Robert W. Gerlach

Perioperative use of 0.12% chlorhexidine gluconate for the prevention of alveolar osteitis: Efficacy and risk factor analysis

OBJECTIVES The purposes of this study were to evaluate the use of 0.12% chlorhexidine gluconate as a prophylactic therapy for the prevention of alveolar osteitis and to further examine subject-based risk factors associated with alveolar osteitis. STUDY DESIGN The trial was a randomized, double-blind, placebo-controlled, parallel-group study conducted among 279 subjects, each of whom required oral surgery for the removal of a minimum of one impacted mandibular third molar. Subjects were instructed to rinse twice daily with 15 ml of chlorhexidine or placebo mouthrinse for 30 seconds for 1 week before and 1 week after the surgical extractions. This regimen included a supervised presurgical rinse. Alveolar osteitis diagnosis was based on the subjective finding of increasing postoperative pain at the surgical site that was not relieved with mild analgesics, supported by clinical evidence of one or more of the following: loss of blood clot, necrosis of blood clot, and exposed alveolar bone. RESULTS In comparison with use of the placebo mouthrinse, prophylactic use of the chlorhexidine mouthrinse resulted in statistically significant (p < 0.05) reductions in the incidence of alveolar osteitis. With chlorhexidine therapy, the subject- and extraction-based incidences of alveolar osteitis in the evaluable subset (271 subjects) were reduced, relative to placebo, by 38% and 44%, respectively. The corresponding odds ratios that describe the increased odds of experiencing alveolar osteitis in the placebo group were 1.87 and 2.05 for subject- and extraction-based analyses, respectively. In comparison with nonuse of oral contraceptives, the use of oral contraceptives in female subjects was related to a statistically significant increase in the incidence of alveolar osteitis (odds ratio = 1.92, p = 0.035). Relative to male subjects, the observed incidence of alveolar osteitis for female subjects not using oral contraceptives was not statistically significant (odds ratio = 1.18, p = 0.64). Smoking did not increase the incidence of alveolar osteitis relative to not smoking (odds ratio = 1.20, p = 0.33). CONCLUSIONS These data confirm that the prophylactic use of 0.12% chlorhexidine gluconate mouthrinse results in a significant reduction in the incidence of alveolar osteitis after the extraction of impacted mandibular third molars. In addition, oral contraceptive use in females was confirmed to be a risk factor for the development of alveolar osteitis.

Oral malodor reduction by a combination of chemotherapeutical and mechanical treatments

Bacterial proliferation and plaque accumulation on the surface of the tongue are major factors contributing to oral malodor. In this research, we used subjective and objective methods to evaluate the breath benefit of a triclosan-containing dentifrice (Blend-a-Med Complete Night) with and without tongue brushing in a randomized, examiner-blinded, three-period crossover clinical trial. Twenty-nine adults (mean age 40.2 years) with morning malodor were randomly assigned to a treatment sequence: triclosan dentifrice, triclosan dentifrice plus tongue brushing, and a control dentifrice (Crest Cavity Protection). The subjects used each product four times in 27 h with a 2-day wash-out period between treatments. Halimeter measurements were taken at baseline and at 3, 24 and 27 h. Subject questionnaire data assessing the breath quality were collected at 24 and 27 h. Both triclosan regimens showed significant improvement in oral malodor (p<0.03) relative to the control. Significant (p=0.035) malodor benefit was observed when tooth brushing with triclosan dentifrice was supplemented with tongue brushing. The triclosan dentifrice was associated with significant improvement (p<0.05) in morning mouth feel and feeling of clean and fresh breath during the day relative to the control. There were no adverse events reported. The triclosan dentifrice was effective against overnight and daytime oral malodor. Supplementing routine brushing with tongue brushing resulted in additional breath improvement and breath benefits of the triclosan dentifrice were first-person noticeable.

