa of occlusal surface. Results The stress distributions were similar between Zr and LDRGC for periodontal ligament and alveolar bone. The root canal inner wall maximum principal stresses of SS post (70.8 MPa) and MC post (71.4 MPa) were higher than that of GF post (36.0 MPa) and endocrown (2.4 MPa). Conclusion The endocrowns reduced stress concentration for the root canal inner wall in comparison with the conventional post-core crown. Molars restored with endocrowns are less prone to root fracture than those with posts.
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Affiliation(s)
- Jie Lin
- Fujian Key Laboratory of Oral Diseases, School and Hospital of Stomatology, Fujian Medical University, 246 Yangqiao Zhong Road, Fuzhou, Fujian, 350002, People's Republic of China.,Department of Crown and Bridge, School of Life Dentistry at Tokyo, The Nippon Dental University, 1-9-20 Fujimi, Chiyoda-ku, Tokyo, 102-8159, Japan
| | - Zhenxiang Lin
- Department of Stomatology, Hospital of Fujian Provincial Authorities, 68 Guping Road, Fuzhou, Fujian, 350001, People's Republic of China
| | - Zhiqiang Zheng
- Fujian Key Laboratory of Oral Diseases, School and Hospital of Stomatology, Fujian Medical University, 246 Yangqiao Zhong Road, Fuzhou, Fujian, 350002, People's Republic of China.
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Roulet JF, Gummadi S, Hussein HS, Abdulhameed N, Shen C. In vitro wear of dual-cured bulkfill composites and flowable bulkfill composites. J ESTHET RESTOR DENT 2020; 32:512-520. [PMID: 32602646 DOI: 10.1111/jerd.12616] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The objective of this study is to test the wear of dual-cured bulkfill and flowable bulkfill composites. MATERIALS AND METHODS Six dual-cured bulkfill composites, Cention, Cention-Exp, Activa, Fill-up, Hyperfil Injectafill, and two flowable bulkfill composites Tetric Evoflow BulkFill and G-aenial Universal Flo were tested in this study (n = 8). Each composite was applied into an aluminum sample holder and cured with a Valo Grand (1230 mW/cm2 ) or self-cured according to manufacturer's recommendations, and stored in water for 3 weeks. The samples were subjected to 120 000 load cycles of 49 N (CS-4) against spherical steatite antagonists and simultaneously subjected to 4440 thermocycles (5°C-55°C). At intervals between load cycles, polyvinyl siloxane impressions were taken and scanned with a True Definition Laser Scanner. The volumetric wear was calculated using image software (Geomagic). Microscopic images of selected wear facets and their corresponding worn antagonists were obtained using SEM. All data were analyzed using analysis of variance (ANOVA) and Tukey post hoc test for multiple comparison (α = .05; β = .2). RESULTS The load cycles volumetric wear-increase was linear. Two-way ANOVA showed significant main effects (material and light-cured) and significant interactions. Self-cured materials (mean = 0.38 mm3 ) showed more wear than light-cured materials (mean = 0.35mm3 ). CONCLUSIONS The bioactive materials except Activa light-cured showed significantly more wear than the flowable composites. CLINICAL SIGNIFICANCE This study demonstrated that most of the dual-cured composites, if light-cured, showed the same wear as the flowable composites used as control. Therefore, to obtain adequate wear resistance the dual-cured composites should be routinely light-cured.
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Affiliation(s)
- Jean-François Roulet
- Department of Restorative Dental Science, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Snigdha Gummadi
- Department of Restorative Dental Science, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Hind S Hussein
- LECOM School of Dental Medicine, Bradenton, Florida, USA
| | | | - Chiayi Shen
- Department of Restorative Dental Science, College of Dentistry, University of Florida, Gainesville, Florida, USA
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da Silva Pereira RA, de Bragança GF, Vilela ABF, de Deus RA, Miranda RR, Veríssimo C, Soares CJ. Post-gel and Total Shrinkage Stress of Conventional and Bulk-fill Resin Composites in Endodontically-treated Molars. Oper Dent 2020; 45:E217-E226. [DOI: 10.2341/19-187-l] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2020] [Indexed: 11/23/2022]
Abstract
Clinical Relevance
The clinician should consider the polymerization shrinkage stress when selecting a composite resin for posterior restorations. The use of post-gel shrinkage values should guide the selection of a composite resin for posterior teeth.
