Clinical trial evaluating two peroxide whitening strips used by teenagers

Double-blind clinical research was conducted to compare the clinical response of a thin, concentrated peroxide whitening strip (relative to a marketed control) among a teenage population with preceding safety and efficacy data. Informed consent and child assent was obtained from 48 teens, 13-17 years of age. After baseline measurements were taken, subjects were divded randomly into two groups, one using a thin 10% hydrogen peroxide whitening strip, the other using a 6.5% hydrogen peroxide strip with a thicker gel layer. Strip use was 30 minutes twice per day for 22 days on the maxillary arch, followed by 22 days on the mandibular arch. Efficacy was measured objectively based on L*a*b* color change from digital images taken every 11 days, where L* indicates lightness and b* indicates blue-to-yellow shade. The mean age was 15.1 (+/-1.5) years. Relative to baseline, both strip groups experienced significant (p < 0.0001) color improvement for yellowness (deltab*) and lightness/brightness (deltaL*) beginning at the first visit (Day 11). Continued use resulted in significant color improvement through Day 22. Groups did not differ significantly (p > 0.33) with respect to combined deltab* or deltaL* at end-of-treatment. Tooth sensitivity and oral irritation represented the most common adverse events. No subject discontinued early due to a treatment-related adverse event. Teenagers who used either 10% hydrogen peroxide gel or 6.5% hydrogen peroxide gel whitening strips twice a day for 44 days saw significant tooth whitening without serious adverse events.     

Placebo-controlled clinical trial evaluating a 10% hydrogen peroxide whitening strip

OBJECTIVE: A placebo-controlled clinical trial was conducted to evaluate the effectiveness and safety of a 10% hydrogen peroxide strip-based whitening system in subjects with tooth discoloration and no previous history of tooth whitening. METHODOLOGY: Informed consent was obtained, and 39 healthy adults were randomly assigned to either 10% hydrogen peroxide whitening strips (Crest Whitestrips Premium) or placebo strips with no peroxide. Strips were used unsupervised twice daily for 30 minutes over a seven-day period. At day four and day eight, tooth color (L*a*b*) was measured on the maxillary anterior teeth from standard digital images, and safety was assessed from examinations and subject reports. RESULTS: After three treatment days, the 10% hydrogen peroxide strip group had significant (p < 0.0001) color improvement from baseline, with means (SD) for deltab* and deltaL* of -1.57 (0.472) and 1.72 (0.619), respectively. Continued strip use from day four to day eight resulted in significant (p < 0.002) incremental improvement in both yellowness and lightness. By the end of treatment (day eight), the adjusted mean (SE) color change between groups was -2.20 (0.275) for deltab* and 2.24 (0.254) for deltaL*, a highly significant (p < 0.0001) color improvement for the 10% hydrogen peroxide group relative to placebo, of similar absolute magnitude for deltab* and deltaL*. Treatment with the 10% hydrogen peroxide strips was well-tolerated, with tooth sensitivity and oral irritation representing the most common findings. CONCLUSION: In this double-blind, placebo-controlled clinical trial, statistically significant tooth whitening was evident after three days' treatment with 10% hydrogen peroxide whitening strips, and color improved with continued usage over seven days.     

Clinical trial comparing 2 hydrogen peroxide tooth whitening systems: strips vs pre-rinse

A randomized, examiner-blind, parallel-group, clinical trial evaluated the efficacy and safety of a whitening, prebrushing mouthrinse compared with a whitening strip control. Both the pre-rinse (2% hydrogen peroxide) and whitening strips (10% hydrogen peroxide) were used twice daily with normal toothbrushing over a 1-week period. Clinical response (efficacy and safety) was evaluated on day 3 and day 8. Tooth color (L*a*b*) was measured objectively from standardized digital images of the maxillary anterior teeth, while safety was assessed from the clinical examination and participant report. All 28 randomized participants completed the study. Relative to baseline, the whitening strip group experienced significant (P <.001) color improvement at day 3, continuing (P <.001) through day 8. The pre-rinse group did not show any significant (P >.12) change at day 3, and had a significant (P=.033) increase in yellowness at day 8. Adjusted mean +/- standard error treatment differences were -1.75 +/- 0.198 for deltab*, 1.11 +/- 0.212 for deltaL*, and -0.54 +/- 0.131 for deltaa*, with the strip group exhibiting significantly (P <.001) greater whitening at day 8. Both products were well tolerated, with no participants discontinuing treatment early as the result of an adverse event. In head-to-head testing, 7-day use of the 10% hydrogen peroxide whitening strips resulted in significant tooth color improvement relative to a barrier-free 2% hydrogen peroxide pre-brushing mouthrinse.     

