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Bai X, Chen Y, Zhou T, Pow EHN, Tsoi JKH. The chemical and optical stability evaluation of injectable restorative materials under wet challenge. J Dent 2024; 146:105031. [PMID: 38710315 DOI: 10.1016/j.jdent.2024.105031] [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: 03/07/2024] [Revised: 04/08/2024] [Accepted: 04/27/2024] [Indexed: 05/08/2024] Open
Abstract
OBJECTIVES To investigate and compare the chemical and optical stability of four restorative composite materials: two injectable resins, one flowable resin and one compomer. METHODS Two injectable nano-filled composite resins: G-aenial Universal (GU) and Beautifil Injectable XSL (BI), a flowable composite resin: Filtek Supreme Flowable (FS) and a compomer: Dyract Flow (DF), in A2 shade were tested and compared. Water sorption and solubility were conducted according to ISO4049:2019 standard; ICP-OES and F-ion selective electrode were used to test the elemental release; Degree of conversion (DC) was obtained by using FTIR; water contact angle was obtained by static sessile drop method, and a spectrophotometer was used for optical properties (ΔE⁎, ΔL⁎ and TP). SPSS 28.0 was used for statistical analysis and the significant level was pre-set as α = 0.05. RESULTS GU performed the best in water sorption and solubility, FS had the lowest elemental release, the best colour stability, and the highest DCIM and DC24-h. DF, the compomer had the lowest, and GU and BI, the injectable composites had the largest water contact angle, respectively. Correlations were found between water sorption and water solubility. CONCLUSIONS The four composite restorative materials showed different chemical and optical behaviours. Overall, composite resins performed better than compomer, while additional laboratory and in vivo tests are necessary to obtain a more comprehensive comparison between injectable and flowable composite resins. Wsp and Wsl are influenced by many common factors, and the values are highly positively related. CLINICAL SIGNIFICANCE A comprehensive understanding of materials is crucial before selecting materials for clinical practice. Composite resins rather than compomers are recommended because of their exceptional properties, which make them eligible for a wide range of clinical applications and an elongated lifespan.
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Affiliation(s)
- Xuedong Bai
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Yanning Chen
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Tianyu Zhou
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Edmond Ho Nang Pow
- Prosthodontics, Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - James Kit Hon Tsoi
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China.
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Chen Y, Bai X, Xu M, Zhou T, Loh YM, Wang C, Pow EHN, Tsoi JKH. The mechanical, wear, antibacterial properties and biocompatibility of injectable restorative materials under wet challenge. J Dent 2024; 146:105025. [PMID: 38697507 DOI: 10.1016/j.jdent.2024.105025] [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: 03/07/2024] [Revised: 04/08/2024] [Accepted: 04/24/2024] [Indexed: 05/05/2024] Open
Abstract
OBJECTIVES To evaluate the mechanical, wear, antibacterial properties, and biocompatibility of injectable composite materials. METHODS Two injectable composite resins (GU and BI), one flowable composite resin (FS), and one flowable compomer (DF), in A2 shade, were tested. Mechanical properties were tested via three-point bending test immediately after preparation and after 1-day, 7-day, 14-day, and 30-day water storage. Under water-PMMA slurry immersion, specimens were subjected to a 3-body wear test (10,000 cycles) against stainless steel balls, while the roughness, wear depth, and volume loss were recorded. After 1-day and 3-day MC3T3-E1 cell culture, cell viability was evaluated with CCK-8 test kits, while the cell morphology was observed under CLSM and SEM. Antibacterial properties on S. mutans were assessed via CFU counting, CLSM, and SEM observation. SPSS 26.0 was used for statistical analysis (α = 0.05). RESULTS The mechanical properties were material-dependent and sensitive to water storage. Flexural strength ranked GU > FS > BI > DF at all testing levels. Three nanocomposites had better wear properties than DF. No significant difference on 1-day cell viability was found, but DF showed significantly lower cell proliferation than nanocomposites on 3-day assessment. GU and FS had more favourable cell adhesion and morphology. CFU counting revealed no significant difference, while FS presented a slightly thicker biofilm and BI showed relatively lower bacteria density. CONCLUSIONS Injectable nanocomposites outperformed the compomer regarding mechanical properties, wear resistance, and biocompatibility. The tested materials presented comparable antibacterial behaviours. Flowable resin-based composites' performances are affected by multiple factors, and their compositions can be attributed. CLINICAL SIGNIFICANCE A profound understanding of the mechanical, wear, and biological properties of the restorative material is imperative for the clinical success of dental restorations. The current study demonstrated superior properties of highly filled injectable composite resins, which imply their wider indications and better long-term clinical performances.
