Effect of local metronidazole application on periodontal healing following guided tissue regeneration. Clinical findings.

The effect of periodontal healing after guided tissue regeneration (GTR) in association with local application of metronidazole gel was evaluated in this study. Twelve patients with one pair of vertical periodontal bone defects of comparable size and configuration participated in the study. In a matched paired design, the test defects were treated by GTR using expanded polytetrafluoroethylene (ePTFE) membranes in combination with local application of metronidazole gel. The controls were treated in the same way except for application of metronidazole. During the first month of membrane implantation, no statistically significant differences between test and control surfaces were noted with respect to inflammation of the marginal gingiva. Six weeks following insertion, the membranes were removed. Six months after removal of the membrane, the median gain in probing attachment level as a percentage of the initial defect depth was 92% for test defects and 50% for control defects (P = .001). No statistically significant differences were found between test and control sites regarding plaque, bleeding on probing, reduction in pocket depth, gain in bone height, or recession of the gingival margin. In conclusion, the results of the present study indicate that local application of metronidazole gel has a beneficial effect on healing of periodontal vertical defects treated by guided tissue regeneration.