INTRODUCTION This in vitro study evaluated the influence of composite thickness (with or without fiber reinforcement) on fracture resistance of direct restorations in endodontically treated teeth. METHODS AND MATERIALS Fifty-six intact human premolars were chosen and randomly divided into four groups (n=14). After preparation of a mesio-occluso-distal (MOD) cavities and cusp reduction, the te...

T alon cusp refers to a cusp-like structure project ing from the cingulum area of a maxillary or mandibular anterior tooth. Shafer et al. and Mellor and Ripa reported that talon cusp is uncommon and occurs in maxillary and mandibular permanent incisors. Most cases of the anomaly have been reported in the permanent dentition. Ninety percent of the talon cusps occur in anterior permanent teeth, a...

OBJECTIVES Based on a maxillary premolar restored with laminate veneer and using the 3-D finite element analysis (FEA) and μCT data, the aim of this study was to evaluate the influence of different types of buccal cusp reduction on the stress distribution in the porcelain laminate veneer and in the resin luting cement layer. METHODS Two 3-D FEA models (M) of a maxillary premolar were built fr...

Gemination with talon cusps is an uncommon morphologic dental anomaly, characterized by the formation of clinically wide tooth that can cause significant aesthetic and clinical problems including esthetic impairment, pain, caries susceptibility, and tooth crowding. These morphological dental anomalies have specific treatment needs due to the abnormal morphology and need virtuous radiologic diag...

A long series of polar patches was observed by ionosondes and an all-sky imager during a disturbed period (Kp ˆ 7and IMF Bz < 0). The ionosondes measured electron densities of up to 9 ́ 10 m in the patch center, an increase above the density minimum between patches by a factor of 4.5. Bands of F-region irregularities generated at the equatorward edge of the patches were tracked by HF radars. Th...

Global positioning system scintillation and total electron content (TEC) data have been collected by ten specialized GPS Ionospheric Scintillation and TEC Monitors (GISTMs) of the Canadian High Arctic Ionospheric Network (CHAIN). The phase scintillation index σ8 is obtained from the phase of the L1 signal sampled at 50 Hz. Maps of phase scintillation occurrence as a function of the altitude-adj...