Clinical comparison of two self-directed bleaching systems

PURPOSE: This randomized clinical trial compared the clinical efficacy and tolerability of 2 marketed self-directed vital tooth-whitening systems. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.     

A randomized controlled trial of home tooth-whitening products

PURPOSE: To evaluate the effectiveness of two marketed home tooth-whitening products. METHODS: A randomized controlled clinical trial involving 87 adults who were randomly allocated into one of three groups: (1) 6% hydrogen peroxide whitening strips, (2) 18% carbamide peroxide whitening gel, and (3) a placebo (fluoride toothpaste) control group. Subjects were instructed individually and then used the given product daily for 2 consecutive weeks. Color was determined in brightness (L*), yellowness (b*) and redness (a*) [color space] at baseline and 8 weeks after dispensing the product by employing a high resolution digital camera (Fuji HC1000 CCD) to image the subject's anterior maxillary teeth under standard polarized lighting conditions. The subjects also completed a questionnaire on self-satisfaction with the treatment outcome. RESULTS: One-way ANOVA (Bonferroni test) demonstrated significant differences in color between the three groups with changes in brightness (L*, P< 0.001), yellowness (b*, P< 0.001) and redness (a*, P < 0.001). Changes in L* a* b* was greatest among those who used the 6% hydrogen peroxide whitening strips. Subjects in the whitening strip group also rated that product significantly (P < 0.01) more favorably than other groups with respect to the amount of whiteness improvement, as well as whitening satisfaction and overall impression while there is no significant difference between the whitening gel and the placebo groups.     

Clinical study to compare two in-office (chairside) whitening systems

The objective of this clinical study was to compare the whitening/bleaching efficacy of two marketed in-office whitening systems: Discus Dental Zoom! Chairside System (25% hydrogen peroxide whitening gel) and Opalescence Xtra Boost Kit (38% hydrogen peroxide whitening gel), using the Vita Shade Guide and chromameter measurements. The study was an examiner-blind, parallel group, randomized and controlled clinical trial conducted in a dental setting. All subjects signed a study consent form prior to admission and were given Crest Regular Toothpaste and an Oral-B 40 straight-handle toothbrush to use during the study. Subjects received a supragingival prophylaxis followed by a screening eligibility Vita Shade assessment from which 22 subjects were selected. At baseline, all six maxillary anterior teeth were assessed with the Vita Shade Guide. Chromameter measurements were taken on either the right maxillary central or left maxillary central (tooth No. 8 or tooth No. 9). Subjects were assigned to one of two treatment groups, and had three applications of their assigned product. Following completion of the treatment phase, and on post-treatment Days 2 and 7, a visual examination of the condition of the oral soft tissues, together with a Vita Shade assessment on maxillary anterior teeth, a chromameter reading and a questionnaire regarding tooth sensitivity were completed. At the termination of the study, the statistical analysis of the Vita Shade scores indicated that both products significantly (p < 0.0001) lightened the color of the teeth. The average improvement was between 6 and 9 shade changes. Additionally, the Zoom! Chairside System was significantly better than the Opalescense Xtra Boost Kit at all time points: post-treatment (p < 0.0001); Day 2 (p < 0.004); Day 7 (p < 0.003). This difference was between 1 and 2 shade changes. The chromameter readings showed a significant difference in the overall color change (delta E) to a lighter color for both the Zoom! Chairside System and the Opalescence Xtra Boost Kit. Using delta E, the Zoom! Chairside System was directionally better than the Opalescense Xtra Boost Kit at Day 2 (p < 0.08), and significantly better at Day 7 (p < 0.025). Analysis of the composite parameters of delta E (L*, a*, b*) showed that no differences could be detected in the a* (redness) parameter. Changes were observed in the L* (brightness) and b* (yellow) parameters which paralleled the delta E differences. There were no significant differences in induced sensitivity between whitening systems at any time point.     

