Clinical evaluation of a new 10% carbamide peroxide tooth-whitening agent. Clinical response of three whitening products having different peroxide delivery: comparison of tray, paint-on gel, and dentifrice. Comparative tooth whitening efficacy of 18% carbamide peroxide liquid whitening gel using three different regimens. Clinical comparison of two self-directed bleaching systems. Comparative clinical investigation of the tooth whitening efficacy of two tooth whitening gels. Efficacy of a novel, nontray, paint-on 18% carbamide peroxide whitening gel. Comparison of clinical efficacy and safety of three professional at-home tooth whitening systems. 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 six-month study of two self-applied tooth whitening products containing carbamide peroxide.
NUPRO Gold Tooth Whitening System was evaluated for efficacy according to the proposed ADA guidelines for acceptance. Sixty participants with discolored anterior teeth participated in a 14-day, double-blind, clinical trial. The participants were matched for age, gender, and oral health status and were given either a placebo gel without the active agent or the NUPRO Gold active gel, which they wore in a custom-fabricated mouth guard for home use. The shade of each participant's maxillary anterior teeth was evaluated using a value-oriented Vita Lumin Vacuum Shade Guide before the study. The same shade guide was used to determine shade changes. Time of use of the agent and potential side effects, such as tooth and gingival hypersensitivity and tissue irritation, were assessed at all recall examinations and were recorded by participants in daily diaries. The average shade change for the placebo users was less than one shade. The average shade change for the NUPRO Gold users was 6.96 shades. Tooth hypersensitivity varied from none to severe. Tissue irritation was minimal. The results of these evaluations indicate that NUPRO Gold is effective as a tooth-whitening system, when administered properly under the supervision of a dentist, with commonly reported side effects of transient tooth sensitivity and minimal gingival sensitivity. Little or no change in tissue health was noted. This study was supported by Dentsply Preventive Care (York, Pennsylvania). Comparative clinical research was conducted to evaluate the efficacy and safety of three peroxide-containing tooth whitening products having different peroxide delivery.
                A total of 43 healthy adults who met entrance criteria were randomly assigned to either a dual-phase, anticavity, 1% hydrogen peroxide dentifrice with a manganese gluconate activator, an 18% carbamide peroxide paint-on gel, or a 5% carbamide peroxide professional custom tray system. Following manufacturer's instructions, the activated dentifrice was used at least twice daily for two minutes, while the paint-on gel was applied twice daily. The custom tray, a barrier system and the experimental control for this study, was worn continuously for six to eight hours daily. Tooth color (L*a*b*) was measured on the maxillary anterior teeth from standard digital images, while safety was assessed from examination and subject report.
                At Day 15, the custom tray group had a significant (p < 0.002) reduction in yellowness and increased lightness, with adjusted mean (SE) deltab* of -1.83 (0.210) and deltaL* of 1.45 (0.292). The custom tray group experienced on average greater color improvement compared to either the paint-on gel or activated peroxide whitening dentifrice, differing significantly (p < 0.01) from either of the barrier-free systems with respect to deltab*, deltaL*, deltaE*, and deltaW*. In comparison, 14-days' use of the paint-on gel and activated dentifrice did not result in significant (p > 0.10) color improvements from baseline for deltab*, deltaL*, or deltaW*, with these two barrier-free systems not differing significantly (p > 0.26) with respect to any individual or composite color parameters. Tooth sensitivity and oral irritation were the most common safety findings in the tray and dentifrice groups (there were no adverse events in the paint-on group), and no subject discontinued treatment early because of a treatment-related adverse event.
                In head-to-head 14-day testing, a low concentration (5% carbamide peroxide) barrier-based tray system yielded superior tooth color improvement compared to two barrier-free delivery systems-an 18% carbamide peroxide paint-on gel and a 1% hydrogen peroxide dentifrice with a metal activator. Recently, a novel paint-on liquid whitening gel--Colgate Simply White Clear Whitening Gel--which contains 18% carbamide peroxide, has been developed as a self-administered tooth bleaching system. The purpose of the present study was to determine the efficacy and safety of this product using alternate exaggerated or simplified treatment regimens.
                This was a three-week clinical trial using a parallel, double-blind, stratified protocol with three different instructions for application: 1) twice-daily, no air-drying, and 15 minutes without eating/drinking; 2) three times daily, 30-second air-drying and 30 minutes without eating/drinking; or 3) four times daily, 30-second air-drying and 30 minutes without eating/drinking. One-hundred and twenty (120) healthy volunteers were balanced into three equal groups based on shade scores (A3 or darker). Clinical evaluations (shade guide, oral tissue health, gingival index and visual analog sensitivity score) were performed on each group at baseline and weekly for the next 21 days. At the conclusion of the study, a survey of the subjects' opinions on their assigned product regimen was also conducted.
