RESUMO
To evaluate the clinical effects of metronidazole-doxycycline gel for treatment of periodontitis, 18 adult patients with periodonti-tis, who had at least 4 mm of probing depth (PD) on the symmetric quadrant, were selected to participate in a randomised study with split-mouth design. Patients of the experimental group were given with metronidazole-doxycycline gel locally once a day for 7 days,while those of the control group were given with metronidazoce stilus. PD, PLI(plaque index), GI(gingival index), BI(bleeding index) were examined on days 0 and 7 of treatment. The results showed that all clinical parametres of the experimental group were better than those of the control group . Therefore, metronidazole-doxycycline gel is effective in the treatment of periodontitis.