A randomised clinical study to measure the anti-erosion benefits of a stannous-containing sodium fluoride dentifrice

Recent Development of Active Ingredients in Mouthwashes and Toothpastes for Periodontal Diseases

Periodontal diseases like gingivitis and periodontitis are primarily caused by dental plaque. Several antiplaque and anti-microbial agents have been successfully incorporated into toothpastes and mouthwashes to control plaque biofilms and to prevent and treat gingivitis and periodontitis. The aim of this article was to review recent developments in the antiplaque, anti-gingivitis, and anti-periodontitis properties of some common compounds in toothpastes and mouthwashes by evaluating basic and clinical studies, especially the ones published in the past five years. The common active ingredients in toothpastes and mouthwashes included in this review are chlorhexidine, cetylpyridinium chloride, sodium fluoride, stannous fluoride, stannous chloride, zinc oxide, zinc chloride, and two herbs—licorice and curcumin. We believe this comprehensive review will provide useful up-to-date information for dental care professionals and the general public regarding the major oral care products on the market that are in daily use.

Is the Erosion-Protective Effect Still Maintained when Tin Concentrations Are Reduced in Mouth Rinse Solutions?

OBJECTIVE

As a preventive measure, tin (Sn2+)-containing products have a great potential to prevent enamel surface loss during erosive challenges, but adverse effects of high Sn2+ concentrations, such as astringent feeling of the teeth, are reported. Therefore, the main aim of this in vitro study was to develop a solution with lower Sn2+ concentrations that can still prevent dental erosion.

METHODS

A total of 162 enamel specimens were prepared from human premolars, which were selected from a pool of extracted teeth. The specimens were randomly distributed to 9 groups (each group n = 18 enamel specimens) according to the different test treatments: a humid chamber (no treatment) as the negative control, the commercial Elmex® Erosion Protection mouth rinse as the positive control, and 7 solutions either with lower Sn2+ concentrations and/or containing flavoring. The experiment included 4 cycles, consisting of pellicle formation by incubating the specimens with 200 μL of human saliva at 37°C for 1 h, then placing the specimens in the treatment for 2 min (60 mL, 30°C, shaking at 70 rpm), and later submitting them to an erosive challenge for 1 min in citric acid (60 mL 1%, pH 3.6, 30°C). Surface hardness was measured with a Vickers diamond and surface reflection intensity was measured with a reflectometer.

RESULTS

The control group performed significantly worse than all other solutions containing Sn2+. In general, there were no significant differences among the Sn2+-containing groups, and they presented similar protective effects on the enamel even when Sn2+ concentrations were reduced and flavorings were added.

CONCLUSION

Sn2+ concentrations in mouth rinses may be lowered to 200 ppm without compromising the anti-erosive properties of the solution.

Randomized in situ clinical trial evaluating erosion protection efficacy of a 0.454% stannous fluoride dentifrice

OBJECTIVES

To assess the protective effects of a 0.454% stabilized stannous fluoride dentifrice and a marketed triclosan dentifrice against enamel erosion in a 10-day in situ model.

METHODS

This was a double-blind, randomized, 2-treatment, 4-period, crossover in situ trial involving healthy adult participants. Participants were randomized to a treatment sequence involving the following products: a highly bioavailable 0.454% stannous fluoride dentifrice (Procter & Gamble) and a marketed dentifrice control containing 0.24% sodium fluoride and 0.3% triclosan (Colgate-Palmolive). Each study period took place over 10 days. Participants wore an intra-oral appliance retaining two polished human enamel samples for 6 hours per day. Two times per day they swished with the assigned dentifrice slurry and four times per day they swished with 250 mL of orange juice (25 mL per minute) over a 10-minute period. Contact profilometry measurements were made for each sample at baseline and day 10 to determine surface change.

RESULTS

Thirty-six participants were enrolled and 33 completed the study (mean age = 40.5 years). The stannous fluoride dentifrice demonstrated 93.5% less enamel loss than the NaF/triclosan dentifrice (P < 0.001) at Day 10, with median enamel loss of 0.097 µm and 1.495 µm, respectively. Both products were well tolerated.

CONCLUSION

The stannous fluoride dentifrice demonstrated significantly greater erosion protection efficacy relative to the NaF/triclosan dentifrice in this randomized in situ clinical trial.

