Quantitative analysis of dental enamel removal during a microabrasion technique

Objective: To quantify, by means of profi lometry, the removal of dental enamel during the use of a microabrasion technique involving the use of hydrochloric acid and manual abrasion with a plastic spatula. Method: Thirty six specimens obtained from human third molars were polished to obtain fl at surfaces and divided into 3 groups (n = 12) according to the different treatments received: A placebo treatment with deionized water as a negative control (CG); microabrasion with 6.6% hydrochloric acid, OpalustreTM (G1); and microabrasion with 6% hydrochloric acid, Whiteness RMTM (G2). The microabrasion was performed in a standardized manner by submitting the specimens to 4 cycles of 10 seconds each and manual abrasion using a plastic spatula (200 g load). The loss of enamel surface was measured after each cycle of treatment by contact profi lometry. Results: Enamel loss was already observed after the fi rst 10 seconds of abrasion with hydrochloric acid in both treated groups (G1 and G2). After 4 abrasions of 10 seconds each, the average fi nal enamel losses in the treated groups were 46.04 μm (G1) and 54.65 μm (G2). In the G1 and G2 groups, a signifi cant increase in enamel wear was detected in each cycle in comparison to the control group (p ≤ 0.05). A signifi cant difference in enamel loss between G1 and G2 was found after 30 and 40 seconds of microabrasion. Relevance: The results of this study provide objective data for safely performing the microabrasion technique on dental enamel using hydrochloric acid and manual abrasion using a plastic spatula.