Use of a physical barrier to improve efficacy of a paint-on whitening gel: a seven-day randomized clinical trial

OBJECTIVE: This randomized, examiner-blind clinical trial evaluated the impact of a physical barrier on tooth whitening response of a peroxide-containing paint-on gel. METHODOLOGY: A total of 33 adult volunteers, ranging from 18-75 years of age, were randomized to one of two treatment groups: a whitening paint-on gel used alone, or a whitening paint-on gel applied to the tooth surface and immediately covered with a polyethylene strip barrier. Both treatments were used twice a day for seven days, and all subjects used a cavity protection dentifrice and an extra-soft toothbrush twice a day while in the study. Whitening efficacy was assessed using L*a*b* color analysis obtained via digital imaging. Efficacy and safety data were collected at baseline and again at Days 2, 5, and 8. RESULTS: Use of a whitening gel with a protective barrier resulted in significant (p < or = 0.025) color improvement from baseline (as evident by mean deltab* and deltaL*) at Days 5 and 8, while changes from baseline were not significant for the group using whitening gel alone for the same time points. At Day 2, subjects in the barrier group had a significant (p = 0.046) yellowness reduction (deltab*) relative to baseline. Between-treatment comparisons were significant for deltab* at Days 5 and 8 (p < or = 0.015) and for deltab* whitening improvement slopes for the duration of the study (p < 0.002). Both treatments were well tolerated, and no subjects discontinued treatment due to an adverse event. CONCLUSION: Protecting hydrogen peroxide in the whitening gel from the oral environment with a polyethylene barrier increases the magnitude of the whitening response for a paint-on gel, with results evident as early as after five days of product use.     

CLINICAL TRIALS ON THE USE OF WHITENING STRIPS IN CHILDREN AND ADOLESCENTS

Objective : This article reported the cumulative findings from three controlled, randomized clinical trials evaluating the efficacy and tolerability of tooth whitening in children and adolescents using disposable polyethylene strip systems. Materials and Methods : The study population included 132 children and adolescents, ages 10 to 18 years. (Please note that 71 of these subjects were identified in the previous review.) Fifty‐three percent of the subjects were female and 47% were male, with a mean age of 14.4 years. Subjects were divided into experimental treatment groups by balancing groups with respect to demographic characteristics and baseline tooth colors. Subiects were treated with either 5.3% or 6.5% hydrogen peroxide gel polyethylene strips. All subjects had to have all permanent anterior teeth erupted, a baseline Vita shade (Vita Zahnfabrik, Bad Säckingen, Germany) score of A2 or darker, and a desire that their teeth be whitened. One study included subjects who had previously received comprehensive orthodontic treatment. Digital images were collected for all subjects at baseline, 2 weeks, and 4 weeks. Oral examinations and interviews were conducted at each appointment to evaluate adverse events. Color change was calculated from the digital images in the same manner previously described. Results : The 5.3% and 6.5% hydrogen peroxide strips used for 30 minutes twice a day yielded significant tooth whitening (p < .0001) after 14 days. For the primary whitening parameter, δb*, continued treatment during the 14‐ to 28‐day period resulted in significant additional reduction in yellowness (p < .0001). Subjects treated with 6.5% hydrogen peroxide strips experienced significantly (p < .03) greater reduction in yellowness (approximately 0.8 δb* units) compared with those who used the 5.3 hydrogen peroxide strips. The hydrogen peroxide strips were tolerated well in all of these studies, with minor tooth sensitivity and oral irritation being the primary complaints. Eighteen subjects (14%) reported oral irritation, whereas 30 subjects (23%) reported tooth sensitivity. All adverse events were relieved upon discontinuance of product use. Conclusion : The 5.3% and 6.5% hydrogen peroxide gel strips used for 30 minutes twice a day effectively whitened teeth, and both regimens were well tolerated.     

