[Nonsurgical treatment: a long-term study].

This retrospective study was carried out on 20 patients with periodontal lesions treated by the same operator by scaling root planing. The investigation was designed to study the variability of the level of attachments through different charts of probing before and after treatment over a period of 5 years maintenance. Through efficient scaling and root planing different results were obtained according to sites of different localisations and depth. It shows the uncertain and occasional characteristics of periodontal lesions, and gives useful informations for treatment choices and regular maintenance program.