Primary tooth enamel loss after manual and mechanical microabrasion.

PURPOSE This study's purpose was to assess the amount of dental enamel loss on primary incisors after manual or mechanical microabrasion with a phosphoric acid/pumice paste. METHODS Ten exfoliated primary maxillary incisors were bisected faciolingually and the resulting 20 halves were randomly assigned to 2 groups: group 1 (N = 10)-manual technique (plastic spatula); and group 2 (N = 10)-mechanical technique (rubber cup attached to a low-speed handpiece). Microabrasion was performed on the buccal surface using an abrasive paste prepared with 37% phosphoric acid and pumice. Ten 20-second applications alternated with 20-second risings were performed in each group. Enamel thickness measurements made under stereomicroscopy before and after microabrasion were analyzed statistically by analysis of variance and pairwise t test. RESULTS There was a statistically significant difference (P = .003) between the manual and mechanical techniques. The mechanical technique produced a mean enamel loss of 274.16 microm (66% of total enamel thickness), while the mean enamel loss with the manual technique was 152.59 microm (39% of total enamel thickness). CONCLUSION Manual microabrasion using a plastic spatula removed less enamel, but was sufficient to eliminate most superficial stains and defects, and may be a viable option for the microabrasive technique on primary teeth.