Randomized controlled trial of professional at-home tooth whitening in teenagers

A randomized controlled clinical trial was conducted to compare two professional at-home tooth whitening systems in a teenage population. Informed consent and child assent were obtained from 60 teenagers aged 12-17 (mean age = 14.8). After baseline measurements, subjects were randomized to one of two groups, using either 14% hydrogen peroxide whitening strips or 10% carbamide peroxide in a custom bleaching tray. Strips were used for 30 minutes twice daily, while the tray was worn overnight. Treatment took place for 14 days sequentially, first on the maxillary arch and then on the mandibular arch; all use was unsupervised. Efficacy was measured objectively by L*a*b* color change from digital images obtained at baseline and end of treatment, using combined color measures for both arches. Both professional whitening systems had significant (p < 0.0001) reductions in yellowness (Deltab*) and increased lightness (DeltaL*) after two weeks of treatment on each arch. At the end of treatment, Deltab* or DeltaL* did not differ significantly between the groups (p > 0.28). Tooth sensitivity and mild oral irritation represented the most common adverse events, with only one subject discontinuing treatment as a result. Teenagers who used either bleaching method for two weeks experienced significant tooth whitening without serious adverse events.     

Clinical response of three whitening products having different peroxide delivery: comparison of tray, paint-on gel, and dentifrice

OBJECTIVE: Comparative clinical research was conducted to evaluate the efficacy and safety of three peroxide-containing tooth whitening products having different peroxide delivery. METHODOLOGY: 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. RESULTS: 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. CONCLUSION: 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.     

Clinical response of three direct-to-consumer whitening products: strips, paint-on gel, and dentifrice

A randomized, examiner-blind, parallel-group, 3-week clinical trial evaluated the efficacy and safety of 3, popular, direct-to-consumer whitening products: a paint-on gel, a whitening dentifrice, and whitening strips. Both the paint-on gel (18% carbamide peroxide) and the whitening strips (6% hydrogen peroxide) were peroxide-based systems, while the dual-phase whitening dentifrice incorporated surface cleaning agents and sodium fluoride, but contained no peroxide. Treatment consisted of twice-daily use over 3 weeks following label instructions, except that strips were applied only during the first 14 days as per the manufacturer's instructions. Tooth color was measured on the maxillary anterior teeth from polarized digital images. Safety was assessed by examination and subject report. A total of 48 healthy adults were randomized, and 42 completed 1 or more post-baseline visits. For the primary efficacy variable delta b*, the adjusted mean +/- standard error reduction in yellowness was -0.06 +/- 0.131 for the dentifrice with no peroxide and -0.21 +/- 0.109 for the 18% carbamide peroxide paint-on gel, compared with -2.53 +/- 0.244 for the whitening strip control. Only the strip group exhibited significant (P < 0.0001) delta b* improvement. Between-group comparisons demonstrated significant and improved whitening for the strip treatment compared with the whitening dentifrice or paint-on peroxide gel, as evidenced by the more than 2-unit improvement in delta b* at week 3. Regardless of the parameter (delta b*, delta L*, delta a*, or delta E*), this represented a significant (P < 0.0001) color improvement for the whitening strips relative to both of the comparative treatments. There were no significant differences in color improvement for the 18% carbamide peroxide paint-on gel used for up to 3 weeks continuously, compared with normal brushing with a dual-phase whitening dentifrice. All products were well tolerated, with no subjects discontinuing treatment early because of adverse events. In head-to-head testing conditions, 14-day use of the 6% hydrogen peroxide whitening strips resulted in superior improvement in tooth color compared with either of the experimental controls.     

Vital bleaching with a thin peroxide gel: the safety and efficacy of a professional-strength hydrogen peroxide whitening strip

BACKGROUND: Use of higher peroxide concentrations for professional at-home vital bleaching often balances two factors in patient compliance: whitening and tolerability. Development of a polyethylene strip coated with a very thin (0.10-millimeter) layer of 14 percent hydrogen peroxide gel (Crest Whitestrips Supreme, Procter & Gamble, Cincinnati)--which represents an increase in concentration and a decrease in amount of gel--was believed to allow for greater at-home whitening with little additional oral soft-tissue exposure to peroxide. METHODS: The authors conducted a randomized, double-blind, two-week clinical trial with 38 adults to evaluate the safety and efficacy of twice-daily use of the thin, concentrated bleaching gel strip versus the effects of a control product (Crest Whitestrips, Procter & Gamble). The two products differed only in concentration (14 percent versus 6 percent) and gel layer thickness (0.10 mm versus 0.20 mm). The authors measured efficacy from digital images using the Commission Internationale de l'Eclairage L*a*b* color scale. They assessed safety via subject interviews and clinical examination and compared treatments using analysis of covariance. RESULTS: Relative to baseline color, both strip groups exhibited significant (P < .001) improvement in yellowness, brightness and composite color change. Between-group comparisons after two weeks demonstrated significant (P < .003) color improvement for the experimental strip relative to the control. Both products were well-tolerated generally. Despite the concentration differences, clinical examination of each group showed a similar low level (11 percent) of "minor oral irritation." CONCLUSION: Use of the thin 14 percent hydrogen peroxide gel strip resulted in greater whitening, including 42 to 49 percent greater improvement in tooth color and faster whitening onset than that seen with a 6 percent hydrogen peroxide whitening strip, without clinical evidence of increased oral-tissue irritation. CLINICAL IMPLICATIONS: Use of whitening strips with a thin, concentrated layer of hydrogen peroxide gel may represent a useful approach for professionally directed at-home vital bleaching.     

