Different materials and techniques are used in dental wear restoration with the objective of increasing teeth resistance, and providing an aesthetic appearance. The aim of this study was to compare the fracture resistance of amalgam and posterior composite in abrasioned premolar and molar teeth. In this study, 60 carries and restoration- free human permanent mandibular premolar and molar teeth,...

OBJECTIVE One of the major problems of all ceramic restorations is their probable fracture against the occlusal force. The aim of the present in-vitro study is was to compare the effect of two marginal designs (chamfer & shoulder) on the fracture resistance of zirconia copings, CERCON (CAD/CAM). MATERIALS AND METHODS This in vitro study was done with single blind experimental technique. One s...

South Africa has numerous thermal springs that represent topographically driven meteoric water migrating along major fracture zones. The temperature (40-70°C) and pH (8-9) of the thermal springs in the Limpopo Province are very similar to those of the low salinity fracture water encountered in the South African mines at depths ranging from 1.0 to 3.1 km. The major cation and anion composition o...

Objective: To study the effect of both laser and ultrasound radiation on bone fracture healing process. Materials and Methods: Nd:YAG laser (1064 nm wavelength, 135 mW power, 16 joules energy) and ultrasound (1 MHz frequency, 50 mW/cm2 power intensity) were used in this work. Fifteen mature, male, albino rats, were divided into three groups and subjected to a partial fracture on the lateral asp...

Reactive fluid-flow experiments in fractures subjected to normal stress suggest the potential for either increased or decreased permeability resulting from fracture-surface dissolution. We present a computational model that couples mechanical deformation and chemical alteration of fractures subjected to constant normal stress and reactive fluid flow. The model explicitly represents micro-scale ...

Abstract Proppant crushing and embedment in hydraulically-induced fractures is a major drawback to the recovery of unconventional oil/gas geothermal energy production. This study provides grain-scale analysis fracture evolution mechanisms proppant crushing, rock damage during embedment, influence realistic reservoir/fracture fluid on behaviour packs subjected in-situ stresses using discrete ele...

In the stratified ocean, vertical motions arise from both adiabatic and diabatic mechanisms. Diapycnal advection is the vertical component of flow across an isopycnal surface which occurs when mixing produces a divergent flux of buoyancy. Buoyancy forcing of the lateral flow by vortex stretching occurs when diapycnal advection rates vary with depth. Microstructure observations of enhanced turbu...

INTRODUCTION: Improper resection depth in the surgical correction of cam-type femoroacetabular impingement (FAI) has been identified as the most common reason for revision hip arthroscopy [1]. Under-resection fails to address patient symptoms and results in the need for revision arthroscopy [1], while over-resection may lead to iatrogenic femoral neck fracture, loss of the normal joint suction ...

Time-resolved interferometry, surface light-scattering imaging, and optical microscopic imaging have been developed and applied to research on amorphous and multicrystalline films upon intense pulsed excitation. Nanosecond interferometry of neat polystyrene film gives interesting expansion dynamics followed by complete recovery. Femtosecond surface light-scattering imaging reveals the roughenin...