In response to the informative article written by Dr. Omar El-Mowafy in the December 2007/January 2008 issue of the JCDA,1 I would like to offer some comments from a different perspective and with different conclusions. The article suggested that the tissue of a 25-year-old, otherwise healthy gentleman was inf lamed around porcelain-fused-to-metal (PFM) crowns on both maxillary central incisors...

The purpose of this study was to compare the longevity of crowns versus large multisurface restorations in posterior teeth. The investigation used the treatment database at Virginia Commonwealth University School of Dentistry. The inclusion criteria for the final data set used for analysis were: only one restored tooth per patient, premolars with three or more restored surfaces, molars with fou...

The effect of dentin pretreatment with Desensitizing Paste containing 8% arginine and calcium carbonate on the retention of zirconium oxide (Y-TZP) crowns was tested. Forty molar teeth were mounted and prepared using a standardized protocol. Y-TZP crowns were produced using computer-aided design and computer-aided manufacturing (CAD-CAM) technology. The 40 prepared teeth were either pretreated ...

The development of different materials for the use in posterior areas for aesthetic monolitic crowns has been a challenge in dental technology. The goal of this study was to develop 3D posterior teeth covered with complete aesthetic monolitic crowns and to compare the stress distributions under loads, revealing the effect of various materials on the biomechanical performance of the crowns. For ...

A leucite-reinforced glass ceramic material (IPS-Empress) was developed for clinical use in Zurich. A prospective clinical study of these laboratory-made all-ceramic crowns revealed encouraging result with an estimated 2-year survival rate of 95%. The aim of the present study was to determine the clinical behavior during a longer period of observation with respect to a possible fatigue fracture...

The mechanisms contributing to failure of full dental ceramic crowns under occlusal loads were studied using a unique optical approach. Model specimens comprising triple-layered crowns (veneer, core and substrate) were developed with both flat and curved occlusal surfaces and then subjected to simulated quasi-static occlusal loading using a spherical indenter. Deformation within the specimens d...

OBJECTIVE This retrospective study aimed to analyse the failure rate of the facings of double crown-retained dentures. MATERIALS AND METHODS The clinical reports of 575 patients, who received double crown-retained removable dentures with a total of 1807 double crowns between 1984 and 2007, were included in the study. The 575 prostheses were attached to telescopic crowns using a friction fit (...

BACKGROUND The aim of this study was to evaluate the biomechanical response of the peri-implant bone to standard, short-wide, and double mini implants replacing missing molar supporting either hybrid ceramic crowns (Lava Ultimate restorative) or full-metal crowns under two different loading conditions (axial and off-axial loading) using strain gauge analysis. METHODS Three single-molar implan...

PURPOSE The purpose of this study was to compare the fit of cast gold crowns fabricated from the conventional and the digital impression technique. MATERIALS AND METHODS Artificial tooth in a master model and abutment teeth in ten patients were restored with cast gold crowns fabricated from the digital and the conventional impression technique. The forty silicone replicas were cut in three se...

PURPOSE The aims of this randomized-controlled clinical trial were to compare marginal and internal adaptation of all-ceramic crowns fabricated with CAD/CAM and heat-pressed (HP) techniques before luting and to evaluate the clinical outcomes at baseline and at 6, 12, and 24 months after luting. MATERIALS AND METHODS Fifteen CAD/CAM (CC) and 15 HP all-ceramic crowns were placed in 15 patients....