statement of problem: mechanical failure of ceramic materials is controlled by brittle fracture, mostly occurred in tension. in 3-unit all-ceramic fpds the connector area is considered to be at fracture risk because of tensile stress concentrations. purpose: the aim of this fe analysis was to evaluate the effect of taper on stress distribution in all-ceramic fpds. materials and methods: in this...

OBJECTIVE To test the following hypotheses: (1) degree of conversion (DC) and polymerization stress (PS) increase with composite temperature (2) reduced light-exposure applied to pre-heated composites produces similar conversion as room temperature with decreased PS. METHODS Composite specimens (diameter: 5mm, height: 2mm) were tested isothermally at 22°C (control), 40°C, and 60°C using light...

BACKGROUND AND AIM OF THE STUDY In-vitro studies on the ATS heart valve have indicated that valve opening is less in an expanding conduit than in a straight conduit. METHODS Bileaflet valve behavior was studied using a new computational fluid-structure interaction model. A three-dimensional model of the ATS valve was studied in two geometries, simulating the valve in a geometry with sudden ex...

Objective The aim of this study was to examine the properties of fiber-reinforced composite and stainless steel twisted retainers for orthodontic retention. Methods Three different span lengths (5.0, 8.0, and 14.0 mm) of fiber-reinforced composite were investigated. The three fiber-reinforced composite retainer groups were subdivided according to the storage condition (dry and wet), resulting...

In this study, stress distributions on dental implants made of functionally graded biomaterials (FGBM) are investigated numerically. The implant body is considered to be subjected to axial compression loads. Numerical problem is assumed to be 2D, and ANSYS commercial software is used for the analysis. The cross section of the implant thread varies as varying the height (H) and the width (t) of ...

In this study, stress distributions on dental implants made of functionally graded biomaterials (FGBM) are investigated numerically. The implant body is considered to be subjected to axial compression loads. Numerical problem is assumed to be 2D, and ANSYS commercial software is used for the analysis. The cross section of the implant thread varies as varying the height (H) and the width (t) of ...

As wood shrinks during the drying process, various stresses may develop and cause surface and internal checking. The aim of this study was to systematically investigate the effect of the drying temperature, relative humidity, and specimen thickness on the contraction stress in elm wood (Ulmus pumila L.) specimens during drying. The contraction stress was used as an indirect indicator of drying ...