Probabilistic model for flexural strength of dental composites used in modeling reliability of the “tooth-dental composite” system

Ca3(PO4)2/ZrO2 dental composite ceramics using for CAD/CAM system were prepared and the effects of weak phases on microstructures and mechanical properties were studied. The results showed that intergranular spreads happened with the increasing Ca3(PO4)2 contents due to the discontinuity of weak interfaces between Zirconia and Calcium phosphate in matrix. So the flexural strength and hardness of the Ca3(PO4)2/ZrO2 composite ceramics were decreased effectively, which improved the machinability of the composites. On the other hand, strong interfaces between Zirconias increased the integrality of the ceramic structures. ZrO2 composite Ceramics with 15% Ca3(PO4)2 were sintered at 1350°C. The flexural strength is 300.44MPa, fracture toughness is 4.36 MPam1/2, and hardness is 6.69 GPa. The cutting exponent of the Ca3(PO4)2/ZrO2 composite ceramics is obviously lower than that of the common commercial Vita Mark II and Dicor MGC ceramics, which shows good mechanical properties and machinability.

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The effect of TiO2 nanotubes reinforcement on the mechanical properties and wear resistance of silica micro-filled dental composites

Journal of Composite Materials ◽

10.1177/0021998318818882 ◽

2018 ◽

Vol 53 (23) ◽

pp. 3217-3228 ◽

Cited By ~ 3

Author(s):

Abolfazl Mirjalili ◽

Ali Zamanian ◽

Seyed Mohammad Mahdi Hadavi

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Flexural Strength ◽

Water Sorption ◽

Hydrothermal Process ◽

Physical And Mechanical Properties ◽

Dental Composite ◽

Dental Composites ◽

Dental Resin ◽

Electron Microscopies

One of the most important aspects of dental resin composites is the ability to improve mechanical properties by adding reinforcing filler particles. TiO2 nanotubes are expected to improve the physical and mechanical properties of silica micro-filled dental composite. Therefore, TiO2 nanotubes were synthesized using an alkaline hydrothermal process and then functionalized with 3-methacryloxypropyl-trimethoxysilane. TiO2 nanotubes were characterized by scanning and transmission electron microscopies, X-ray diffraction and Fourier transform infrared spectroscopy. Different quantities of TiO2 nanotubes and silica microparticles were reinforced in bisphenol A-glycidyl methacrylate (Bis-GMA) and tri-ethylene glycol dimethacrylate to prepare dental composite samples. Thereafter, the flexural strength and modulus, compressive strength, degree of conversion of monomers, wear resistance and water sorption were utlized to examine the prepared composites. The flexural strength and wear resistance of composites with 3 wt% TiO2 nanotubes significantly increased in comparison with other composites. On the other hand, due to the stability of composite, the water sorption was decreased. Therefore, TiO2 nanotubes reinforcement could be a promising solution for the improvement of mechanical properties in dental composites.

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“Effect of Hydroxyapatite Nanoparticles On Compressive strength and Flexural strength of Dental Composites Using Taguchi Method”

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2022.39691 ◽

2022 ◽

Vol 10 (1) ◽

pp. 106-113

Author(s):

Shubham Padmaker Thakur

Keyword(s):

Compressive Strength ◽

Composite Materials ◽

Flexural Strength ◽

Optimization Technique ◽

Optimization Method ◽

Dental Composite ◽

Dental Composites ◽

Hydroxyapatite Nanoparticles ◽

Taguchi Optimization ◽

Long Time

Abstract: Several composite materials are being used in biomedical and dental field with their immense applications to repair and transform various organs in human body. Recent advances suggest that Hydroxyapatite is one of the most reliable and widely used inorganic composite in dentistry. Desirable applications of Hydroxyapatite are achieved by utilizing variety of hydroxyapatite and their composites. This study was conducted to evaluate the compressive & flexural strength. Cylindrical specimens (n=9) for compressive strength & rectangular shaped specimens (n=9) for flexural strength were made according to manufacturer’s recommendations. Dental composite is using quartz, silica, and alumina glass as filler for a long time. Taguchi optimization technique keeps the experimentation within limit giving valid product in the calculating of compressive and flexural strength optimization. The goal of the work is to detect the best combination of composite materials. Keywords: Hydroxyapatite, Compressive Strength, Flexural Strength, Taguchi’s optimization method.