Clinical Trial Assessing Light Enhancement of In-office Tooth Whitening

OBJECTIVE Evaluate a light-enhanced in-office tooth whitening system in order to assess tooth color and safety. METHODS Thirty-three adults were randomly assigned to one of three treatment groups. Professional treatment involved application of a 25% H(2)O(2) gel (Discus Dental ZOOM!) with light enhancement, H(2)O(2) gel alone, or the light alone with no peroxide. The 12 anterior teeth were treated three times for 20 minutes each. Efficacy was measured objectively as L*a*b* color change using digital images, tooth shade was measured, and safety was evaluated immediately after treatment and at posttreatment days 7 and 30. RESULTS After adjusting for baseline and age, immediate (end-of-treatment) means (SE) for Deltab* (yellowness) were -3.1 (0.25) for the gel + light, -2.0 (0.25) for the gel-only group, and -2.4 (0.25) for the light-only group. Significant (p < 0.05) color rebound was evident at posttreatment day 7. By day 30, adjusted means (SE)for Deltab* were -1.7 (0.20) for the gel + light group, -1.1 (0.20) for the gel-only group, and -0.5 (0.20) for the light-only group. Both peroxide groups differed significantly (p < 0.05) from light alone on Deltab* and DeltaL*. In the gel + light group, 91% of subjects experienced tooth sensitivity, the majority of which was moderate or severe. Adverse events were low in the light-only group. CONCLUSION Use of light enhancement for in-office whitening leads to immediate color change, after which there was significant color and shade rebound within 7 days as well as moderate-to-severe tooth sensitivity during and after treatment. CLINICAL SIGNIFICANCE Increased tooth sensitivity during treatment and appreciable short-term color rebound after treatment may impact the utility of in-office tooth whitening with peroxide and light as a stand-alone esthetic procedure. (J Esthet Restor Dent 21:336-347, 2009).

Relative anti‐caries efficacy of 1100, 1700, 2200, and 2800 ppm fluoride ion in a sodium fluoride dentifrice over 1 year

There is limited evidence from clinical trials on the dose response of sodium fluoride dentifrices at concentrations above 1100 ppm fluoride ion, with respect to caries efficacy. This randomized, double-blind study examined the anti-caries effectiveness of sodium fluoride dentifrices containing 1700 ppm, 2200 ppm and 2800 ppm fluoride ion relative to an 1100 ppm fluoride ion control. A population of 5439 elementary schoolchildren, aged 6-15 years, was recruited from an urban central Ohio area with a low fluoride content water supply (<0.3 ppm). Subjects were examined by visual-tactile and radiographic examination at baseline and after 1, 2, and 3 years of using the sodium fluoride dentifrices. Subjects were stratified according to gender, age and baseline DMFS scores derived from the visual-tactile baseline examination and randomly assigned to one of four treatment groups: 0.243% sodium fluoride (1100 ppm fluoride ion), 0.376% sodium fluoride (1700 ppm fluoride ion), 0.486% sodium fluoride (2200 ppm fluoride ion), and 0.619% sodium fluoride (2800 ppm fluoride ion). All products were formulated with the same fluoride compatible silica abrasive. Results after 1 year provided evidence of a positive sodium fluoride dose response. Compared to the 1100 ppm fluoride treatment group, the 1700 ppm fluoride treatment group had an 11.0% reduction in DMFS that was not statistically significant, while the 2200 ppm and 2800 ppm fluoride treatment groups showed statistically significant (P<0.05) reductions of 18.6% and 20.4%, respectively. The reductions in caries delivered by the higher fluoride dentifrices were present across all tooth surface types, but were most pronounced for occlusal surfaces. Results at years 2 and 3 were confounded by a concurrent fluoride rinse program, which involved portions of the study population. While the trends for the higher fluoride dentifrices observed at year 1 remained at years 2 and 3, the difference observed between treatments were substantially less and failed to reach statistical significance (P<0.05). Collectively, the data demonstrate that the 2200 ppm and the 2800 ppm fluoride treatments delivered statistically significantly greater caries efficacy than the 1100 ppm fluoride treatment. This large-scale clinical trial provides evidence of a positive statistically significant dose relationship between dental caries and sodium fluoride in a dentifrice at levels above 1100 ppm fluoride at year 1.