                Subjects who used Colgate Simply White Clear Whitening Gel three and four times daily achieved the greatest shade improvement (5.88 +/- 1.53 shades, and 5.57 +/- 1.54, respectively). However, these values were only about one shade better than the value observed for the more convenient, twice-daily, "no-dry" regimen (4.51 +/- 1.77 shades), though they were statistically significant (p < 0.05). The result for the four-times daily protocol was not statistically different from the three-times group. Also, no differences were observed between the groups concerning oral tissue health, gingival index or tooth sensitivity, and no adverse effects were observed or reported regardless of the regimen used. Surveys completed by the subjects showed that those who used the twice-daily, "no-dry" regimen found the product to be the easiest to use, the most comfortable and the most pleasant tasting.
                It can be concluded from the clinical data that three or four applications of Colgate Simply White Clear Whitening Gel per day provided better efficacy. In addition, the use of the whitening gel twice daily, even without "dry time" and only 15 minutes without eating/drinking, yielded results that were comparable to previously reported results using the original on-label directions. The potential additional benefit to the "simplified regimen" is that it was perceived to be the most convenient and comfortable. The use of Colgate Simply White Clear Whitening Gel up to four times daily for up to three weeks is also safe, and the tendency of abusing the product with more frequent daily use may be deterred by the inconvenience reported by the study subjects. This randomized clinical trial compared the clinical efficacy and tolerability of 2 marketed self-directed vital tooth-whitening systems.
                Balancing for baseline tooth color, self-reported coffee/tea use, and age, 57 adult volunteers were randomized to either a whitening strip containing 6% hydrogen peroxide or a tray-based 10% carbamide peroxide/dentifrice/mouth rinse combination system. Following the manufacturer's directions, the strip group bleached twice daily for 30 minutes, whereas the tray group bleached twice daily for 20-30 minutes, preceded by tooth brushing with a whitening dentifrice and followed by mouth rinsing with a whitening solution. Treatment extended for 14 days, with evaluation at day 7 and again at day 14. Whitening response was measured objectively as L*a*b* from standardized digital images of maxillary anterior teeth. Tolerability was assessed by oral examination and subject interview. Efficacy comparisons were made using analysis of covariance, whereas tolerability was compared using the nonparametric Wilcoxon rank-sum test.
                Both treatments resulted in statistically significant (P < 0.01) improvements from baseline for all color parameters. For between-group comparisons, the 6% hydrogen peroxide strips yielded a nearly 3-fold reduction in yellowness (deltab*), a nearly 2-fold improvement in lightness (deltaL*), 2.6 times greater redness reduction (deltaa*), and a more than 2-fold change in overall color (deltaE*) compared to the tray-based combination system. Between-group comparisons were statistically significant for the all color parameters at both the day 7 and day 14 evaluations (P < 0.001). In general, 7-day use of the whitening strips provided significantly greater color improvement relative to the combination dentifrice/gel/rinse system at day 14. In addition, the groups differed significantly (P < 0.05) in bleaching tolerability severity-days, with the strip system demonstrating better overall tolerability compared to the combination system.
                The single-step 6% hydrogen peroxide strips demonstrated better overall clinical response, in terms of both tooth-whitening efficacy and tolerability, than the multiple-step tray-based combination system. The objective of this randomized, double-blind, parallel-group clinical study was to compare the tooth whitening efficacy of two tooth whitening gel products--Colgate Simply White Night Clear Whitening Gel containing either 25% carbamide peroxide, or 8.7% hydrogen peroxide--when used once daily at night.
                Following a baseline tooth shade evaluation using the Vita Shade Guide, qualifying adult male and female subjects from the Central New Jersey area were randomized into two treatment groups, which were balanced for baseline Vita Shade Guide scores, gender and age. The treatment groups were: 1) a tooth whitening gel containing 25% carbamide peroxide; or 2) a tooth whitening gel containing 8.7% hydrogen peroxide. All subjects were given a commercially available, non-whitening dentifrice and a soft-bristled toothbrush at the beginning of the study. In addition, they were also given one of the two tooth whitening gel products. All subjects were instructed to brush their teeth for one minute twice daily (morning and evening) with the non-whitening toothpaste. The subjects were further instructed to apply their assigned tooth whitening gel product once daily at night, per the instructions provided. Evaluations of tooth shade for each subject were repeated after two weeks, and again after three weeks of product use.
                Fifty-nine (59) subjects complied with the protocol and completed the three-week study. At both the two-week and three-week examinations, all subjects exhibited statistically significant (p < 0.05) tooth shade lightening relative to baseline tooth shade. Further, there was no statistically significant difference in tooth shade lightening between the two tooth whitening gel products.
