p0010 While fracture nonunions may represent a small percentage of the traumatologist’s case load, they can account for a high percentage of a surgeon’s stress, anxiety, and frustration. Arrival of a fracture nonunion may be anticipated following a severe traumatic injury, such as an open fracture with segmental bone loss, but may also appear following a low-energy fracture that seemed destined...

Objective To determine the ideal working area for a simple transverse fracture line treated with a bridge plate. Methods A 2-D finite element analysis of a hypothetical femur was performed for the quantitative evaluation of a large-fragment titanium alloy locking plate based on the precept of relative stability in a case of a simple transverse diaphyseal fracture. Two simulations (one case of...

Temperature dependent fracture properties of NiTi-based Shape Memory Alloys (SMAs), within the pseudoelastic regime, were analyzed. In particular, the effective Stress Intensity Factor (SIF) was estimated, at different values of the testing temperature, by a fitting of the William's expansion series, based on Digital Image Correlation (DIC) measurements. It was found that temperature plays an i...

OBJECTIVES This study compared the fracture strength and survival rate of endodontically treated crowned maxillary incisors with approximal class III cavities and different core build-ups. METHODS Sixty-four caries free human maxillary central incisors were selected for standardized size and quality, endodontically treated and prepared with approximal cavities 3mm in diameter. Group 1 was res...

The application of peel tests for the measurement of adhesive fracture toughness of metal-polymer laminates is reviewed and the merits of a mandrel peel method are highlighted. The mandrel method enables a direct experimental determination of both adhesive fracture toughness (GA) and the plastic bending energy (GP) during peel, whilst other approaches require a complex calculation for GP. In th...

OBJECTIVES The purpose of this in vitro study was to compare the marginal adaptation and fracture resistance of a zirconia-based all-ceramic restoration with two preparation designs. MATERIALS AND METHODS Twenty-four mandibular premolars were randomly divided into two groups (n=12); the conventional group received a peripheral shoulder preparation and the modified group received a buccal shou...

The mechanical and electrochemical behavior of the surface oxides of CoCrMo and Ti6Al4V alloys during fracture and repassivation play an important role in the corrosion of the taper interfaces of modular hip implants. This behavior was investigated in one group of CoCrMo and Ti6Al4V alloy samples passivated with nitric acid and another group coated with a novel TiN/AlN coating. The effects of m...

The aim of this in vitro study was to evaluate the fracture load and marginal accuracy of crowns made from a shrinkage-free ZrSiO4 ceramic cemented with glass-ionomer or composite cement after chewing simulation. Thirty-two human mandibular molars were randomly divided into two groups. All teeth were prepared for and restored with shrinkage-free ZrSiO4 ceramic crowns (Everest HPC, KaVo). The cr...

BACKGROUND Posts and cores are often required for restoration of pulpless teeth and to provide retention and resistance for a complete crown, but conventional posts may increase the root fracture. OBJECTIVE This study was performed to compare the root fracture resistance of extracted teeth treated with different fibers reinforced with composite posts and treated teeth with conventional post a...