The effect of varying concentrations of hydrogen peroxide on bovine enamel and dentine

Abstract

Background: Bleaching has become a popular treatment option for aesthetic management of discolored teeth. Bleaching is a conservative approach in aesthetic dentistry compared to other invasive restorative treatment modalities such as indirect veneers and crowns. While bleaching is successful and effective, several studies have documented structural changes such as increased roughness, decreased microhardness, and decreased enamel strength, as well as a decrease in mineral content (calcium, phosphate, and fluoride) and the emergence of clinical symptoms such as dentin hypersensitivity and gingival irritation.

Aim: The aim of this study was to investigate the effects of varying concentrations of hydrogen peroxide (HP) on bovine enamel and dentine in term of calcium, magnesium, and phosphorous ion release.

Materials and Methods: Bovine enamel and dentine discs were sectioned, prepared and treated with different concentrations of carbamide peroxide (CP) including 10%, 15%, and 20% CP, and 35% HP. Negative control group was saline solution, and the positive control group was vinegar (N=5). All solution samples were analyzed for ion release using a calcium, magnesium and phosphate meter.

Results: Treatment with 35% HP resulted in statistically significant increase in the amount of calcium and magnesium ions released from both enamel and dentin samples (p <0.05 ). Treatment with CP 10-20% caused statistically significant increase in the amount of magnesium and phosphate ions released from enamel and dentin samples (p <0.05).

Conclusions: From the results of this study, it can be concluded that tooth whitening with CP (10-20%) and high concentrations of HP (35%) can have detrimental effects on the structure of both enamel and dentin by increasing the dissolution of their mineral components.