[Effects of subgingival antimicrobial irrigation in chronic periodontitis--clinical observation].

One week prior to the establishment of baseline records, 144 sites with a probing pocket depth of 5-7 mm in 13 periodontitis patients were treated with plaque control and root planning. Sites with periodontitis involvement in each patient were divided, by split mouth design, into 4 quadrants. Each quadrant was irrigated subgingivally with either 0.05% metronidazole or 0.05% ornidazole, or 0.2% chorhexidine, or 0.9% normal saline (control) once every 2-3 days for 4 weeks. The plaque index, sulcus bleeding index, probable pocket depth and gingival index were assessed at the baseline and at 4 weeks, 8 weeks and 12 weeks following initial preparation. All 4 clinical parameters in the ornidazole treated group showed significant improvement as compared with baseline values, but the improvements were not maintained to the end of the study. Except for improvement in the sulcus bleeding index and the gingival index in the ornidazole group, which was superior to that of the metronidazole group at the 4th week, there were no significant differences in other parameters between the ornidazole, metronidazole and chlorhexidine groups at the irrigation sites. From these data we can tentatively conclude that subgingival irrigation with ornidazole in deep pockets is more effective than metronidazole or chlorhexidine in nonsurgical periodontal therapy.