Clinical and microbiological effects of adjunctive, locally delivered chlorhexidine on patients with chronic periodontitis.

OBJECTIVE: The impact of a locally delivered chlorhexidine chip (Periochip) on clinical and microbiological parameters of chronic periodontitis requires further documentation. The aim of the present study was to investigate the effects of the chip as an adjunct to mechanical treatment of chronic periodontitis. METHODS: Fifty patients with chronic periodontitis were randomized into two groups. The test group (n = 25) received scaling and root planing and adjunctive Periochip in four pockets. The control group (n = 25) received scaling and root planing only. Clinical indices (probing depth, probing attachment level, bleeding on probing) were assessed at baseline, three and six months. Subgingival samples were analyzed at baseline, three weeks, three and six months after treatment for levels of eight bacterial species using "checkerboard" DNA-DNA hybridization. RESULTS: The targeted difference of probing depth of 2 mm between groups was not observed. Both treatments resulted in improvement of clinical indices and non-statistically significant differences were observed between the two groups at any time point, with the exception of bleeding on probing at three months (ANOVA, p < 0.05). No major differences were observed concerning levels of important periodontal pathogens (Mann-Whitney test, p < or = 0.05). CONCLUSIONS: In this small, six-month, phase 4 trial, no differences in mean probing depth reduction or "red-complex" periodontal pathogens were detected for patients with chronic periodontitis treated with adjunctive chlorhexidine chip (single administration) as compared to patients treated with scaling and root planing alone.