Prosthesis Survival, Complications, and Maintenance of Telescopic-Crown-Retained Removable Dental Prostheses and Root-Cap-Retained Overdentures: A Retrospective Cohort Study.

Objectives: To compare prosthesis survival, complication-free survival, and maintenance-free survival between telescopic-crown-retained dentures (TCDs) and root-cap-retained overdentures with ball attachments (RCDs), and to evaluate associated clinical factors. Methods: This retrospective single-center cohort study included 654 unique patients, each contributing one eligible prosthesis (406 TCDs and 248 RCDs). Mean follow-up was 4.15 years for TCD and 2.75 years for RCD. Time-to-event outcomes were analyzed using Kaplan-Meier methods and multivariable Cox regression. Adjusted analyses were restricted to prostheses supported by one to three abutments. Results: Unadjusted prosthesis survival was higher for TCD (p = 0.0001), whereas prosthesis type was not clearly associated with loss after adjustment (RCD vs. TCD: HR = 1.28; 95% CI: 0.75-2.19). Single-abutment support and, in sensitivity analysis, point-like support were associated with higher loss hazards. The higher adjusted complication hazard for RCD was attenuated in sensitivity analysis. RCDs were consistently associated with earlier maintenance (average HR = 1.75; 95% CI: 1.43-2.13), with exploratory analyses suggesting a greater difference during early follow-up and among single-abutment prostheses. Conclusions: The support situation appears more relevant to prosthesis loss than the retention concept alone. RCDs show earlier first documented maintenance requirements, whereas evidence for an independent difference in complication risk is model-dependent.