The aim of the present cross-sectional investigation was to evaluate percentage of bone loss in patients who had been one year under periodontal maintenance at the Department of Periodontology, Faculty of Dentistry, University of São Paulo by radiographic analysis.Complete sets of periapical radiographs provided data regarding percentage of alveolar bone loss, which was correlated with arches, tooth group and proximal sites. The sample consisted of 27 men and 53 women ranging in age from 16 to 85 years (mean: 48.3 years). A total of 1,120 periapical radiographs (1,970 teeth) were digitized and analyzed with the Image Tool ® software (University of Texas Health Science Center). Bone loss was defined as when the distance between the cemento-enamel junction and the alveolar bone crest was greater than 2 mm. Two examiners (pϽ0.0001) performed radiographic measurements of bone loss.The Greenhouse-Geisser normality test and a univariate analysis of variance were used for statistical analysis.Mean bone loss was 20.60% .)21.21ע( The highest level of bone loss was observed on the distal surface and in the upper arch, as well as in the upper incisors and molars.