OBJECTIVE The aim of the present study was to assess the hypothesis that the efficiency of vital tooth bleaching depends on the concentration of carbamide peroxide agents. METHODS The front teeth of 30 subjects were bleached at home with 10%, 17% or 0% (control) carbamide peroxide for 1 week in a double-blind study design. Tooth shades were determined in the LCH color space employing a visual...

OBJECTIVE To investigate the effect of different intracoronal bleaching methods on the shear bond strength and site of failure of ceramic brackets. MATERIALS AND METHODS Sixty freshly extracted human maxillary incisors were randomly divided into four groups (n = 15). Endodontic access cavity was prepared and root canals were filled, root fillings were removed 2mm apical to the cementoenamel j...

For many years, at-home whitening has been used with great success and produces some of the most satisfying results of all dental procedures. Historically, the most common procedure used was a custom-fabricated tray loaded with a 10% carbamide peroxide gel that was worn overnight. Today, many manufacturers offer higher concentrations (15% and 20% carbamide peroxide) for faster results. Regardle...

Objectives. Extra radicular diffusion of hydrogen peroxide associated with intracoronal teeth bleaching was evaluated. Methods. 108 intact single rooted extracted mandibular first premolars teeth were selected. The teeth were instrumented with WaveOne system and obturated with gutta percha and divided into four groups (n = 27) according to the bleaching materials used. Each main group was divid...

This in vitro study evaluated the shear bond strength (SBS) of dentin treated with two 10% carbamide peroxide bleaching agents 15 days after bleaching and storage in artificial saliva. Dentin fragments were randomly divided into 3 groups (n = 20) for the treatment with the two different bleaching agents (Rembrandt 10% or Opalescence 10%) or with a placebo agent, applied to the tooth surface for...

This study investigated the effect of 16% carbamide peroxide (Whiteness Perfect/FGM) on the Vickers microhardness and flexural strength of the restorative composites Filtek Z100 (hybrid), Filtek Z350 (nanofill), Brilliant (micro-hybrid) and Opallis (micro-hybrid). Disc-shaped (4x2 mm; n=5) and bar-shaped (12x2x1 mm; n=10) specimens of each restorative material were randomly divided into 2 group...

BACKGROUND Auxiliary power sources (LED and laser) are used in in-office teeth bleaching techniques to accelerate the redox reaction of the whitening gel to increase ease of use, to improve comfort and safety, and to decrease the procedure time. OBJECTIVE The aim this study is to evaluate the efficiency of the teeth whitening procedures performed with hydrogen peroxide and carbamide peroxide,...

A number of "high power" in-office bleaching products have recently been re-introduced into the market. The use of such strong oxidizing agents has raised questions as to possible adverse effects on tooth structure and restorative materials. This study evaluated the effects of 35% carbamide peroxide (Opalescence Quick) and 35% hydrogen peroxide (Opalescence Xtra) on the surface finish of four t...

OBJECTIVE To compare the effects of three antioxidants (sodium ascorbate, sodium ascorbate combined with a surfactant, and catalase) on the microleakage of composite resin restorations after external tooth bleaching with 10% carbamide peroxide. MATERIALS AND METHODS Buccal cavities were prepared on the surface of 60 intact premolars, which were randomly divided into six groups. All cavities w...

Dental bleaching occurs due to an oxidation reaction between the bleaching agents and the macromolecules of pigments in the teeth. This reaction is unspecific and the peroxides can also affect the dental matrix causing mineral loss. On the other hand, recent studies have suggested that the thickener agent carbopol can also cause mineral loss. Thus, the objective of this study was to evaluate in...