Clinical and microbiological effects of local chlorhexidine applications

AIM: To study the effects of an application of chlorhexidine varnish (40%) on dental plaque. DESIGN: Randomised controlled clinical trial. SUBJECTS: 40 patients (50% females), aged 25-34 years after undergoing any necessary restorative treatment. Exactly one half of these individuals practiced good oral hygiene, the efforts of the others were poor. METHOD: Test groups received a chlorhexidine varnish application, the control group received a placebo varnish. Initially and after 2 and 6 weeks, a modified Dentocult SM-test, bleeding on probing, and a plaque index (Quigley-Hein) were recorded. RESULTS: In contrast to the control group, improvements in plaque index and bleeding on probing scores were found in patients with poor oral hygiene. The results of the Dentocult SM-tests showed a considerable reduction of streptococcus colonisation. The test group with good oral hygiene showed only slight improvement of the examined indices after chlorhexidine application. The index parameters of all patients of the placebo groups remained unchanged over the examination time period. CONCLUSION: The application of a chlorhexidine varnish reduced the quantity of the Streptococcus mutans colonies significantly and improved clinical parameters in patients with elevated plaque accumulation.