Effectiveness of subgingival scaling and root planing: single versus multiple episodes of instrumentation.

This study evaluates the effectiveness of subgingival scaling and root planing comparing the effect of a single instrumentation to the effect of three instrumentations. A total of 35 teeth in 15 patients were selected; 15 were scaled once (Group A), 15 were scaled three times (Group B), and 5 were used as controls (Group C), representing teeth that were not instrumented. The Group A and B teeth were chosen in the same patient based on random selection. All the teeth were scored by the calculus index of the periodontal disease index. Six surface locations were probed to determine probing depth. The level of the gingival margin was marked on the teeth to locate supra- and subgingival calculus after extraction. The Group A and B teeth received the initial episode of scaling and root planing for not more than 10 minutes, then only the Group B teeth received two additional instrumentations of not more than 5 minutes each. The additional instrumentations were performed 24 hours after the initial scaling. The scaled and control teeth were extracted immediately after the third instrumentation period. The teeth were washed with water and stained with methylene blue. They were viewed under a stereomicroscope which had a tenth grid on its eyepiece. Assessments were made involving the total counts and percents of the surfaces covered with calculus on the scaled and unscaled teeth. The results demonstrated no significant difference in the effectiveness of calculus removal between single and multiple episodes of scaling and root planing. Similar results were found for the total amount of calculus removed, the calculus removed from individual surfaces, and the calculus removed from various probing depth levels.