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Affiliation(s)
- Yanning Chen
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Xuedong Bai
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Mengxiao Xu
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Tianyu Zhou
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - Yee Man Loh
- State Key Laboratory of Ultra-precision Machining Technology, Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hong Kong, PR China
| | - Chunjin Wang
- State Key Laboratory of Ultra-precision Machining Technology, Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hong Kong, PR China
| | - Edmond Ho Nang Pow
- Prosthodontics, Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China
| | - James Kit Hon Tsoi
- Dental Materials Science, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China.
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Sakuma K, Horie T, Kishimoto T, Maesako M, Tomoda S, Fujitani M, Tsujimoto A. Investigation on the Biaxial Flexural Strength of Universal Shade Resin-Based Composites. Polymers (Basel) 2024; 16:1853. [PMID: 39000708 PMCID: PMC11244099 DOI: 10.3390/polym16131853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 07/17/2024] Open
Abstract
The biaxial flexural strength of universal shade and conventional dental resin-based composites before and after alkaline degradation was investigated. Disk samples were prepared from these resin-based composites, and some of the specimens were immersed in 0.1 M NaOH solution to create deteriorated samples. The biaxial flexural strength of the samples before and after the alkaline degradation test was measured and statistically tested. The fracture surfaces after the biaxial flexural test were observed using a scanning electron microscope. The results showed that the biaxial flexural strength of the paste-type universal shade resin-based composite before alkaline degradation was significantly (19%) higher than that of the conventional type, but no difference was observed between the materials after alkaline degradation. On the other hand, the biaxial flexural strength of the flowable universal shade resin-based composites was significantly (around 35%) lower than that of the conventional composite, with or without degradation. Although, for paste-type materials, the biaxial flexural strength of universal shade resin-based composites was higher than that of conventional resin-based composites before alkaline degradation, after degradation the two materials showed similar values. For flowable materials, the biaxial flexural strength of universal shade resin-based composites was lower than that of conventional resin-based composites regardless of the presence or absence of degradation processes. These results suggest that some caution should be used when deciding whether to use flowable universal shade resin-based composite to fill a cavity.
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Affiliation(s)
- Keiko Sakuma
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
| | - Taku Horie
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
- BIOMAT—Biomaterials Research Group & UZ Leuven (University Hospitals Leuven), Dentistry, KU Leuven (University of Leuven) Department of Oral Health Sciences, 3000 Leuven, Belgium
| | - Takafumi Kishimoto
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
| | - Mayumi Maesako
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
| | - Shigetaka Tomoda
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
| | - Morioki Fujitani
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
| | - Akimasa Tsujimoto
- Department of Operative Dentistry, School of Dentistry, Aichi Gakuin University, Nagoya 464-8651, Japan; (K.S.); (T.K.); (M.M.); (S.T.); (M.F.); (A.T.)
