The Effect of Removable Partial Denture Placement for Diabetic Patients

Objectives: The purpose of this study was to evaluate the alveolar bone density loss and survival rates of abutment teeth in patients with diabetes mellitus (DM).
Methods: We recruited patients who had received prosthodontic treatment with removable partial dentures (RPDs) and supportive periodontal treatment (SPT) for at least twice a year over a period of 5 years. Patients were divided into with or without DM groups based on HbA1c results. We evaluated abutment tooth and supporting alveolar bone density loss. Bone density loss was analysed using the digital subtraction radiography method. We compared the grey level (GL) between patients with and without DM using the Mann–Whitney U test. Kaplan–Meier analysis was used to evaluate 5-year survival probabilities for the abutment teeth. Cox regression models were used to estimate the influence of the independent variables on the survival of the abutment teeth, taking multicollinearity into account.
Results: We included 235 patients (147 females, 88 males; mean age 65.52 years) in this study. We analysed 281 clasp-retained RPDs and 739 abutment teeth. There were no significant differences in the 5-year survival rates of RPDs and abutment teeth between patients with and without DM. Conversely, there was a significant difference in mean GL between groups in the distal crestal area (p = 0.048). Multivariate analysis showed that abutment survival was significantly associated with age (HR: 2.04) and devitalized teeth (HR: 5.50).
Conclusions: Within the limitations of this retrospective study, we found that abutment teeth had favourable survival rates irrespective of the presence of DM. However, digital subtraction radiographic analysis confirmed evidence of bone density loss in the distal crestal alveolar bone of the abutment tooth at 5 years after RPD placement in patients with DM, even with continuous SPT.