Randomized clinical trial on the efficacy of 2 over-the-counter whitening systems.

OBJECTIVE: The purpose of this clinical trial was to evaluate the efficacy of 2 over-the-counter whitening systems: a liquid whitening gel (5.9% hydrogen peroxide, twice a day for 15 minutes), and a sodium chlorite-based whitening gel applied in a tray system (10 minutes twice a day). METHOD AND MATERIALS: Sixty volunteers (minimum shade A3 on 1 maxillary tooth) were selected to participate in this single-blind (examiner-blinded), single-center, 2-group trial. The subjects were randomly divided into 2 groups (n = 30 each) and instructed to bleach their teeth for 2 weeks. Efficacy was measured using the Vita Classical shade guide and a spectrophotometer at baseline, as well as after 2 weeks and 6 months. RESULTS: For the subjectively measured tooth shades, improvement for maxillary canines was 2.03 +/- 3.67 tooth shades in group 1 and 1.08 +/- 2.19 tooth shades in group 2 after 2 weeks; the maxillary incisors revealed a tooth shade improvement of 0.83 +/- 1.71 tabs in group 1 and 0.73 +/- 2.22 tabs in group 2 (P < .05, except maxillary incisors in group 2; t test). Objectively measured tooth shade scores revealed a change of 0 +/- 0.25 tooth shade tabs (P > .05). CONCLUSIONS: The bleaching gel containing hydrogen peroxide achieved a slight improvement, and the sodium chlorite-based bleaching gel achieved only a small tooth color improvement. Moreover, subjectively and objectively measured tooth shades revealed considerably different results in the clinical situation.     

Dental effects of home bleaching gels and whitening strips on the surface hardness of resin composites

PURPOSE: To evaluate the effects of two bleaching gels and two whitening strips on surface hardness of four resin composites in vitro. METHODS: 60 cylindrical samples of each composite (Surefil, Charisma, Admira, Flowline) were prepared (4 mm thickness and 6 mm diameter) and stored in distilled water at 37 degrees C for 24 hours. These samples were randomly divided into six test groups (n=10). One group was selected for baseline and Vickers microhardness measurements (load= 100 g, dwell time 20 seconds) were taken immediately. The other groups were treated for 21 days with one of the following: distilled water (control), containing 10% carbamide peroxide bleaching gel (Perfect Bleach), 16% carbamide peroxide bleaching gel (Viva Style), 5.3% hydrogen peroxide whitening strips (Crest Whitestrips) and 14% hydrogen peroxide whitening strips (Crest Whitestrips Supreme). The treated samples were also subsequently subjected to the same microhardness testing by using the same method as applied to the baseline measurements. Data were analyzed statistically (alpha = 0.05). RESULTS: Overall, the lowest surface hardness value was observed in baseline measurements. An increase in surface hardness was noted in all of the other groups. The higher surface hardness values were found in control, whitening strip (5.3% HP) and bleaching gel (10% CP) groups than whitening strip (14% HP) group. Bleaching gel (16% CP) was statistically different from only baseline measurements. In addition, regardless of the tested groups, statistically significant differences in surface hardness were observed between composite materials. Surefil showed the highest hardness values while Flowline presented the lowest hardness values.     

