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Mechanical properties of dental composite resins containing nanodiamond of different diameters

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Journal of Beijing Institute of Technology 2012年第1期21卷 19-22页

作者：楚亚卿仝毅张同来黄风雷 School of Mechatronical Engineering Beijing Institute of Technology

In order to investigate the effect of nanodiamond （ND） on the mechanical properties of dental composite resins, bisphenol-A-glycidyl dimethacrylate （ Bis-GMA ）, triethylene glycol dime- thacrylate （ TEGDMA）, barium glass （BG） powder, DL-camphoroquinone （CQ） and dimethylamin- oethylmethacrylate （DMAEMA） were mixed as the matrix for the experiments. NDs of three diame- ters （ 100 nm, 220 nm, 500 nm） modified with 3-（trimethoxysilyl） propyl methacrylate （γ-MPS） were added to the mixture separately in 0. 2% to get test samples. The fiexural strength and elastic modulus of these samples and the mixture without ND （as the reference group, RG） were characterized with standard specification tests. Results reveal that the mechanical properties and elastic modulus of resins containing 220 nm ND （ R-220 ） and 500 nm ND （ R-500 ） were significantly different from those of RG. R-500 had the highest flexural strength and elastic modulus （ by average data）, and all of its five specimens were found to have mean flexural strength values greater than the minimum value （80MPa） prescribed by ISO 4049： 2000. Different sizes of diamonds have different effects on mechanical properties of dental composite resins, and the performances of 220 nm and 500 nm diamonds are better than that of 100 nm diamond.

关键词： dental composite nanodiamond mechanical properties

Micromechanical interlocking-inspired dendritic porous silicabased multimodal resin composites for the tooth restoration

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Nano Research 2024年第10期17卷 9065-9077页

作者： Hongyan Chen Junjun Wang Shi Yin Ruili Wang Xinquan Jiang Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Material Science and EngineeringDonghua UniversityShanghai 201620China Shanghai Engineering Research Center of Advanced dental Technology and Materials Shanghai Key Laboratory of StomatologyShanghai Research Institute of StomatologyNational Clinical Research Center for Oral DiseasesShanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineShanghai 200011China

Porous silica particles have shown great potential application as reinforcing fillers in the field of dentistry due to their ability to construct the micromechanical interlocking effect at filler-matrix ***,how to accurately regulate the pore structure,especially the pore size,to increase the degree of the micromechanical interlocking and the performance of materials remains a ***,we have proposed a facile self-assembly process to synthesize dendritic porous silica with tunable pore sizes(DPS-x)by adjusting the chain-length of the alcohols in the *** mechanism of nucleation-growth is further put *** results indicate that the pore size of DPS-x indeed affects the mechanical property of composites,where the DPSpen particles with intermediate pore size are chosen as the optimal reinforcing *** bimodal and multimodal filler formulations are further established to address the loading limitation of unimodal DPS-pen(46 wt.%).In virtue of the closepacked structure of identical spheres,the particle sizes of secondary silica embedded into the maximally loaded bimodal D3S7 composite(DPS-pen:Si430=30:70,w/w)are theoretically calculated without *** all formulations,the developed multimodal D3S7+Si178+Si90 filler exhibits superior mechanical properties,the lowest shrinkage,and high polymerization conversion for dental composites,along with satisfied waster sorption and solubility,and good biocompatibility in vitro and in vivo,which are comparable to commercial composite Z350 XT(3M,USA).These DPS-x particles and their multimodal fillers can also be applied to other polymer-based biomaterials.

关键词： porous silica pore size multimodal filler dental composite physicochemical properties biosafety

Application of digital image correlation to full-field measurement of shrinkage strain of dental composites

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第1期14卷 1-10页

作者： Jian-ying LI Andrew LAU Alex S. L. FOK Minnesota dental Research Centre for Biomaterials and Biomechanics School of Dentistry University of Minnesota Minneapolis MN 55455 USA

Objectives： Polymerization shrinkage of dental composites remains a major concern in restorative dentistry because it can lead to micro-cracking of the tooth and debonding at the tooth-restoration interface. The aim of this study was to measure the full-field polymerization shrinkage of dental composites using the optical digital image correlation （DIC） method and to evaluate how the measurement is influenced by the factors in experiment setup and image analysis. Methods： Four commercial dental composites, Premise Dentine, Z 100, Z250 and Tetric EvoCeram, were tested. composite was first placed into a slot mould to form a bar specimen with rectangular-section of 4 mmx2 mm, followed by the surface painting to create irregular speckles. Curing was then applied at one end of the specimen while the other part were covered against curing light for simulating the clinical curing condition of composite in dental cavity. The painted surface was recorded by a charge-coupled device （CCD） camera before and after curing. Subsequently, the volumetric shrinkage of the specimen was calculated with specialist DIC software based on image cross correlation. In addition, a few factors that may influence the measuring accuracy, including the subset window size, speckle size, illumination light and specimen length, were also evaluated. Results： The volumetric shrinkage of the specimen generally decreases with increasing distance from the irradiated surface with a conspicuous exception being the composite Premise Dentine as its maximum shrinkage occurred at a subsurface distance of about 1 mm instead of the irradiated surface. Z100 had the greatest maximum shrinkage strain, followed by Z250, Tetric EvoCeram and then Premise Dentine. Larger subset window size made the shrinkage strain contour smoother. But the cost was that some details in the heterogeneity of the material were lost. Very small subset window size resulted in a lot of noise in the data, making it difficult to discern the g