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The Improvement of Dental Composite Properties with Electromagnetically Aligned Nanofiber

MRS Proceedings ◽

10.1557/opl.2014.728 ◽

2014 ◽

Vol 1685 ◽

Author(s):

Tansel Uyar ◽

Dilek Cokeliler

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Flexural Strength ◽

Composite Resins ◽

Dental Composite ◽

Bending Test ◽

Dental Composites ◽

Layer By Layer ◽

Aligned Fibers ◽

Electrode Systems

ABSTRACTBecause of the aesthetics, handy and low cost features, acrylic resin is the main material in denture fabrication last 40 years. The purpose of this study is to improve mechanical properties of acrylic based dental composites used in dentistry by applying nanofiber approaches. Polymethylmethacrylate (PMMA) is commonly used as a base acrylic denture material with benefits of rapid and easy handling but sometime this material can be fractured or cracked in clinical use because of the strength issues that is frequently used in restorative dentistry in recent years. A wide variety of fillers that are used to produce PMMA composites draw the attention in literature. Using PMMA composite resins with electrospun polyvinylalcohol (PVA) nanofiber fillers is our first novelty. Also the producing and using aligned electrospun fibers as a filler is our second novelty of this practice. PVA was selected as composite filler because of biocompatibility and preparing easily also has non-toxic solvent. Electrospinning system is manufactured that allows manipulation of electric field used in the application of alignment in lab scale. Various auxillary electrode systems are used for different patterns of alignment with the manufactured device and electrode systems produce fibers in different range of diameter. Scanning electron microscopy (SEM) is used for physical characterization and determined the range of fiber diameters. After the optimization of concentration step non-woven and aligned fibers are also analyzed. Non-woven fiber has no unique pattern because of the nature of electrospinning but aligned fibers has crossed lines. These produced fibers structured as layer-by-layer form with different features are used in producing PMMA dental composites with different volume ratios. In the last part of the research, PMMA dental composites are produced with aligned and formless fibers that are characterized with three-point bending test. The maximum flexural strength figure shows that fiber load by weight %0.25 and above improves the maximum. The change of flexural strength, elastic modulus values and toughness are obtained and compared with formless and aligned PVA nanofiber included composite specimens. As a result, mechanical properties of PMMA dental composites are improved with using PVA nanofibers as a filler also with the usage of aligned fibers instead of the formless ones the effects of improvement gets better with maximum values as 5.1 MPa (flexural strength), 0.8 GPa (elastic modulus), 170kJ/m3 (toughness).

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Static and dynamic mechanical behavior of microcapsule-reinforced dental composite

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420717733770 ◽

2017 ◽

Vol 233 (6) ◽

pp. 1184-1190 ◽

Cited By ~ 1

Author(s):

Akhil Sharma ◽

Sajid Alam ◽

Chetan Sharma ◽

Amar Patnaik ◽

Shiv Ranjan Kumar

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Storage Modulus ◽

Loss Modulus ◽

Triethylene Glycol ◽

Dental Composite ◽

Dental Composites ◽

Resin Matrix ◽

Cole Plot ◽

Dynamic Mechanical

Resin-based dental composites were prepared by the addition of four different weight percentages (0–9 wt% microcapsules) of silane-treated microcapsules. The resin matrix was prepared by adding 50 wt% BisGMA, 48 wt% triethylene glycol dimethylacrylate, 0.4 wt% camphorquinone, and 1.6 wt% ethyl 4 dimethyl amino benzoate, respectively. In this study, the static mechanical properties in terms of micro-hardness, compressive strength, flexural strength, and dynamic mechanical analysis, in terms of storage modulus (E′), loss modulus (E″), and Tan delta (δ) as a function of temperature were evaluated systematically as per specific standards. The mechanical results indicated that the addition of 3 wt% of microcapsules increased both the hardness and flexural strength by 38% and 6%, respectively. On the other hand, addition of 3 wt% of microcapsules on the same resin based dental composite decreased the compressive strength by 35%. The dynamic mechanical results indicated that the storage modulus, loss modulus and glass transition temperatures was initially decreased with the addition of micro-capsules from 0 to 6 wt% and increased on further increase of microcapsules up to 9 wt%. Finally, Cole–Cole plot has been drawn for identification of the nature of the proposed dental composites.

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Light-cured dental composites characterization by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175272 ◽

1990 ◽

Vol 48 (4) ◽

pp. 428-429

Author(s):

B. M. Culbertson ◽

M. L. Devinev ◽

E. C. Kao

Keyword(s):

Electron Microscopy ◽

Mechanical Analysis ◽

Service Performance ◽

Dental Composite ◽

Dental Composites ◽

Neat Resin ◽

Scanning Calorimetry ◽

Research Meeting ◽

Formulation Variables

The service performance of current dental composite materials, such as anterior and posterior restoratives and/or veneer cements, needs to be improved. As part of a comprehensive effort to find ways to improve such materials, we have launched a broad spectrum study of the physicochemical and mechanical properties of photopolymerizable or visible light cured (VLC) dental composites. The commercially available VLC materials being studied are shown in Table 1. A generic or neat resin VLC system is also being characterized by SEM and TEM, to more fully understand formulation variables and their effects on properties.At a recent dental research meeting, we reported on the differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) characterization of the materials in Table 1. It was shown by DSC and DMA that the materials are substantially undercured by commonly used VLC techniques. Post curing in an oral cavity or a dry environment at 37 to 50°C for 7 or more hours substantially enhances the cure of the materials.