Randomized controlled trial of 10% hydrogen peroxide whitening strips

OBJECTIVE: This research compared the clinical response of two different peroxide-containing gel formulations delivered using self-applied whitening strips. METHODOLOGY: A randomized, double-blind clinical trial was conducted to compare a one-week 10% hydrogen peroxide thin (0.13 mm) bleaching gel (Crest Whitestrips Premium) to a marketed two-week 6% hydrogen peroxide strip (0.20 mm) control (Crest Whitestrips). The maxillary arch was treated twice daily for 30 minutes. Efficacy (L*a*b* color change) was measured objectively by digital image analysis after one and two weeks. RESULTS: A total of 40 adults ranging from 19-48 years of age participated in the study. Both treatments were effective in whitening teeth, as evidenced by a statistically significant improvement from baseline (p < 0.001) beginning at one week. At that time, the adjusted mean deltab* (SE) (yellowness reduction) for the 10% strip was -2.42 (0.147) compared to -1.91 (0.143) for the 6% strip, with the treatments differing significantly (p = 0.02). At two weeks, the adjusted mean deltab* (SE) for the 10% strip was -3.31 (0.182) compared to -2.49 (0.167) for the control. After two weeks, treatments differed significantly (p < 0.02) for deltab* and deltaL* (lightness improvement). Comparing results from two weeks of the 6% control strip to one week of the 10% strip, the mean deltab* treatment difference was -0.07 (90% confidence interval from -0.44 to +0.31). Both treatments were generally well tolerated, with mild and transient tooth sensitivity or oral irritation representing the most common adverse events. CONCLUSION: Vital bleaching with 10% hydrogen peroxide strips at one week was as effective as 6% hydrogen peroxide strips used for two weeks.     

TOOTH WHITENING IN CHILDREN

Objective : This clinical study evaluated the efficacy and tolerability of tooth whitening in children and adolescents, using a marketed, tray‐ based tooth‐whitening system and a disposable polyethylene strip system. Materials and Methods : A study population of 106 children and adolescents, ages 11 to 18 years, participated in this study. There were 61 girls and 45 boys, with a mean age of 14.7 years. Subjects were divided into two experimental treatment groups, the groups being balanced with respect to demographic characteristics and baseline tooth color. All subjects had to have all permanent anterior teeth erupted, a baseline Vita shade (Vita Zahnfabrik, Bad Säckingen, Germany) score of A2 or darker, and the desire to whiten their teeth. One experimental group included 71 subjects who used a 6.5% hydrogen peroxide strip system (Crest Whitestrips Professional Strength, Procter & Gamble, Mason, OH, USA) for 30 minutes twice daily. The other experimental group included 35 subjects who used a 10% carbamide peroxide tray system (Opalescence, Ultradent Products, South Jordan, UT, USA) overnight. Subjects who had previously vital bleached their teeth, exhibited apparent caries or periodontal problems, had orthodontic appliances or anterior restorations, or reported dentin hypersensitivity were excluded. The study population was treated in two separate cohorts, by two independent investigations, to minimize the effects of examiner bias. Digital images were collected for all subjects at baseline, 2 weeks, and 4 weeks, with the maxillary and mandibular arches being treated separately for 4‐week intervals. An oral examination was conducted at baseline and at all recall intervals. Subjects reported any adverse events in interviews. Color change was calculated from digital images where L* indicated lightness, a* redness, and b* yellowness. Comparisons between the two experimental groups were made using a two‐sided analysis of covariance with a 5% significance level. Results : Both experimental systems exhibited significant (p < .001) tooth‐whitening improvement relative to the baseline. Color change was greater in the maxillary teeth than in the mandibular teeth for both systems evaluated. The color change for maxillary teeth was not significantly different between the two systems evaluated; however, the tray system demonstrated significantly (p < .05) greater toothwhitening effectiveness for the mandibular teeth. Both treatment regimens were well tolerated. Minor tooth sensitivity and oral irritation were the most commonly reported adverse events, being reported by 49% of the subjects assigned to the strip group and 43% of the subjects in the tray group. All reported that adverse events were relieved immediately upon discontinuance of product use. Conclusion : The 6.5% hydrogen peroxide gel strips and the 10% carbamide peroxide gel delivered overnight in customized trays effectively whitened teeth, and both treatment regimens were well tolerated.     

Comparison of clinical efficacy and safety of three professional at-home tooth whitening systems

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.     

