PURPOSE To directly compare tooth color change and spatial uniformity of two brush-applied, peroxide-based overnight tooth whiteners in a 2-week randomized clinical trial. METHODS 57 adult volunteers were randomly assigned to Crest Night Effects, a 19% sodium percarbonate system packaged in unit dose sachets that when applied, dries to form an adherent film, or Colgate Simply White Night, a paint-on liquid in an applicator bottle at a concentration of 8.7% hydrogen peroxide. Both groups applied their assigned gel on the facial surfaces of the six maxillary anterior teeth for 14 nights. Efficacy was measured objectively as change in L*a*b* tooth color from standard digital images of maxillary teeth, while safety was evaluated by clinical examination and interview. RESULTS After 14 nights treatment, adjusted mean (SE) change in yellowness (delta b*) was -0.95 (0.092) for the 19% sodium percarbonate film and -0.17 (0.096) for the 8.7% hydrogen peroxide gel, with these groups differing statistically (P < 0.0001). Other individual and composite color parameters also demonstrated significantly greater whitening for the 19% sodium percarbonate film compared to the 8.7% hydrogen peroxide gel after 14 nights use. Only the 19% sodium percarbonate film exhibited significant (P< 0.0001) proximal color improvement (delta b*) after 2 weeks, approximately 98% of that seen on the body of the tooth, providing evidence of proximal bleaching and uniform spatial whitening following use of this barrier-free system. Both products were well-tolerated, with no subjects discontinuing treatment early due to a causal adverse event.
Changing and whitening tooth color in people with long-standing tooth stain without excessive hard tissue abrasion may represent one of the more difficult challenges for whitening dentifrices. An eight-week clinical trial was conducted to evaluate change in tooth color by a silica-based, enamel-safe tartar control whitening dentifrice compared to a marketed baking soda dentifrice control. First, a screening exercise was conducted to identify individuals with long-standing extrinsic dental stain. This exercise targeted adults who reported "stained teeth" and coffee/tea drinking or smoking, but who had no recent history of dental prophylaxis. Targeted subjects were examined for stain (Lobene Index) and tooth shade/color (Vita). A total of 291 adults having extrinsic stain and discolored teeth were enrolled in the study. Subjects were randomized to one of the two treatment groups, and all dentifrice use was unsupervised. Tooth color was measured at 4 and 8 weeks from shade values collected from the 8 incisors, and averages were determined from a linear ordering of the shade guide. A total of 278 evaluable subjects completed the 8-week study. Overall, the tartar control whitening dentifrice group experienced an improvement in color, differing statistically from baseline (p < 0.001) and from the marketed control (p < 0.05). Safety profiles for the two dentifrices were generally similar. Among patients with long-standing extrinsic stain, use of the tartar control whitening dentifrice resulted in superior overall tooth shade and reduced maximum or worst color compared to the marketed baking soda dentifrice control.
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.