Investigation of the long-term prognosis (3-13 Years) of full mouth implant prosthetics combining zygomatic implants based on the all-on-four concept.
TL;DR
Immediate full-arch rehabilitation combining ZIs and CIs achieved high long-term survival; however, palatal platform positioning and systemic disease were associated with ZI failure.
Abstract
Purpose
Zygomatic implants (ZIs) are indicated for severely atrophic maxillae where conventional implant (CI) placement is difficult. Although ZIs show favourable outcomes, factors influencing their survival remain unclear. This retrospective study evaluated implant- and patient-related factors associated with ZI survival in full-arch immediate-loading rehabilitation using the all-on-four concept combining ZIs and CIs.
Methods
A total of 923 implants (323 ZIs and 600 CIs) placed in 203 patients between 2010 and 2021 were analysed. Cumulative survival rates were estimated using the Kaplan-Meier method, and intergroup comparisons were performed using the log-rank test. Cox proportional hazards regression analyses were performed to calculate hazard ratios (HRs). Statistical significance was set at p < 0.05.
Results
Cumulative survival rates at 3-13 years were 94.5% and 95.9% at the patient and implant levels, respectively, for ZIs, and 97.9% and 98.7%, respectively, for CIs. ZIs showed significantly lower implant-level survival than CIs (p = 0.0178). Palatal positioning of the ZI platform was significantly associated with reduced implant-level survival (HR = 18.177, 95% CI: 1.418-233.053, p = 0.026). Systemic disease was significantly associated with reduced patient-level ZI survival after adjustment for sex and smoking status (HR = 14.872, 95% CI: 1.812-122.077, p = 0.012).
Conclusions
Immediate full-arch rehabilitation combining ZIs and CIs achieved high long-term survival; however, palatal platform positioning and systemic disease were associated with ZI failure.