Comparison of spiramycin and tetracycline used adjunctively in the treatment of advanced chronic periodontitis.

This study was designed to compare both clinical and microbiological changes during the treatment of advanced periodontal disease with mechanical debridement, with or without the adjunctive use of either spiramycin or tetracycline. The study, which included 96 patients with advanced periodontitis, was performed as a controlled double-blind parallel randomized trial. All patients received thorough scaling and root planing as well as adjunctive placebo or spiramycin or tetracycline. Probing depth measurements, attachment level changes, plaque level, gingival crevicular fluid, bleeding on probing and microbiological evaluation were carried out at baseline, 2-, 8-, 12- and 24-week visits. Seventy-nine patients (24 placebo, 27 tetracycline and 28 spiramycin) completed the study. At 24 weeks there were no intergroup differences in the improvement of any of the clinical parameters. Spiramycin was the only antibiotic which produced a significantly greater decrease in the proportion of spirochaetes than the placebo group at the 24-week visit. It was concluded that mechanical debridement alone was sufficient in decreasing the subgingival bacteria to a level which would result in the return to periodontal health. The study was not long enough to determine whether or not the difference in spirochaete level was an indication that the spiramycin group would have maintained the benefits of treatment for a longer time.