OBJECTIVES This study aimed to assess the effect of 38% carbamide peroxide on the microleakage of class V cavities restored with either a silorane-based composite or two methacrylate-based composites. MATERIALS AND METHODS A total of 96 class V cavities were prepared on the buccal surface of extracted human teeth with both enamel and dentin margins and were randomly assigned into three groups...

This study investigated the effects of in-office tooth whiteners on the hardness of hybrid (Spectrum TPH), polyacid-modified (Dyract AP), PRG (Reactmer) composites and a resin-modified glass ionomer cement (Fuji II LC). Twenty-seven specimens of each material were fabricated, randomly divided into three groups of nine and treated as follows--Group 1: stored in distilled water at 37 degrees C fo...

OBJECTIVE To evaluate the effect of home-use bleaching agent containing 16% Carbamide Peroxide (CP) and in-office bleaching agent with 38% Hydrogen Peroxide (HP) on surface micro-morphology of enamel. STUDY DESIGN An experimental study. PLACE AND DURATION OF STUDY The discs were prepared at Material Engineering Department of NED University of Engineering and Technology, Karachi, and surface...

Objective To compare and evaluate the efficacy of tooth bleaching with prior application two different desensitizing agents such as sodium fluoride 5% potassium nitrate. Materials methods A total 108 extracted human maxillary central incisors were stained in black coffee solution stored artificial saliva for colour stabilization. The specimens randomly divided into three groups (n = 36) accordi...

OBJECTIVES The aim of this study was to evaluate the effect of different in-office and home bleaching gels on the surface mercury levels of dental amalgam. METHODS Sixty disk-shaped amalgam specimens (GS-80, SDI- Australia) were prepared and randomly divided into the following treatment groups: 1. Distilled water (control); 2. 15% home-bleach carbamide peroxide (Opalescence PF, Ultra dent, US...

During tooth bleaching abrasive dentifrices might change the outer superficial enamel. The aim of this in vitro study was to evaluate the roughness of human enamel exposed to a 10% carbamide peroxide bleaching agent at different times and submitted to different superficial cleaning treatments. The study consisted of 60 sound human enamel slabs, randomly assigned to different treatment groups: G...

Fears that the dentist-supervised use of a product that contains carbamide peroxide and that emits hydrogen peroxide may not be safe from the viewpoints of toxicity and cancer risk were engendered by unrealistic animal tests. These fears prompted the UK Government Departments of Trade and Industry (DTI) and of Health (DOH) to try to prohibit the marketing of Opalescence (manufactured by Ultrade...

OBJECTIVE The purpose of this study was to evaluate, using scanning electron microscopy (SEM), the morphological and structural changes of the enamel induced by three bleaching agents namely old McInnes solution, modified McInnes solution and 10% carbamide peroxide gel at different time intervals. MATERIALS AND METHODS Fifteen freshly extracted noncarious human central incisors with intact en...