Single site meta-analysis of 6% hydrogen peroxide whitening strip effectiveness and safety over 2 weeks

OBJECTIVES This research evaluated efficacy and safety of 6% hydrogen peroxide whitening strips from a clinical trials database accumulated over a multi-year period at a single site. METHODS The inclusive meta-analysis involved seven different randomized clinical trials at one dental school. Each study used 6% hydrogen peroxide whitening strips twice daily for 30min over a 2-week period. Common efficacy (digital images) and safety (examination and interview) methods were used across studies. Pooled subject-level data were analyzed using a general linear mixed model to determine overall response and effects of treatment duration on whitening. RESULTS The 148 treated subjects were 18-71 years old, with b* (yellowness) ranging from 12 to 22, and L* (lightness) ranging from 69 to 80. After 1-week strip use, the adjusted mean (S.E.) for Deltab* was -1.6 (0.08), differing significantly from baseline (p<0.0001). After 2 weeks, the adjusted mean (S.E.) for Deltab* was -2.3 (0.07), differing significantly from Week 1 (p<0.0001). The estimated correlation between Weeks 1 and 2 for Deltab* was 0.74. Study-to-study variation contributed less than 2% of Deltab* variability. Results were similar for DeltaL*, with Weeks 1 and 2 estimated means (S.E.) of 1.5 (0.13) and 2.0 (0.12). Occurrence of oral irritation (22%) and tooth sensitivity (20%) did not adversely affect whitening. Other side effects were unremarkable, and only 1 subject (0.7%) discontinued treatment early due to an adverse event. CONCLUSIONS The meta-analysis of multiple studies conducted at a single clinical site over several years establishes consistent, effective and safe vital bleaching with 6% hydrogen peroxide whitening strips.

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 manufacturers 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.

Effects of duration of whitening strip treatment on tooth color: A randomized, placebo-controlled clinical trial

OBJECTIVES A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate efficacy and safety of 6% hydrogen peroxide whitening strip used twice daily over an extended, 6-week period. METHODS After informed consent, 40 eligible adults were randomly assigned to 6% hydrogen peroxide whitening strips (Crest Whitestrips, The Procter & Gamble Company, USA) or placebo strips without peroxide. Treatment was twice daily for 30min, and response was evaluated biweekly after initial (Week 2) and extended (Weeks 4 and 6) use. Tooth color was measured under standardized lighting conditions using digital image analysis, and safety was assessed from clinical examination and interview. Whitening was measured using data derived from digital images taken at baseline compared to post-treatment, with outcomes reported using the CIELAB color notation system. Analysis of variance and covariance were used to assess initial response, and repeated measures regression analysis was used to model color change during sustained use. RESULTS Forty subjects (25-58 years old) started the study. At baseline, L* ranged from 68.0 to 76.8, a* ranged from 8.0 to 11.8, and b* ranged from 16.4 to 23.1. Groups differed significantly (p<0.001) on all color parameters at Week 2 and thereafter, favoring the 6% hydrogen peroxide strips. Week 2 adjusted means+/-SE were -2.1+/-0.2 for Deltab* and 1.9+/-0.2 for DeltaL* for the peroxide group compared to -0.3+/-0.2 for Deltab* and 0.4+/-0.2 for the placebo group. With sustained use (Weeks 2-6), the slope for the peroxide strip was estimated as -0.3 for Deltab* and +0.2 for DeltaL* per week, with both slopes differing significantly from zero (p<0.0001), while slopes for the placebo strip were not significant (p=0.22) and nearly zero. Treatment was generally well tolerated, with adverse events confined to symptoms only. CONCLUSIONS Twice-daily use of 6% hydrogen peroxide whitening strips resulted in teeth becoming lighter and less yellow versus baseline and placebo during initial 2-week use, with no evidence of placebo response during sustained (Weeks 2-6) use.

