A CLINICAL AND MICROBIOLOGICAL COMPARISON OF THE EFFECTS OF WATER AND 0.02-PERCENT CHLORHEXIDINE AS COOLANTS DURING ULTRASONIC SCALING AND ROOT PLANING

Abstract The maxillary teeth of 10 patients with moderately advanced chronic periodontitis were treated in a split‐mouth design study. The baseline examination included plaque and bleeding scores, probing depths and probing attachment levels. 2 sites in each quadrant were selected for dark‐field microscopic analysis. Each quadrant was randomly assigned to test or control and instrumented with an ultrasonic sealer using either 0.02% chlorhexidine or water as the coolant. Measurements were repeated 2, 6 and 10 weeks later, together with additional plaque sampling. Ultrasonic instrumentation with either chlorhexidine or water was equally effective in reducing bleeding scores and improving probing attachment levels. 42% of chlorhexidine‐ and 38.7% of water‐treated sites showed gains of 1 mm or more in clinical attachment. Mean reductions in probing depth were similar (0.9 mm chlorhexidine, and 0.8 mm water). At the final examination, the chlorhexidine‐treated quadrants had significantly more sites with probing depths in the 1–3 mm category and less in the >3 mm category than the control quadrants (P<0.05). Both treatments reduced the microscopic counts of motiles and spirochaetes, resulting in a subgingival microbiota consistent with periodontal health. The results indicate that chlorhexidine has a slight adjunctive effect in the reduction of pocket depth when used as a coolant during ultrasonic root planing for the treatment of chronic periodontitis. Copyright © 1990, Wiley Blackwell. All rights reserved