- Department of Operative Dentistry, University of Iowa College of Dentistry, Iowa City, IA 52242, USA
- Department of General Dentistry, Creighton University School of Dentistry, Omaha, NE 68102, USA
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Basheer RR, Hasanain FA, Abuelenain DA. Evaluating flexure properties, hardness, roughness and microleakage of high-strength injectable dental composite: an in vitro study. BMC Oral Health 2024; 24:546. [PMID: 38730400 PMCID: PMC11088093 DOI: 10.1186/s12903-024-04333-3] [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: 03/10/2024] [Accepted: 05/03/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Recently, a new generation of high-strength flowable dental composites has been introduced by manufacturers. The manufacturers claim that these materials have enhanced mechanical and physical properties and are suitable for use in a wide range of direct anterior and posterior restorations, even in high-stress bearing areas. AIM The objective of this study was to assess certain physical and mechanical properties of these recently introduced high-strength flowable composites in comparison to conventional multipurpose dental composites. METHODS Four types of high-strength flowable composites (Genial Universal FLO, Gaenial Universal Injectable, Beautifil Injectable, and Beautifil Flow Plus) were tested in experimental groups, while a nanohybrid conventional composite (Filtek Z350 XT) was used as the control. For flexure properties, ten rectangular samples (2 × 2 × 25 mm) were prepared from each composite material and subjected to 5000 cycles of thermocycling. Samples were then subjected to flexural strength testing using the universal testing machine. Another twenty disc-shaped specimens of dimensions (5 mm diameter × 2 mm thickness) were fabricated from each composite material for surface roughness (Ra) (n = 10) and hardness (VHN) test (n = 10). All samples underwent 5000 cycles of thermocycling before testing. Additionally, microleakage testing was conducted on 60 standardized class V cavities prepared on molar teeth and divided randomly into five groups (n = 12). Cavities were then filled with composite according to the manufacturer's instructions and subjected to thermocycling for 1000 cycles before testing using methylene blue solution and a stereomicroscope. RESULTS All tested materials were comparable to the control group in terms of flexural strength and surface roughness (p > 0.05), with Gaenial Universal FLO exhibiting significantly higher flexural strength compared to the other flowable composite materials tested. However, all tested materials demonstrated significantly lower elastic modulus and surface hardness than the control group (p < 0.05). The control group exhibited higher microleakage scores, while the lowest scores were observed in the Gaenial Universal FLO material (p < 0.05) CONCLUSION: The physical and mechanical behaviors of the different high-strength flowable composites investigated in this study varied. Some of these materials may serve as suitable alternatives to conventional composites in specific applications, emphasizing the importance of dentists being familiar with material properties before making material selections.
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Affiliation(s)
- Rasha R Basheer
- Restorative Dentistry Department, Operative dentistry division, King Abdulaziz University, Jeddah, Saudi Arabia.
- Conservative Dentistry Department, Faculty of Dentistry, October University for Modern Sciences and Arts, Giza, Egypt.
| | - Fatin A Hasanain
- Restorative Dentistry Department, Operative dentistry division, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Dalia A Abuelenain
- Restorative Dentistry Department, Operative dentistry division, King Abdulaziz University, Jeddah, Saudi Arabia
- Restorative Dentistry Department, Biomaterials Division, King Abdulaziz University, Jeddah, Saudi Arabia
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Parra Gatica E, Duran Ojeda G, Wendler M. Contemporary flowable bulk-fill resin-based composites: a systematic review. Biomater Investig Dent 2023; 10:8-19. [PMID: 37138762 PMCID: PMC10150621 DOI: 10.1080/26415275.2023.2175685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Flowable bulk-fill resin-based composites (BF-RBCs) represent a new and interesting alternative for the bulk-fill restorative techniques in the posterior region. However, they comprise a heterogeneous group of materials, with important differences in composition and design. Therefore, the aim of the present systematic review was to compare the main properties of flowable BF-RBCs, including their composition, degree of monomer conversion (DC), polymerization shrinkage and shrinkage stress, as well as flexural strength. The search was conducted following PRISMA guidelines in the Medline (PubMed), Scopus and Web of Science databases. In vitro articles reporting on the DC, polymerization shrinkage/shrinkage stress, and flexural strength of flowable BF-RBCs strength were included. The QUIN risk-of-bias (RoB) tool was used for assessing the study quality. From initially 684 found articles, 53 were included. Values for DC ranged between 19.41 and 93.71%, whereas polymerization shrinkage varied between 1.26 and 10.45%. Polymerization shrinkage stresses reported by most studies ranged between 2 and 3 MPa. Flexural strength was above 80 MPa for most materials. A moderate RoB was observed in most studies. Flowable BF-RBCs meet the requirements to be indicated for bulk fill restoration technique in the posterior region. However, important variations among composition and properties hinder extrapolation of the results to materials different from those reported here. Clinical studies are urgently required to assess their performance under a real working scenario.
