The effect of applying potassium chloride solutions at atmospheric pressure on the sensitivity of dentine in man

Clinical Efficacy of Mouthwashes with Potassium Salts in the Treatment of Dentinal Hypersensitivity: A Systematic Review and Meta-analysis

AIM

This systematic review and meta-analysis evaluated whether the home use of mouthwashes containing potassium salts is effective in reducing and controlling dentin hypersensitivity (DH).

METHODS AND MATERIALS

This study is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist and was registered in PROSPERO (CRD42021228410). Randomized clinical trials evaluating the use of mouthwashes containing potassium salt for daily household mouthwash for at least four weeks to reduce DH compared with a control mouthwash were selected, with no limitation on year of publication. Electronic research was carried out in PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library by two independent researchers. One hundred thirty-three articles were obtained, and nine were selected according to the inclusion criteria.

RESULTS

The selected studies evaluated DH through tests of sensitivity to tactile and evaporative stimuli and showed that, for the tactile stimulus, there were no baseline differences between groups (p=0.12; mean difference: -0.33; confidence intervals [CI]: -0.73 to 0.08). However, there were significant differences after two weeks of use (p=0.00001; mean difference: 4.67; CI: 4.53 to 4.81), after four weeks (p=0.00001; mean difference: 13.29; CI: 13.03 to 13.55), and after eight weeks (p=0.00001; mean difference: 8.88; CI: 5.73 to 12.02) favoring the experimental group. The results of the evaporative test showed no differences in the baseline assessment between the two groups (p=0.50; mean difference: -0.02; CI: -0.09 to 0.04), but after four weeks (p=0.00001; mean difference: -0.32; CI: -0.44 to -0.20), and eight weeks of use (p=0.00001; mean difference: -0.42; CI: -0.57 to -0.27) there were differences favoring the experimental group. The incidence of side effects showed no differences between the two groups (p=0.89; mean difference: 1.03; CI: 0.67 to 1.58).

CONCLUSION

The daily use of mouthwashes containing potassium salt is effective in the treatment of dentinal hypersensitivity, as a complementary step to brushing at least twice a day for two weeks, four weeks, and up to eight weeks, without presenting side effects.

Time-course of the effect of potassium oxalate in the treatment of hypersensitive dentine in man

OBJECTIVE

Investigate the cause of hypersensitive dentine (HD) by recording the time course of changes in dentine sensitivity, sensory threshold to electrical stimulation (ET) and pulpal blood flow (PBF) following tubular occlusion using in vitro and clinical experiments.

DESIGN

Nineteen teeth with HD and 13 with normal dentine from 8 participants were evaluated, and the intensity of any pain produced by various stimuli was recorded at different times after oxalate treatment. The participants used a visual-analogue scale (VAS) to indicate the intensity of any pain. The ET and PBF were recorded at the same times.

RESULTS

Preliminary in vitro experiments showed that oxalate treatment had no effect on the method used to record PBF, and blocked the treated tubules immediately after application. Considering teeth with HD, a decrease in the median VAS evoked by all forms of stimulation was observed at all post-treatment times, except immediately after treatment (p < 0.05), while the treatment produced no significant effect in teeth with normal dentine. No significant changes in ET or PBF was observed in any of the groups.

CONCLUSIONS

The effect of oxalate in relieving the symptoms of HD is not only due to a reduction in the intensity of stimulation of sensory receptors sensitive to fluid flow in the dentinal tubules, but also to a reduce in the sensitivity of the receptors that respond to dentine stimulation. There was no evidence that acute pulpitis or central sensitization to pain, which would be associated with changes in PBF or ET, contributes to HD.