Comparison of two at-home whitening products of similar peroxide concentration and different delivery methods

PURPOSE : This study compared the whitening efficacy, side effects, and patients' preferences/perceptions of two whitening systems of similar peroxide concentration but different formulation and delivery methods. METHODS : The tooth color change of 24 participants was measured using a shade guide (BSG) and a spectrophotometer (ES). Color difference was calculated: ΔE* = [(ΔL*)(2) + (Δa*)(2) + (Δb*)(2)](1/2). One whitening treatment was randomly applied to the right or left maxillary anterior teeth and the other was applied to the contralateral teeth, at-home with 35% carbamide peroxide in a tray (TW) or with 14% hydrogen peroxide in strips (WS). The tooth color was evaluated at baseline, 15 and 30 days (15 days postwhitening). Participants rated their tooth and soft tissue sensitivity (1-10 scale) and completed a questionnaire on their preferences. Results were analyzed by repeated measurement regression analysis/Tukey and Mann-Whitney (p<0.05). RESULTS : At 15 days, the teeth treated with TW and WS presented ΔE* = 7 and 6, respectively (ΔBSG=3 for both), and at 30 days, they presented ΔE* = 7.5 and 6.5, respectively (ΔBSG=3 for both). There was no significant difference in tooth and soft tissue sensitivity between treatments. No participant reported tooth and gingival sensitivity at the postwhitening appointment. Of the participants, 83% preferred the TW over WS. CONCLUSION : Both ΔE* and ΔBSG showed no significant difference in tooth color change between TW and SW at either time point. By the end of the study no participants reported tooth and gingival sensitivity. Participants preferred TW over SW.     

Effectiveness and safety of tooth bleaching in teenagers

PURPOSE: The purpose of this study was to compare the efficacy and safety outcomes of a currently marketed, peroxide-containing, tray-based, tooth-whitening system to a peroxide-containing, "trayless" tooth-whitening system. METHODS: Fifty-seven subjects, 12 to 17 years of age, participated in this study and were divided into 2 balanced groups. Twelve subjects received custom trays with 10% carbamide peroxide gel that they were instructed to wear overnight. Forty-five subjects received 10% hydrogen peroxide polyethylene strips to wear for 30 minutes twice a day. Teeth were bleached for 2 weeks. Digital image analysis measured color in B, L, and A color spaces, where B indicated yellowness, L indicated lightness, and A indicated redness. Oral examinations and interviews were used to ascertain any adverse events that may have occurred during treatment. RESULTS: Fifty-one patients completed this study. Both whitening systems yielded significant (P<.001) color improvement, as evidenced by decreased yellowness, increased lightness, and decreased redness. Groups did not differ significantly (P>.39) regarding color improvement for B, L, or A on either the maxillary or mandibular teeth. Twelve subjects (27%) in the polyethylene strip group reported adverse events compared to 5 subjects (42%) in the tray-delivered group. Minor and transient tooth sensitivity and oral irritation were the most common adverse events. CONCLUSIONS: Both the daytime strip and overnight tray groups significantly (P<.0001) whitened teeth; there were no significant differences between the 2 groups in any of the color parameters; both whitening systems were well tolerated, and most adverse events were mild in severity.     

Patients’ Assessments of Tooth Sensitivity Increase One Day Following Different Whitening Treatments

ObjectivesThe aim of this clinical study was to compare tooth sensitivity scores and color change values before and 1 day following whitening treatments using different concentrations of whitening agents for in-office and at-home procedures.Materials and methodsA total of 60 participants divided into 3 groups were included in this study. A whitening procedure was carried out in groups using 40% hydrogen peroxide (HP) in in-office treatment, 16% and 10% carbamide peroxide (CP), respectively. Participants rated their tooth sensitivity at the baseline and 1 day following the treatment. The CIEl_ab values were recorded and color differences were calculated.ResultsWithin each of the whitening treatments, the tooth sensitivity scores significantly increased following the procedure (p<0.05). The largest significant increase in scores was noted in 40% HP in-office whitening treatment, while the lowest increase was noted in 10% CP at-home whitening treatments (p<0.05). The highest color change 1 day following the procedure was found in the 40% HP in-office whitening treatment group (3.3) and it significantly differed from both 16% CP and 10% CP at-home whitening treatments whose color difference was both 2.0, respectively (p<0.05).Conclusion1 day following the procedure, a low concentrate CP agent for at-home whitening causes the least tooth sensitivity compared to higher concentrate CP for at-home and HP for in-office agents, with the same color change efficacy as higher concentrate CP agent. In case with slight tooth sensitivity reported at the baseline, a 10% CP whitening treatment should be recommended.