Clinical and microbiologic changes following the irrigation of periodontal pockets with metronidazole or stannous...

The purpose of this investigation was to determine the efficacy of subgingival irrigation with 1.64% stannous fluoride or 0.5% metronidazole solutions on the clinical and microbiologic parameters of adult periodontitis as compared with scaling and root planing. Twelve patients with moderate to advanced periodontitis were selected, and one pocket of a minimum 5-mm probe depth in each quadrant received one of the following treatments: (a) one session of scaling and root planing at the beginning of the experiment, (b) stannous fluoride irrigation, (c) metronidazole irrigation, and (d) saline irrigation. Results showed that scaling and root planing provided significantly better improvement in most of the clinical parameters than did the two tested irrigants. Saline also provided a statistically significant improvement, but only during the first 4 weeks. The four methods of treatment provided a sustained decrease in spirochetes, with a concomitant increase in coccoid cells. It was concluded that although subgingival irrigation with 1.64% stannous fluoride or 0.5% metronidazole solutions improved periodontal health, they never achieved the same efficacy as scaling and root planing and, therefore, should not be substituted for fastidious mechanical subgingival plaque and calculus removal.