A Retrospective Analysis of Maxillary Overdentures with Nonsplinted Implants

To evaluate the survival rate of implants and prostheses as well as the complications associated with implant overdentures (IODs) for edentulous maxillae retained by nonsplinted implants.

A total of 76 patients who had received and retained maxillary IODs for at least 6 months between 2006 and 2021 were included in the study. A comprehensive review of patient charts was done to assess the implant and prosthodontic outcomes in these patients. Descriptive data were compiled, and statistical analysis of each variable was performed. Correlation between categorical variables was done using Spearman's rank correlation with a two-tailed significance test.

Ten implants failed in 7 patients, resulting in an implant survival rate of 96.9% following prosthesis delivery. The prosthesis survival rate was 78.9%, with 16 of 76 patients needing a remake of their prosthesis. The most common technical complication was tooth debonding, accounting for 21.2% of technical complications. A correlation analysis found that certain opposing dentitions contributed to an increase in the number of technical complications associated with the maxillary IODs (r[75] = 0.24) (P < .05).

Maxillary IODs with nonsplinted implants showed high implant survival rates comparable to those reported in previous studies. However, the prosthesis survival rate was lower than reported in the literature for maxillary IODs with splinted or nonsplinted designs. It is recommended that the patient's opposing dentition be sufficiently considered during treatment planning to reduce overloading factors and resultant technical complications.