Radiographic Crestal Alveolar Bone Changes in Previously Treated Periodontitis Subjects

Objectives: To investigate patterns of tooth loss and radiographic crestal alveolar bone changes in a group of periodontitis patients who were treated more than 5 years previously. Methods: Chinese periodontitis patients, mean age 51 (±10 SD) years who had been treated in a teaching hospital 10 (±3) years previously and who were responsible for their own periodontal maintenance arrangements were recalled (n=164; 93 females). Tooth loss was noted. Radiographic crestal alveolar bone levels per unit root length on mesial and distal aspects of all teeth were measured by Schei ruler on pre-treatment and review panoramic radiographs. Results: Overall, 276 (6.2%) out of 4466 teeth were lost during maintenance. Many subjects (42.1%) experienced tooth loss. Rates of tooth loss by tooth type were: upper molars (1st 15.9%, 2nd 13.8% and 3rd 12.5%); lower molars (1st 13.9%, 2nd 10.6% and 3rd 8.7%); lower central incisors (7.4%); and the remaining tooth types (≤6.5%). Baseline mean radiographic bone levels were 52.4% (±21.6%) for teeth lost during maintenance and 70.3% (±15.1%) for surviving teeth, (t-test, p<0.05). Among surviving teeth, there were significant bone level changes from baseline to recall at distal of upper and lower second and third molars and mesial of lower third molars (paired t-test, p<0.0025). Conclusions: Many treated periodontitis patients responsible for their own periodontal maintenance experienced tooth loss over a period of 10 years. Teeth presenting with more advanced radiographic crestal alveolar bone loss at baseline appeared more likely to be lost in the post-treatment period. Hospital clinicians perhaps should consider arranging periodontal maintenance at the hospital for those treated periodontitis patients who present with advanced bone loss on teeth which are treated with the aim of being retained.