Calculus removal from multirooted teeth with and without surgical access. (I). Efficacy on external and furcation surfaces in relation to probing depth.

: The purpose of this study was to evaluate the efficacy of the calculus removal from multirooted teeth after closed root planing, open root planing and use of a rotary diamond for the furcation area. The effect of pocket depth on the effectiveness of calculus removal was also examined. 30 first and second lower molars scheduled for extraction, with a calculus index > or = 2 and a degree II or III furcation involvement, were divided into 3 groups: 10 molars were scaled and root planed using a closed approach; 10 molars were scaled and root planed using an open approach; 10 molars were scaled and root planed with an open approach and rotary diamond was used for removal of deposits in the furcation area. After extraction, the teeth were assessed in a stereomicroscope and the % of residual calculus was calculated on external and furcation surfaces. The % of residual calculus on the external surfaces was significantly higher after closed than open root planing (p = 0.002). Pocket depth affected the effectiveness of scaling and root planing, with more residual calculus observed for depths > or = 7 mm for both groups. Differences between the 3 groups in the % of residual calculus on furcation surfaces were statistically significant (p or = 7 mm but the difference was significant only in the closed group (p = 0.006).(ABSTRACT TRUNCATED AT 250 WORDS)