关键词： Image correlation dental composite Polymerization shrinkage Depth of cure

The effect of temperature on the wear behaviour of dental composites

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Biosurface and Biotribology 2022年第4期8卷 329-336页

作者： Joseph A.Arsecularatne Serena Tran Mark J.Hoffman School of Materials Science and Engineering UNSW SydneySydneyNew South WalesAustralia School of Mechanical and Manufacturing Engineering UNSW SydneySydneyNew South WalesAustralia School of Engineering University of NewcastleCallaghanNew South WalesAustralia

Despite numerous published studies on the wear of dental composites,few have considered the influence of temperature on the two-body wear ***,no previous work has considered the influence of temperature on dominant wear mecha-nisms during the consumption of hot substances,hence the focus of this ***-rocating wear tests were carried out at varying artificial saliva lubricant temperatures(37 and 57℃)and material loss was quantified using *** wear tracks were analysed using FIB/SEM/*** reveal that the wear rate of a dental composite can significantly increase with temperature,with fatigue/delamination and ploughing acting as dominant mechanisms.

关键词： dental composite temperature tribological performance wear mechanism

Mechanical properties and biocompatibility of polymer infiltrated sodium aluminum silicate restorative composites

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Journal of Advanced Ceramics 2017年第1期6卷 73-79页

作者： Huining WANG Bencang CUI Jing LI Shu LI Yuanhua LIN Deping LIU Ming LI Department of Periodontology School and Hospital of Stomatology Shandong Provincial Key Laboratory of Oral Tissue Regeneration Shandong University Jinan 250012 China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China Department of Cardiology Beijing Hospital National Center of Gerontology Beijing 100730 China

A new type of polymer-infiltrated-ceramic-network composites (PICNs) was fabricated by infiltrating methacrylate-based monomers into partially sintered porous *** mechanical properties (flexural strength,flexural modulus,elastic modulus,Vickers hardness,fracture toughness) were investigated and compared with that of the natural tooth and common commercial CAD/CAM *** results indicated that sintering temperature and corresponding density of porous ceramics have an obvious influence on the mechanical properties,and PICNs could highly mimic the natural tooth in mechanical *** biocompatibility experiments evaluated through in vitro cell attachment and proliferation of BMSCs showed good *** mechanical properties and biocompatibility confirmed that PICN could be a promising candidate for CAD/CAM blocks for dental restoration.

关键词： dental composite polymer-infiltrated-ceramic-network composites (PICNs) CAD/CAM blocks mechanical properties biocompatibility

THE INFLUENCE OF SHRINKAGE AND MOISTURE DIFFUSION ON IDEALIZED TOOTH STRUCTURE INVOLVING DEBONDING DAMAGE

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Acta Mechanica Solida Sinica 2005年第2期18卷 110-122页

作者： FanJianping TangChak-Yin DepartmentofMechanics HuazhongUniversityofScienceandTechnologyWuhan430074China DepartmentofIndustrialandSystemsEngineering TheHongKongPolytechnicUniversityHongKongChina

This study highlights the joint effect of early polymerization shrinkage and long-term moisture diffusion on the behavior of the restoration-tooth structure. The interphase debonding between particle and polymer resin in dental composite is taken into account by introducing the damage variable. The idealized model is designed and constructed for representing the restorationtooth structure, which consists of enamel, dentin, composite and interphase, each considered as homogenous material. The simulation is carried out using the general-purpose finite element software package, ABAQUS incorporated with a user subroutine for definition of damaged material behavior. The influence of Young's moduli of composite and interphase on stress and displacement is discussed. The compensating effect of water sorption on the polymerization shrinkage is examined with and without involving damage evolution. A comparison is made between the influence of hyper-, equi- and hypo-water sorption. Interfacial failure in the specific regions as well as cuspal movement has been predicated. The damage evolving in dental composite reduces the rigidity of composite, thus in turn reducing consequent stress and increasing consequent displacement. The development of stresses at the restoration-tooth interface can have a detrimental effect on the longevity of a restoration.

关键词： polymerization shrinkage water sorption restoration-tooth structure finite element method dental composite stress distribution displacement distribution

Effect of Filler Ratio on Properties of Nano-hydroxyapatite/SiO2 Based Bioactive dental Resin composites

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Effect of Filler Ratio on Properties of Nano-hydroxyapatite/...