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Affiliation(s)
- Elizabeth Parra Gatica
- Master Program in Dental Sciences, Faculty of Dentistry, Universidad de Concepción, Concepción, Chile
| | | | - Michael Wendler
- Master Program in Dental Sciences, Faculty of Dentistry, Universidad de Concepción, Concepción, Chile
- Department of Restorative Dentistry, Faculty of Dentistry, Universidad de Concepción, Concepción, Chile
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Souza LVS, Pavanello L, Picolo MZD, Kury M, Matos ICRT, Cogo-Müller K, Esteban Florez FL, Cavalli V. Mechanical and antibacterial properties of an experimental flowable composite containing Nb 2O 5 and NF_TiO 2 nanoparticles. J Mech Behav Biomed Mater 2023; 143:105919. [PMID: 37279637 DOI: 10.1016/j.jmbbm.2023.105919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 06/08/2023]
Abstract
This study developed an experimental flowable composite incorporated with niobium pentoxide (Nb2O5) combined or not with titanium dioxide co-doped with fluorine and nitrogen (NF_TiO2) and evaluated the mechanical and antibacterial properties. The experimental flowable composite (TEGDMA + BisGMA 1:1 + 60%wt - inorganic filler - borosilicate 0.7 μm) was formulated according to the type and concentration of Nb2O5 and NF_TiO2 (0.5, 1, 1.5 and 2 wt%) or NF_TiO2 + Nb2O5 (0.25, 0.5, 0.75 and 1 wt% - 1:1). The control groups were formed by the experimental composite without the incorporation of Nb2O5 and/or NF_TiO2 (GC-E) and by a commercial flowable composite (GC). The characterization of the surface of the composite and its particles was carried out using scanning electron microscopy (SEM) and energy dispersive x-rays (EDX). Specimens were manufactured and subjected to mechanical tests of flexural strength (FS) (n = 12), flexural modulus (FM) (n = 12), roughness (Ra) (n = 10), microhardness (n = 10), and contact angle (n = 10); and, to evaluate the antibacterial activity, they were submitted to tests of biofilm formation against S. mutans (CFU/mL) (n = 5), biofilm biomass by dry weight (n = 5) and confocal laser microscopy (%LIVE/DEAD) (n = 5). Data were submitted to one-way ANOVA and Tukey's post-hoc and, those that were not homoscedastic, but with normality, were submitted to Welch's ANOVA and Games-Howell's post-hoc. Dunnet's test was used to compare the controls with the other experimental groups (α = 5). The Nb2O5 particles had an average size of 32.4 μm and the nanoparticles (NPs) of NF_TiO2, 10 nm. EDX analysis identified isolated peaks of N, F, Ti, and Nb confirming the presence of these particles in the resin matrix. The 1.5% NF_TiO2 group had a higher FS and FM than the controls (p < 0.05). GC showed higher microhardness between groups (p < 0.05). There was no difference between the experimental groups regarding contact angle and roughness (p > 0.05), except for GC, which had the highest Ra values and the lowest contact angle between groups (p < 0.05). Composites containing 0.5%, 1%, 1.5%, and 2% Nb2O5, 1%, 1.5%, and 2% NF_TiO2 and 2% Nb2O5 + NF_TiO2 showed lower biofilm formation (p < 0.05), lower total biofilm biomass (p < 0.05), and a higher percentage of dead cells (44%, 52%, 52%, 79%, 42% 43%, 62%, 65%, respectively) than GC and GC-E (5% and 1%, respectively). It is concluded that the incorporation of 1.5% NF_TiO2 promoted a greater FS and FM among the experimental composites and that the addition of Nb2O5 particles (0.5%, 1%, 1.5%, and 2%), NF_TiO2 (1%, 1.5% and 2%) and the combination Nb2O5 + NF_TiO2 (2%) showed significant antibacterial effects.