Placebo-controlled trial evaluating safety with 12-months continuous use of 6% hydrogen peroxide whitening strips

OBJECTIVE To assess the safety and tolerability of 6% hydrogen peroxide whitening strips over 12 months. METHODS 80 adults were randomly assigned equally to one of two treatments: 6% hydrogen peroxide strips or placebo strips. Strips were worn 5 min daily for 12 months. Safety and tolerability were assessed via oral status interviews and oral examinations at baseline and after 1, 2, 3, 6, 9, and 12 months of use. RESULTS Tooth sensitivity and oral irritation were the two most common adverse events. After 12 months use, tooth sensitivity was reported by 10% of subjects in the 6% strip group with a 95% confidence interval (CI) of (2.8%, 23.7%) and 5% of subjects in the placebo group with a 95% CI of (0.6%, 16.9%). The occurrence of reported oral irritation was 0% in the 6% strip group with a 95% CI of (0%, 8.8%) and 2.5% in the placebo strip group with a 95% CI of (0.1%, 13.2%). The occurrence of observed oral irritation was also similar between groups. The groups did not differ significantly (p>0.67) for the percent of subjects with each type of adverse event. In the 6% strip group, two subjects discontinued product use due to an adverse event (tooth sensitivity) compared to no subjects in the placebo group. Groups did not differ significantly (p>0.49) with respect to this outcome. CONCLUSION Use of 6% hydrogen peroxide whitening strips over 12 months resulted in a safety profile similar to that seen with placebo strips.

Placebo-Controlled Clinical Trial of Use of 10% Hydrogen Peroxide Whitening Strips for Medication-Induced Xerostomia

Objective: A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the effectiveness and safety of peroxide-containing strip-based tooth whitening among subjects with medication-induced hyposalivation. Methods: Eligibility for this tooth whitening study was limited to dentate adults taking xerogenic medications with an unstimulated salivary flow ≤0.2 ml/min. After giving informed consent, 42 subjects were randomized using a 2:1 ratio to 10% hydrogen peroxide whitening strips (Crest® Whitestrips® Premium) or placebo strips without peroxide. Strips were used for 30 min twice daily for a 14-day period. Usage was unsupervised, and only the maxillary arch was treated. On days 8 and 15, efficacy was assessed from standard digital images of the anterior dentition and quantified using the Cielab color system, while safety was assessed from interviews and clinical examinations. Results: At day 8, the peroxide group experienced significant (p < 0.001) color improvement relative to baseline and placebo. Adjusted means ± standard errors for yellowness reduction were –1.65 ± 0.115 units for the peroxide group and –0.32 ± 0.170 units for the placebo group. For the increase in lightness, adjusted means ± standard errors on day 8 were 1.53 ± 0.130 units for the peroxide group and 0.37 ± 0.191 units for the controls. Continued strip use through day 15 yielded incremental color improvement for the peroxide group. Mild and transient tooth sensitivity represented the most common adverse events. No subject discontinued treatment due to a product-related adverse event. Conclusion: Twice daily use of 10% hydrogen peroxide whitening strips by adults with medication-induced xerostomia was well tolerated, with significant tooth color improvement evident within 7 days.

Treatment responses to tooth whitening in twins.

The aim of this study was to determine heritability estimates of treatment responses to a 10% hydrogen peroxide strip-based whitening system in twins. Eighty-five twin pairs were randomly assigned to 10% hydrogen peroxide whitening strips or placebo strips without peroxide. Both twins (monozygotic or dizygotic) received the same treatment. Maxillary teeth were treated for 30 minutes twice daily for 7 days. Efficacy was measured objectively as L* (light-dark), a* (red-green), and b* (yellow-blue) color change from digital images at baseline (∆) and day 8. Heritability estimates for tooth whitening treatment responses for changes from day 8 to baseline were obtained using variance-component methodologies. Whitening treatment responses were highly heritable (h(2) = 71.0) for ∆b* and ∆a*(p < .0001), but not for ∆L* (h(2) = 27.0), which was essentially modulated by environmental factors. This study has demonstrated that both genetic and environmental factors significantly contributed to seven-day whitening treatment responses achieved with 10% hydrogen peroxide strips.