Rapid advances are taking place to develop hydrogels of high stretchability and toughness, but fatigue fracture has not been studied for any hydrogels. This negligence hinders the development of hydrogels and their applications. Herewe initiate a study of fatigue fracture of hydrogels.We choose polyacrylamide hydrogel as a model material. To place fatigue fracture in context, we apply monotonic...

The purpose of this study was to conduct static load-bearing tests on 4-unit Y-TZP all-ceramic fixed partial denture (FPD) frameworks with different cross-sectional areas and forms to evaluate the influence of connector design on fracture load. Each of the central, mesial and distal connectors was prepared with one of 2 different cross-sectional areas and one of 3 different forms (one circular ...

fast fracture is one of the major failure modes in brittle polymers. generally, crack growth in these polymers may occur under combined tensile-shear loading. however, the fracture test data reported previously for some dental restorative resins can not be predicted by using the available fracture criteria.in this paper, a modified fracture criterion is used for estimating the fracture load for...

the purpose of this ex- vivo study was to evaluate the fracture resistance of simulated immature teeth, obturated with gutta-percha or resilon and reinforced by either composite resin or fiber post.eighty-four human maxillary incisors were divided into seven groups (n=12). teeth in all groups were prepared until peeso #5 (1.5mm) could be passed through the apex. root ends received 4mm of mta pl...

introduction: the resistance to fracture of endodontically treated teeth restored with esthetic post systems has not been extensively researched. this in vitro study compared the fracture patterns of endodontically treated teeth with esthetic post systems with different analysis methods. materials and methods: a total of 26 recently extracted human maxillary central incisors were decoronated an...

Mechanisms of femoral fracture of the condyles and shaft were experimentally investigated through controlled knee impact ofdenuded femurs in six human cadavers. High-speed movies recorded knee joint compression, femoral displacements and deformation, and fracture initiation. Fracture initiated at 10.6 + 2.7 kN knee load after 1.3 + 0.1 cm ofknec joint compression for a 10.1 kg rigid impact at 1...

This study evaluated the effect of zirconia framework design on fracture load of implant-supported zirconia-based prostheses after thermal cycling and mechanical loading. Three different zirconia framework designs were investigated: uniform-thickness (UNI), anatomic (ANA), and supported anatomic (SUP) designs. Each framework was layered with feldspathic porcelain (ZAC group) or indirect composi...

INTRODUCTION: Finite element (FE) models for predicting proximal femoral fracture load are useful for research related to the prevention of hip fracture. CT scan-based non-linear FE models have been shown to predict proximal femoral fracture load precisely in vitro. However, if these models are to be used in vivo, we need to know the effect of using CT scan data obtained in situ instead of in v...

BACKGROUND Among the millions of people suffering from a hip fracture each year, 20% may sustain a contralateral hip fracture within 5 years with an associated mortality risk increase reaching 64% in the 5 following years. In this context, we performed a biomechanical study to assess the performance of a hip fracture preventing implant. METHODS The implant consists of two interlocking peek ro...

Objective In this study, marginal and internal misfit and fracture load with and without thermal-mechanical aging (TMA) of monolithic ZLS and lithium disilicate (LDS) crowns were evaluated. Material and methods Crowns were milled using a computer-aided design/computer-aided manufacturing system. Marginal gaps (MGs), absolute marginal discrepancy (AMD), axial gaps, and occlusal gaps were measu...