Abstract
This study aimed to evaluate the long-term cumulative survival rates (CSR) of implants subjected to immediate loading in the molar regions, stratifying outcomes by jaws (maxilla vs. mandible), opposing dentition status, and location (free-end vs. non-free-end configurations). A retrospective cohort of 75 cases involving immediately loaded implant-supported prostheses in the maxillary and mandibular molar regions utilizing Brånemark Clone implants was followed for up to 6,522 days (approximately 17 years). Implant removal was defined as treatment failure. CSRs were calculated and compared across variables using the log-rank test, and hazard ratios (HRs) were estimated. The level of statistical significance was set at p = 0.05. The mandible had a significantly higher CSR than the maxilla (p ＜ 0.0092; HR = 5.018). Conversely, no statistically significant differences in CSR were observed when stratifying by opposing dentition conditions or free-end versus non-free-end status. Within the limitations of this 17-year follow-up study, immediate loading in the molar region yielded a significantly superior cumulative survival rate in the mandible compared to the maxilla. Opposing tooth conditions and arch positioning did not significantly impact long-term implant survival. Further investigation is warranted to analyze diverse implant systems while accounting for confounding variables, such as the number and distribution of implants and the specific design of the superstructure.
