The effect of polishing technics on surface smoothness and plaque accumulation on stainless steel crowns.

The purpose of tins study was to evaluate the surface produced when stainless steel crowns were polished by several technics and to compare the ability of the various polished surfaces to resist bacterial plaque accumulation. Twenty-one Unitek and twenty-one Ion primary molar stainless steel crowns were divided into several groups containing three crowns each. Each group was polished with a different procedure. The crowns were suspended in culture medium and inoculated with Streptococcus mutans. Plaque accumulation on each crown was scored by visual assessment. One crown from each group was prepared for SEM evaluation. There were no significant differences in the plaque accumulation on the two types of crowns or in the ability of the various polishing procedures to retard the formation of bacterial plaque. The SEM revealed irregular shaped gouges, scratches, and protuberencss on all crowns polished with rotary instruments. The smoothest surface was noted on the crowns polished in an acid passivator.