Antierosive Effect of Topical Fluorides: A Systematic Review and Meta-Analysis of In Situ Studies

BACKGROUND:

The effectiveness of the application of topical fluorides in prevention of erosive tooth wear has been an issue of controversy in the literature. The objective of this systematic review was to assess in situ studies investigating the effects of using topical fluorides on prevention of erosive tooth wear

MATERIAL AND METHODS:

Two electronic databases PubMed/MEDLINE and Cochrane Central Register of Controlled Trials were searched. Eligibility criteria included in situ-controlled studies that assessed the effect of the erosive process without additional tooth brushing. The search involved English-written articles only. A total of 684 potentially relevant titles and abstracts were found after removal of duplicates, of which 22 full-text articles were selected. Seventeen studies were included in the qualitative synthesis of which 6 studies included in the meta-analysis. The following data were obtained for each study: authors, year of publication, country, study design, periods of study, duration, blinding, interventions (type/concentration/form), tooth substrate, location of the intraoral appliance, number of samples attached to each appliance, type of acidic media used for erosive challenge, duration of erosive challenge, subjects (number/age/sex), reported side effects -if any-, measuring device, amounts of tissue loss.

RESULTS:

The risk of bias of the included studies was assessed using the Cochrane Collaboration tool for assessing the risk of bias. A meta-analysis of the present study was performed using Comprehensive Meta-Analysis version 2.2.048 software.

CONCLUSION:

The use of oral hygiene products containing AmF/NaF/SnCl2 or NaF may be effective in the prevention of erosive tooth wear.

Effect of toothpaste containing amine fluoride and stannous chloride on the reduction of dental plaque and gingival inflammation. A randomized controlled 12-week home-use study

OBJECTIVES

This single-centre, controlled, randomized, double-blinded clinical study in parallel groups was performed to assess the efficacy of an experimental toothpaste on plaque and gingivitis.

METHODS

In adult subjects with gingivitis, amine fluoride/stannous chloride toothpaste (test) and monofluorophosphate toothpaste (control) were applied twice daily by regular toothbrushing at home. Evaluations of plaque index (PI), gingival index (GI), modified sulcus bleeding index (mSBI) and safety took place at baseline and after 3 and 12 weeks of study product use. After study completion, all subjects received a dental prophylaxis. A descriptive statistical analysis included means and standard deviations. Unpaired t tests compared index reductions between groups at a significance level of 0.05.

RESULTS

Intention-to-treat analysis included 240 out of 241 subjects. Baseline mean PI was reduced by 0.87 ± 0.35 in the test group and by 0.65 ± 0.41 in the control group. Within-group differences and between-group differences in index reduction were statistically significant (P < 0.001). Mean GI and mSBI were reduced significantly over time (P < 0.001) with no clinically meaningful differences between groups.

CONCLUSIONS

Both toothpastes reduced plaque and gingivitis statistically significant and clinically meaningful over 12 weeks. Compared to the control toothpaste, application of the amine fluoride/stannous chloride toothpaste led to a clinically meaningful and more pronounced plaque reduction.

Clinical enamel surface changes following an intra-oral acidic challenge

OBJECTIVES

Investigation of early enamel erosion using replica impressions to compare changes in enamel surface topography in vivo prior to and over a 24 h period following acid challenge.

METHOD

A single treatment, blinded, enamel replica clinical study was undertaken in 20 healthy subjects. Replica tooth impressions were taken at baseline, following acid challenge and 2, 4, 7 and 24 h post challenge. Subjects consumed 500 ml of acidic soft drink over 30 min. Scanning electron microscopy of surface tomography was characterised with a descriptive 5 point scale by four judges. Duplicate impressions were taken to assess reproducibility.

RESULTS

18 subjects had scorable sequences. Descriptive analyses showed erosive changes following acid consumption and reparative changes in the subsequent 24 h period. Comparing baseline replica to the 24 h replica, there were no significant differences (p=0.26) in tooth surface characteristics. Comparing the replica taken immediately following acidic challenge with the subsequent replicas at 2, 4, 7 and 24 h, showed clear reduction of erosive effects on the enamel surface at 2 h (p=0.02) and a highly significant reduction at 4, 7 and 24 h (p<0.001).

CONCLUSION

This methodology demonstrated the ability to follow the progression and recovery of early erosive enamel lesions over 24 h being accurate and reproducible. This study suggests enamel repair commences within 2 h following a substantial acidic challenge and is completed 4-24 h later. After 24 h, the tooth surface appeared visibly indistinguishable from the original tooth surface, suggestive of a recovery process occurring.

CLINICAL SIGNIFICANCE

Healthy erosive lifestyles often culminate in tooth wear. The time taken for enamel remineralisation following acidic challenge is unknown however, this study suggests the repair process is relatively slow following a substantial acidic challenge, and at least 4-24 h should elapse prior to further acidic consumption to allow for recovery.