Potassium oxalate oral rinses for long-term relief from dentinal hypersensitivity: Three randomised controlled studies.

OBJECTIVES: To evaluate effectiveness of oral rinses containing dipotassium oxalate monohydrate (KOX) in relieving dentinal hypersensitivity (DH) after 8 w use adjunctive to brushing. METHODS: Three 8-week, randomised, controlled, double-blind, parallel-group, single-centre studies were conducted in adults with DH. In each study, participants were randomised to one of two experimental rinses or a placebo in a matrix design, such that each experimental rinse was evaluated in two studies. Rinses A (pH 4.5) and B (pH 7.0) contained 1.5% KOX and were fluoride-free; Rinse C (pH 4.5) contained 2.0% KOX and 45 ppm fluoride as NaF; the placebo rinse (pH 4.5) did not contain KOX or fluoride. Participants brushed with a fluoride dentifrice for 1 min, briefly rinsed with water, then rinsed with their assigned oral rinse for 1 min twice daily for 8 w. DH was assessed at baseline and following 4 and 8 w use by response to an evaporative (air) stimulus (evaluated by Schiff sensitivity score and a 10-point visual rating scale) and a tactile stimulus (Yeaple probe). RESULTS: All rinses in each study were associated with statistically significant improvements from baseline in measures of DH after 4 and 8 w treatment. However, between-treatment comparisons were inconsistent across the studies, with only Study 3 demonstrating a significant difference between the experimental (Rinses B and C) and placebo rinses. A number of treatment-related adverse events (all mild) were reported. CONCLUSIONS: Rinses containing 1.5-2.0% KOX did not consistently demonstrate a benefit over placebo in relieving DH after 8 w use. CLINICAL SIGNIFICANCE: While favourable results were found in one of the investigations, this suite of studies shows that the possibility of inconsistent results exists even with the best designed and executed trials.

Efficacy of an experimental toothpaste containing 5% calcium sodium phosphosilicate in the relief of dentin hypersensitivity: An 8-week randomized study (Study 1).

PURPOSE: To evaluate the efficacy of an experimental toothpaste containing 5% (w/w) calcium sodium phosphosilicate (CSPS) in relieving dentin hypersensitivity (DH) compared with control toothpastes containing no known anti-sensitivity ingredients. METHODS: This was the first of two exploratory, randomized, four-treatment, examiner-blind, parallel-design, single-site, 8-week studies in healthy subjects with self-reported and clinically diagnosed DH. The experimental toothpaste contained 5% CSPS with a modified surfactant system, developed to enhance its organoleptic properties. Efficacy was evaluated against an abrasivity-matched placebo formulation (0% CSPS) with additional abrasive silica replacing the CSPS, and two commercially available fluoride toothpastes as controls. After an initial lead-in period, subjects were randomized to one of the four study treatments and instructed to brush twice daily for the next 8 weeks. DH was assessed at baseline and following 4 and 8 weeks of treatment by response to tactile and evaporative (air) stimuli, and using a Dentine Hypersensitivity Experience Questionnaire (DHEQ; a validated quality-of-life measure for DH). RESULTS: A total of 134 subjects were randomized and completed the study. All treatments demonstrated statistically significant reductions in sensitivity from baseline at Week 4 and Week 8 for each clinical measure of sensitivity (all P ≤ 0.001). The 0% CSPS toothpaste demonstrated small but statistically significant reductions in Schiff sensitivity score compared with the other study toothpastes at Week 8 (all P< 0.05), whereas the experimental 5% CSPS toothpaste significantly improved the tactile threshold at Week 4 compared with the 0% CSPS toothpaste (P = 0.0467). The DHEQ responses did not reveal any consistent statistically significant within-treatment changes from baseline or between-treatment differences. Correlation analysis showed weak-to-moderate associations between the DHEQ outcomes and clinical endpoints. Study treatments were well tolerated. The treatment differences observed in this exploratory study were small and inconsistent between measures. The reasons for the inconsistencies are not clear but may be related to the properties of the abrasivity-matched 0% CSPS formulation, with the increased level of dental silica conferring an advantage in terms of reducing DH. The ability of dental silicas to occlude exposed dentin tubules and thereby reduce DH has been demonstrated in previous studies, and may warrant further clinical investigation.

A randomized trial of ethyl lauroyl arginate-containing mouthrinse in the control of gingivitis.