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The Photoinitiators Used in Resin Based Dental Composite—A Review and Future Perspectives

Polymers ◽

10.3390/polym13030470 ◽

2021 ◽

Vol 13 (3) ◽

pp. 470

Author(s):

Andrea Kowalska ◽

Jerzy Sokolowski ◽

Kinga Bociong

Keyword(s):

Current Knowledge ◽

Biomechanical Properties ◽

Degree Of Conversion ◽

Dental Composite ◽

Polymerization Process ◽

Dental Composites ◽

Dental Resin ◽

Dental Resins ◽

Light Curing

The presented paper concerns current knowledge of commercial and alternative photoinitiator systems used in dentistry. It discusses alternative and commercial photoinitiators and focuses on mechanisms of polymerization process, in vitro measurement methods and factors influencing the degree of conversion and hardness of dental resins. PubMed, Academia.edu, Google Scholar, Elsevier, ResearchGate and Mendeley, analysis from 1985 to 2020 were searched electronically with appropriate keywords. Over 60 articles were chosen based on relevance to this review. Dental light-cured composites are the most common filling used in dentistry, but every photoinitiator system requires proper light-curing system with suitable spectrum of light. Alternation of photoinitiator might cause changing the values of biomechanical properties such as: degree of conversion, hardness, biocompatibility. This review contains comparison of biomechanical properties of dental composites including different photosensitizers among other: camphorquinone, phenanthrenequinone, benzophenone and 1-phenyl-1,2 propanedione, trimethylbenzoyl-diphenylphosphine oxide, benzoyl peroxide. The major aim of this article was to point out alternative photoinitiators which would compensate the disadvantages of camphorquinone such as: yellow staining or poor biocompatibility and also would have mechanical properties as satisfactory as camphorquinone. Research showed there is not an adequate photoinitiator which can be as sufficient as camphorquinone (CQ), but alternative photosensitizers like: benzoyl germanium or novel acylphosphine oxide photoinitiators used synergistically with CQ are able to improve aesthetic properties and degree of conversion of dental resin.

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Bi-axial flexural strength of resin based dental composites – Influence and reliability of the testing method configuration

Materials Technology ◽

10.1080/10667857.2021.1886664 ◽

2021 ◽

pp. 1-7

Author(s):

Naresh Kumar ◽

Fazal Ghani ◽

Muhammad Amber Fareed ◽

Samiya Riaz ◽

Zohaib Khurshid ◽

...

Keyword(s):

Flexural Strength ◽

Dental Composites ◽

Testing Method

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Commercial Dental Composite: Determination of Reaction Advancement and Study of the Migration of Organic Compounds

Polymers and Polymer Composites ◽

10.1177/096739110501300302 ◽

2005 ◽

Vol 13 (3) ◽

pp. 223-234

Author(s):

C. Sanglar ◽

M. Defay ◽

H. Waton ◽

A. Bonhomme ◽

S. Alamercery ◽

...

Keyword(s):

Artificial Saliva ◽

Aqueous Media ◽

Dental Composite ◽

Dental Composites ◽

Hydrophilic Monomer ◽

Methacrylate Monomers ◽

Urethane Dimethacrylate ◽

Hydrolysis Of

This work on organic dental composites was undertaken to determine the role of residual reactive methacrylate functions at the end of the photopolymerization cycle, and to investigate the fate of the residual monomers and oligomers in organic (ethanol) and aqueous (water and artificial saliva) media. The results show that all the methacrylate monomers present in dentine migrate into ethanol (about 1% (w/w)). In aqueous media on the other hand, only the most hydrophilic monomer (UDMA) migrates (0.05% (w/w)) into water and 0.03% into artificial saliva (pH = 9). This desorption in the three media is accompanied by the hydrolysis of monomers, leading to the formation of monohydrolyzed urethane dimethacrylate (UDMA) and bis-phenyl glycidyl dimethacrylate (BISGMA); UDMA and BISGMA are completely hydrolyzed in artificial saliva. The alkalinity of the milieu apparently favours the hydrolysis of methacrylate functions.

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An Elastic/Viscoplastic Finite Element Model for Predicting Polymerization Stresses in Light-Activated Dental Composites

Advances in Bioengineering ◽

10.1115/imece2003-43789 ◽

2003 ◽

Author(s):

Gayle A. Laughlin ◽

John L. Williams ◽

J. David Eick

Keyword(s):

Finite Element ◽

Element Model ◽

Numerical Approach ◽

Mechanical Analysis ◽

Dental Composite ◽

Time Dependent ◽

Dental Composites ◽

Cavity Preparation ◽

Constitutive Parameters ◽

Perzyna's Theory

The purpose of this paper is to apply a finite deformation, elastic/viscoplastic approach to predict curing stresses in three light-cured dental composites, using Perzyna’s theory. Time-dependent constitutive parameters were obtained from mercury dilatometry, dynamic mechanical analysis and constrained shrinkage strerss testing. The numerical approach was verified by using the results of an experiment on a simple aluminum tooth model of a cavity preparation that was bulk-filled with light-cured dental composite restorative materials. The numerically predicted strain patterns were similar to those seen experimentally for the three different dental composites.

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