SUMMARY
Objectives: The objective of this study was to evaluate the effect of the method used for calculation of polymerization shrinkage, total or post-gel, on the shrinkage stress of conventional and bulk-fill composite resins for restoring endodontically treated teeth using finite element analysis.
Methods and Materials: Four composite resins were tested for post-gel shrinkage (P-Shr) by the strain-gauge test and total shrinkage (TShr) using an optical method (n=10). Two conventional composite resins, Filtek Z350 XT (3M-ESPE; Z350) and TPH3 Spectrum (Dents-ply; TPH3) and two bulk-fill composite resins. Filtek Bulk-Fill Posterior (3M-ESPE; POST) SureFil SDR flow (Dentsply; SDR) were tested. Elastic modulus (E), diametral tensile strength (DTS), and compressive strength (CS) were also determined (n=10). The residual shrinkage stress was evaluated by finite element analysis with four restorative techniques: incremental with Z350 and TPH3; SDR/TPH3 (two bulk increments of 4 mm and two occlusal increments); and two bulk increments of 5 mm for POST. Data for P-Shr, T-Shr, E, DTS, and CS were analyzed by analysis of variance and Tukey’s test (α=0.05), and residual shrinkage was analyzed quantitatively and qualitatively by the modified von Mises criteria.
Results: SDR had the lowest CS values, POST and TPH3 had similar and intermediate values, and Z350 had the highest CS. TPH3 and Z350 had similar DTS values and values higher than SDR. Z350 and POST had higher P-Shr, and SDR had lower T-Shr. T-Shr resulted in higher shrinkage stress than P-Shr values. SDR/TPH3 resulted in higher shrinkage stress when using T-Shr and lower values when using the P-Shr value.
Conclusion: T-Shr resulted in higher stress in the enamel and in root dentin close to the pulp chamber than P-Shr values. The selection of the T-Shr or P-Shr changed the ranking of the shrinkage stress of the tested composite resin.
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Clinical performance and chemical-physical properties of bulk fill composites resin -a systematic review and meta-analysis. Dent Mater 2019; 35:e249-e264. [PMID: 31421957 DOI: 10.1016/j.dental.2019.07.007] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 07/08/2019] [Accepted: 07/15/2019] [Indexed: 11/20/2022]
Abstract
OBJECTIVES The objective of this study was to perform a meta-analysis of clinical and laboratory studies to compare the performance of bulk-fill and conventional composite resins in terms of polymerization shrinkage, polymerization stress, cusp deflection, marginal quality, degree of conversion, microhardness, flexural strength, fracture strength and clinical performance. DATA One hundred three articles were included in this study, and the Peto method was used to compare the bulk-fill and conventional composites using the RevMan software. SOURCES Searches were performed in the PubMed and Scopus databases. STUDY SELECTION Laboratory studies and randomized clinical trials comparing one of the previous detailed outcomes between bulk-fill and control composites were included. CONCLUSIONS The bulk-fill composite resins showed less shrinkage, polymerization stress, cusp deflection and microhardness than conventional composites, while both materials presented a similar marginal quality, flexural strength and fracture strength. Also, bulk-fill materials with regular viscosity showed similar shrinkage. The conversion of bulk-fill materials with flowable consistency were similar to conventional composite resins with a thickness of up to 2mm and greater than conventional composites with a thickness greater than 2mm. Despite these in vitro differences, the clinical performance of bulk-fill and conventional composite resins was similar in randomized clinical trials, with one to ten years of follow up. In conclusion, the bulk-fill materials show better or similar performance to the conventional materials in clinical trials and laboratory studies in terms of volumetric shrinkage, polymerization stress, cusps deflection and marginal quality, with the only exception being the lower level of microhardness observed for bulk-fill composites with thickness up to 2mm.
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