Compliance as a prognostic indicator. II. Impact of patient's compliance to the individual tooth survival.

Background: Existing evidence concerning the validity of an appropriate regular periodontal maintenance (PM) regimen and the role of patient compliance is controversial and inconsistent. The objectives of this study are to identify the impact of patient compliance (complete versus erratic) on alveolar bone loss and tooth survival.

Methods: A retrospective study was conducted using data from 295 patients with >or=20 years of observation, which included treatment and >or=15 years of maintenance therapy, in a private practice in Yamagata, Japan. Subject-level variables and tooth-level variables were recorded at the initial visit, the reevaluation visit, and the final visit. In total, 7,502 teeth in 295 subjects met inclusion criteria and were divided into two groups: non-molar teeth (n = 5,585) and molar teeth (n = 1,917). A tooth-level multivariate survival model and multiple logistic regression model using the method of generalized estimating equations were constructed to analyze the effects of compliance and periodontal maintenance intervals on tooth loss and alveolar bone loss, respectively.

Results: Of 7,502 teeth, 284 molar teeth and 364 non-molar teeth were lost. Molar teeth had an approximately 30% reduction in risk of tooth loss for complete compliance, with 2-year compliance classification achieving statistical significance (P = 0.033), and 30% compliance classification approaching statistical significance (P = 0.072). Complete compliers under 30% compliance classification showed over 50% reduction in the risk of alveolar bone loss among non-molars (P = 0.015).

Conclusion: Complete patient compliance with increased frequency of periodontal maintenance is important for improved dental prognosis through reduction of tooth loss among molars and minimization of alveolar bone loss among non-molars.