AIM: This 4-week, single-centre, randomized, examiner-blind, controlled study investigated the efficacy and safety of 0.15% ethyl lauroyl arginate (LAE)-containing mouthrinse in adults with mild-to-moderate gingivitis. MATERIAL AND METHODS: Subjects were randomized to use 0.15% LAE-containing mouthrinse or 5% hydroalcohol-negative control twice daily after brushing with standard fluoride toothpaste. Plaque, gingivitis and bleeding were assessed at baseline and Weeks 2 and 4. The oral microflora was analysed at baseline and Week 4. RESULTS: Eighty-seven subjects were randomized to treatment. The 0.15% LAE-containing mouthrinse was associated with statistically significantly (p < 0.001) greater reductions in mean plaque and gingivitis scores versus the negative control at Week 2 (difference [95% confidence interval]: plaque 0.83 [0.64, 1.02], 29.1%; gingivitis 0.11 [0.07, 0.14], 4.8%) and Week 4 (co-primary endpoints: plaque 1.23 [1.07, 1.39], 42.6%; gingivitis 0.23 [0.19, 0.28], 10.7%). Bleeding-index scores were significantly (p < 0.001) reduced versus the control at Weeks 2 (by 0.04 [0.03, 0.06], 36.3%) and 4 (by 0.06 [0.04, 0.08], 50.9%). No shifts were detected in the oral microflora. There were no treatment-related adverse events. CONCLUSIONS: The 0.15% LAE-containing mouthrinse was well tolerated and significantly reduced plaque, gingivitis and bleeding when used as an adjunct to tooth brushing for 4 weeks.

Randomised clinical efficacy trial of potassium oxalate mouthrinse in relieving dentinal sensitivity.

OBJECTIVE: The study aimed to determine the efficacy in relieving dentinal sensitivity of 4 weeks' treatment with an alcohol-free mouthrinse comprising 1.4% potassium oxalate (KO) (Listerine® Advanced Defence Sensitive; LADS), compared with negative and positive controls. METHODS: Subjects were randomised to one of three treatments: LADS mouthrinse - twice-daily toothbrushing with Crest® Cavity Protection Regular toothpaste, rinsing with water and then 10 mL LADS mouthrinse, followed by expectoration; negative control (twice-daily brushing with Crest Cavity Protection Regular toothpaste); or positive control (twice-daily brushing with Sensodyne® Original desensitising toothpaste). Dentine sensitivity was assessed at baseline and after 2 and 4 weeks by Yeaple probe (tactile pressure; patient-reported discomfort by visual analogue scale [VAS]), air blast (VAS) and global subjective sensitivity (VAS). Oral tolerance was monitored throughout the study. RESULTS: At 2 weeks, subjects treated with the positive control and LADS mouthrinse showed significant reductions (p<0.05) in sensitivity scores versus the negative control. At 4 weeks, sensitivity decreased by 110% in the positive-control subjects versus negative-control subjects (p<0.001); sensitivity decreased by 80% in subjects receiving LADS mouthrinse versus negative-control subjects (p<0.05). No serious treatment-related oral adverse events were reported. CONCLUSIONS: The positive control (Sensodyne Original) significantly reduced sensitivity compared with the negative control (Crest toothpaste alone), thus validating the study. The LADS mouthrinse (1.4% KO mouthrinse) significantly reduced sensitivity compared with the negative control, suggesting that LADS mouthrinse was responsible for the clinical effect observed. The treatments were well tolerated. CLINICAL SIGNIFICANCE: To our knowledge, this is the first randomised clinical study to demonstrate the efficacy of a KO-containing mouthrinse (LADS) in relieving dentinal sensitivity.

The efficacy of an experimental dentifrice containing 0.454% w/w stannous fluoride in providing relief from the pain of dentin hypersensitivity: an 8-week clinical study.

PURPOSE: To compare the efficacy of a 0.454% w/w stannous fluoride containing anhydrous dentifrice and a negative control dentifrice containing 1,000 ppm fluoride (as sodium monofluorophosphate) at reducing dentin hypersensitivity over an 8-week period, following twice daily brushing. METHODS: This was a randomized, examiner blind, two-treatment arm, stratified (by maximum baseline Schiff sensitivity score), parallel design, single-site study in 118 subjects, who had at least two sensitive teeth, and met all the criteria at the screening and baseline visit. The study was conducted in Las Vegas, NV, USA. Tactile threshold (Yeaple Probe) and evaporative (air-blast) sensitivity (with Schiff sensitivity scale) were employed as clinical measures to compare the efficacy of the test dentifrice containing 0.454% w/w stannous fluoride to the negative control (Colgate Cavity Protection) at reducing sensitivity at Weeks 4 and 8. RESULTS: 117 subjects completed the clinical study. At the 4- and 8-week time points, between treatment analyses demonstrated the test dentifrice to be significantly better at relieving subjects' sensitivity, for both validated clinical measures, compared to the negative control (at 4 weeks Schiff P < 0.0001 tactile threshold P < 0.0001; at 8 weeks Schiff P < 0.0001; tactile threshold P < 0.0001).