Comparative efficacy and tolerability of two direct-to-consumer tooth whitening systems.

PURPOSE: To compare the clinical response of two self-directed vital bleaching systems under market use conditions. MATERIALS AND METHODS: A randomized, parallel-group clinical trial was conducted. A total of 20 healthy adults were randomized to either a 6.0% hydrogen peroxide strip-based bleaching system or a combination system involving a 10% carbamide peroxide gel in a stock tray along with an anticavity whitening dentifrice and after-bleaching whitening mouthrinse. Only the maxillary arch was bleached over a 14-day period. Subjects were evaluated at 3, 8 and 15 days. Efficacy was measured objectively using digital image analysis to derive individual color parameters (L*a*b*) and overall color change (deltaE*). RESULTS: After 14 days, the adjusted mean reduction in yellow (Ab*) was -2.23 +/- 0.157 for the whitening strips compared to -0.97 +/- 0.188 for the combination system. This represented a highly statistically significant (P< 0.0001), two-fold superior reduction in yellowness for the whitening strip group compared to the marketed control. Similar results were seen for other color parameters, with the whitening strip group exhibiting two-fold color improvement relative to the tray/dentifrice/rinse combination. With respect to tolerability, tooth sensitivity and oral irritation were the most common findings. Considering event duration and severity, median bleaching tolerability severity-days scores were 0.07 and 0.58 for the strip and combination systems respectively, with these treatments differing statistically (P= 0.04 1) favoring the whitening strips.

A randomized clinical trial comparing a novel 5.3% hydrogen peroxide whitening strip to 10%, 15%, and 20% carbamide peroxide tray-based bleaching systems.

A randomized and controlled, parallel-group clinical trial compared the whitening benefits of a novel 5.3% hydrogen peroxide bleaching strip to 10%, 15%, and 20% carbamide peroxide tray-based bleaching systems. A total of 36 healthy adults were randomized to a 14-day regimen in which both arches were whitened for 1 hour per day in the whitening-strip group or 2 hours per day in the tray groups. Efficacy was measured objectively using digital images of the anterior teeth at baseline and after 14 days of treatment. Overall tooth color (L*a*b*) was derived from individual pixel values, and then mean levels of delta b*, delta L*, and composite color (delta E*) were compared using analysis of covariance. After 14 days of treatment, all groups experienced a greater than 1-unit mean improvement in delta b*, delta L*, and delta E* relative to baseline. For the primary study variable, reduction of yellow (delta b*) outcomes after 14 hours of using the experimental strip were comparable to those observed with the 10% tray group after 28 hours of use. These two treatment groups did not differ statistically with respect to any of the color measurements used in this study. For the tray groups, there was a reasonable dose relationship for the primary end point, delta b*, with the 15% and 20% tray groups averaging 17% and 68% improvements in yellow, respectively, over the 10% group. Except for the 20% carbamide peroxide system, where sensitivity was relatively common, all test products were well tolerated. In this first comparative evaluation vs marketed controls, use of the whitening strips twice daily for 14 days yielded a highly significant improvement in tooth color vs baseline.

Vital tooth whitening with a novel hydrogen peroxide strip system: design, kinetics, and clinical response.

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. Regardless of the peroxide concentration used, the custom tray delivery system has remained essentially the same. Recently, a trayless whitening system was developed that does not require any prefabrication or gel loading. The new delivery system is a thin, conformable strip precoated with an adhesive hydrogen peroxide gel. Each preloaded strip is presented on a backing liner. To use the strip, it is peeled off of the backing liner and applied to the facial surfaces of the anterior teeth. Each strip is worn for 30 minutes, removed, and discarded. The strip holds the gel in place for sufficient time to allow the peroxide to intrinsically and extrinsically whiten the teeth. The highly flexible strips conform intimately to the tooth surface and provide a uniform, controlled application of the peroxide gel.

Objective quantification of plaque using digital image analysis.

Dental plaque is the precursor to many oral diseases (e.g. gingivitis, periodontitis, caries) and thus its removal and control are an important aspect of oral hygiene. Many of the oral care products available today remove or inhibit the growth of dental plaque. Historically, the antiplaque efficacy of products was measured in blinded clinical trials where the amount of plaque on teeth is assessed via subjective visual grading with predefined scales such as the Turesky index. The ability of the examiner to consistently apply the index over time and the sensitivity of the scales often leads to large, expensive clinical trials. The present invention is an automatic measurement of plaque coverage on the facial surfaces of teeth using a digital image analysis technique. Dental plaque disclosed with fluorescein is digitally imaged under long-wave ultraviolet light. Ultraviolet illumination of fluorescein-disclosed plaque produces an image where the pixels of the image can be categorically classified based on color into one of five classes: teeth; plaque; gingiva; plaque on gingiva, or lip retractors. The amount of plaque on teeth can be determined by summation of the number of plaque pixels. The percent coverage is calculated from the number of plaque pixels and teeth pixels in the image. The digital image analysis of plaque allows facial plaque levels to be precisely measured (RSD = 3.77%). In application, the digital image analysis of plaque is capable of measuring highly significant plaque growth inhibition of a stannous fluoride dentifrice with as few as 10 subjects in a cross-over design.