                The results of this clinical study indicate that after once daily use at night for two or three weeks, a tooth whitening gel containing 25% carbamide peroxide and a tooth whitening gel containing 8.7% hydrogen peroxide both provided statistically significant tooth shade lightening relative to baseline tooth shade. The results also showed that there was no statistical difference in tooth whitening efficacy between the two tooth whitening gel products. A double-blind, 3-week, randomized, placebo-controlled, parallel-group clinical trial was conducted to evaluate the tooth-whitening efficacy of a novel nontray, "paint-on" liquid whitening gel containing 18% carbamide peroxide (Colgate Simply White Clear Whitening Gel). Efficacy was based on measured Vita tooth-shade scores collected at baseline and after 2 and 3 weeks of product use. Eighty healthy volunteers were balanced into 2 groups based on gender, age, and shade scores (A3 or higher). The duration of product usage was 30 minutes, twice daily, for 3 weeks. Results from this clinical study showed that subjects' teeth in the liquid whitening gel-treated group exhibited an overall mean 3.84-shade improvement and a 3.5-shade difference compared with teeth in the placebo gel group (statistically significant, P < .05) after 3 weeks. Furthermore, this improvement exceeds the minimum requirement to claim "clinical efficacy" as established by the "Guidelines for the Acceptance of Peroxide-Containing Oral Hygiene Products," published by the American Dental Association in 1994. Therefore, it can be concluded that Colgate Simply White Clear Whitening Gel significantly whitens teeth. A three-cell, randomized, parallel, investigator-blinded clinical trial was conducted to compare the efficacy and safety of three professional at-home tooth whitening systems, including Crest Professional Whitestrips (6.5% H2O2), Day White 2 (7.5% H2O2) and Nite White Excel 2 (16% carbamide peroxide equivalent). Ninety subjects were randomly assigned to three groups (30/group). Subjects were instructed to use the assigned whitener following the manufacturers' instructions. Clinical examinations at baseline, and on days 3, 7, 14, and 18 (Day White), or 21 (Crest Professional Whitestrips and Nite White) included the following parameters: 1) oral tissues; 2) tooth shade by the Vitapan Classical shade guide; 3) tooth shade by a chromameter with a jig; and, 4) tooth sensitivity and gingival irritation. The results showed significant shade reductions with time in all three groups. Nite White resulted in significantly greater shade reductions in periods between days 7, 14, or 21 and baseline than did the other two systems. Tooth sensitivity and gingival irritation, which were mostly mild and transient, occurred in all groups. It is concluded that all three whitening systems evaluated are effective and safe. Nite White Excel is superior to the other two systems because it provides a greater whitening efficacy with comparable or lower incidence of tooth sensitivity and gingival irritation. 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. Bleaching offers a non-interventive way of improving the appearance of sound, yet discolored anterior teeth. Until recently, the whitening agent was applied using a tray, but now other methods of delivering whitening agents, such as those using brush applicators, are available. This study investigated the tooth whitening efficacy of two novel, self-applied tooth whitening systems containing either 18% (Group 1) or 16.4% (Group 2) carbamide peroxide. Ninety-five subjects, ranging in age from 18 to 70 with anterior teeth A3 or darker, were recruited and randomly allocated to a group. The subjects were instructed to apply the formulation to all maxillary anterior teeth after brushing in the morning and evening. At baseline, two weeks and six months the upper six anterior teeth of the subjects were measured using the Vita shade guide tab system. In addition, the gingival health of the labial surfaces of the upper six anterior teeth was assessed using the Loee and Silness Gingival index (Loee & Silness, 1963) at baseline and at two weeks. The mean (SD) reduction in shade guide scores was 4.1 (2.4) shade guide tabs for subjects in Group 1, compared to 3.7 (2.6) shades for those in Group 2. This difference was not statistically significant (p=0.5). During the course of study, the gingivitis scores reduced from a mean (SD) of 0.91 (0.62) at baseline to 0.44 (0.55) at final examination (48% reduction). At the six-month recall, the mean (SD) reduction in shade guide scores was 2.3 (2.7) shade guide tabs for subjects in Group 1, compared to 2.5 (2.5) shades for those in Group 2. The different concentrations tested were found to be equally effective in improving the whiteness of upper anterior teeth by approximately four shades over a two-week period and the majority of the whitening benefit (c.60%) was sustained at six-month recall.
There is evidence that whitening products work when compared with placebo/no treatment. There are differences in efficacy between the products, mainly due to the levels of active ingredients, hydrogen peroxide and carbamide peroxide. All trials were however short term and the majority of the studies were judged to be at high risk of bias and were either sponsored or conducted by the manufacturers. There is a need for pragmatic long-term and independent clinical studies that include participants representing diverse populations. There is also a need to evaluate long-term harms. Several studies reported (where measured) the common side effects of tooth sensitivity and gingival irritation, and people should be informed of this.