EFFECT OF INSTRUMENT POWER SETTING DURING ULTRASONIC SCALING UPON TREATMENT OUTCOME

ULTRASONIC SCALERS MAY BE OPERATED at different power settings which may influence the final therapeutic result. The displacement amplitude of the scaling tip may affect scaling efficiency or the degree of root surface damage. This investigation aimed to determine whether there was any difference in periodontal healing, as assessed by standard clinical methods, when an ultrasonic scaler was operated at full or half power in patients suffering from mild to moderate adult periodontitis. Seventeen patients with chronic adult periodontitis were entered into the study and a split mouth design utilized. Quadrant allocation was randomized, 2 quadrants being treated at full power and 2 at half power. At baseline, probing attachment levels, bleeding and plaque indices (BI and PI) were recorded and oral hygiene instruction given. Two weeks later all measurements were repeated and further recordings made at 1, 3, and 6 months post-therapy. Statistical analysis demonstrated no differences between groups at baseline (P > 0.3) for all parameters. At the post-oral hygiene stage, there were significant attachment gains for both experimental groups (P < 0.04), but no differences were found between the groups (P > 0.6). At 6 months, mean attachment gains for the half power and full power groups over baseline measures were 0.5 +/- 0.5 mm and 0.4 +/- 0.3 mm, respectively (P < 0.002), and there were no significant differences between the groups (P > 0.5). The results show that the use of the half power setting was as effective as using the ultrasonic scaler at full power. Further work is required to determine whether the action of the water irrigant is more important than mechanical chipping of the scaler tip during ultrasonic scaling.