Primary tooth enamel loss after manual and mechanical microabrasion

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.

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.

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).

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.