Marginal Bone Loss of Dental Implants in Patients with Type 2 Diabetes Mellitus with Poorly Controlled HbA1c Values: A Long-Term Retrospective Study.

Abstract

The objective of this study was to report implant survival rates, marginal bone loss, and the impact of prosthesis type among patients with type 2 diabetes mellitus (DMT2), with high hemoglobin A1C (HbA1c) values. This retrospective study utilized patient medical records from an oral surgeon's office. Patients who had moderately or poorly controlled DMT2 with HbA1c values up to 10% were reviewed. Inclusion criteria were partially or fully edentulous patients diagnosed with DMT2 who were subsequently treated with implant-supported prosthetic restorations. Patients were at least 18 years of age. Exclusion criteria were patients who did not present for annual follow-up visits, patient records with incomplete surgical or restorative data, or nondiagnostic radiographs. All the fixed restorations were cement-retained, and the removable restorations were supported by two to six implants. Marginal bone loss and the consequences of prosthetic type were assessed from the last available radiograph compared with the one taken after the surgical procedure. Data of 357 implants were extracted from the records of 38 patients with HbA1c values (6.9% to 10.0%). The mean follow-up was 7.3 years, with a minimum of 5 years. Six implants failed, yielding a 98.4% overall implant survival rate. The patients were divided into two groups according to the HbA1c values before implant placement. The moderately controlled group included 25 patients with DMT2, with HbA1c values of 6.9% to 8.0%, and the poorly controlled group included 13 patients, with HbA1c values of 8.1% to 10.0%. The overall mean bone loss was 2.02 ± 2.43 mm. In both groups, the maxilla demonstrated more bone loss than the mandible (P < .05). Marginal bone loss in moderately controlled and poorly controlled groups was 1.86 (± 2.21) mm and 2.33 (± 2.85) mm, respectively (P < .05). Removable prostheses also revealed greater bone loss rates compared with fixed prostheses in both groups (P < .05). Patients with high HbA1c values (8.1% to 10.0%) had more marginal bone loss than those with lower HbA1c values. Removable dentures should be reconsidered as a standard treatment option in these patients.