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Affiliation(s)
| | - Larissa Pavanello
- Department of Biosciences, University of Campinas, Piracicaba Dental School, Piracicaba, SP, Brazil
| | - Mayara Zaghi Dal Picolo
- Department of Restorative Dentistry, University of Campinas - Piracicaba Dental School, Piracicaba, SP, Brazil
| | - Matheus Kury
- Department of Restorative Dentistry, University of Campinas - Piracicaba Dental School, Piracicaba, SP, Brazil
| | | | - Karina Cogo-Müller
- Faculty of Pharmaceutical Sciences, University of Campinas, Campinas, SP, Brazil
| | - Fernando Luis Esteban Florez
- Division of Dental Biomaterials, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Vanessa Cavalli
- Department of Restorative Dentistry, University of Campinas - Piracicaba Dental School, Piracicaba, SP, Brazil.
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Sulca Gonzales EL, López-Flores AI. [Flexural strength of conventional flowable, bulk fill flowable and highly filled flowable resin composites: in vitro study.]. REVISTA CIENTÍFICA ODONTOLÓGICA 2023; 11:e161. [PMID: 38288001 PMCID: PMC10809959 DOI: 10.21142/2523-2754-1103-2023-161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 09/04/2023] [Indexed: 01/31/2024] Open
Abstract
Objective To evaluate and compare the flexural strength of conventional flowable, bulk fill flowable and highly filled flowable resins. Materials and methods Thirty 2mm x 2mm x 25mm specimens of Tetric N-Flow (TNF), Filtek Bulk Fill Flowable Restorative (FBF) and Beautifil Flow Plus F00 (BFP) flowable resins were made up; they were distributed into three groups according to brand (n=10) and stored in distilled water for 24 hours at 37ºC. The 3-point bending test according to ISO 4049 was performed on a universal testing machine at a speed of 0.5 mm/min until fracture. The results were evaluated with Anova and Tukey tests. P<0.05. Results Statistically significant differences were found between the groups with a value of p=0.011. According to the statistical analysis, the groups that showed statistically significant differences were the BFP and TNF groups (p=0.015) and the BFP and FBF groups (p=0.035), while no statistically significant difference was found in the TNF and FBF groups. Conclusion The high-filled flowable resin presents better flexural strength compared to the conventional flowable and bulk fill flowable resins, while the conventional and bulk fill flowable resins have no statistically significant difference.
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Affiliation(s)
- Edith Liliana Sulca Gonzales
- División de Rehabilitación Oral, Carrera de Estomatología, Universidad Científica del Sur. Lima, Perú. , Universidad Científica del Sur División de Rehabilitación Oral Carrera de Estomatología Universidad Científica del Sur Lima Peru
| | - Ana Isabel López-Flores
- División de Rehabilitación Oral, Carrera de Estomatología, Universidad Científica del Sur. Lima, Perú. , Universidad Científica del Sur División de Rehabilitación Oral Carrera de Estomatología Universidad Científica del Sur Lima Peru
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Flexural Property of a Composite Biomaterial in Three Applications. JOURNAL OF COMPOSITES SCIENCE 2021. [DOI: 10.3390/jcs5100282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Resin composite is widely used in the dental field in clinics as a biomaterial. For example, it has been used as a composite material, a type of biomaterial, to repair caries and restore masticatory function, and as a luting agent to adhere the restoration to the tooth substrate. In order to demonstrate its function, we have measured the mechanical strength. From such basic research, we explain the potential of a dental material through the measurement of flexural strength and modulus of elasticity. In this research, we introduce commercial products that are actually used as composite materials suitable for tooth substrate and provide readers with their properties based on flexural strength and modulus of elasticity. In clinical performance, it might be advisable to delay polishing when a composite material is used for a luting material, a filling material and a core build-up material, as the flexural strength and the flexural modulus of elasticity were improved after 1 day of storage, and flexural strength and characteristics are considered as important mechanical properties of oral biomaterials.
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