[The effectiveness of surgical compared to nonsurgical treatment of periodontal disease. 1. Molar surfaces. 24-month study].

The response to the treatment and periodontal maintenance during a period of 24 month, was investigated in 17 patients with periodontal disease by comparing root debridement alone versus root debridement plus surgery, in the molar flat surfaces sites. A total of 443 sites were controlled every 3 month and recorded every 6 month in regard to plaque indice bleeding frequency, probing pocket depth and changes of probing attachment level. The results analysed using linear regression, demonstrated that in sites with initial probing depth 0-3 mm or 4-6 mm. at 24 th months there was an evident improvement in the clinical conditions of the periodontal tissues, independent in the treatment modality. Sites with initial probing depth of 7 or more mm., however, showed a different result. In this sites, the plaque indice and the probing pocket depth were considerable reduced, but the frequency of bleeding and the clinical attachment level showed a negative result, in those sites treated by root debridement alone compared with root debridement plus surgery.