Survival Rates, Technical Complications and Dimensions of Monolithic Zirconia Fixed Complete Arch Dental Prostheses

Abstract

OBJECTIVE: The primary objective of this study was to assess the survival and complication rates of monolithic zirconia implant-supported fixed full dental prostheses (IFCDPs) in completely edentulous patients following a minimum 1-year clinical follow-up. Additionally, the study sought to evaluate associations between risk indicators, structural dimensions, and quality-of-life outcomes. MATERIALS AND METHODS: This observational, single-center retrospective cohort study included a convenience sample of 44 participants who received 61 zirconia IFCDPs at Tufts University School of Dental Medicine (TUSDM). Data on demographics, clinical variables, technical complications, and prosthesis dimensions were collected. Descriptive statistics were calculated, and associations between independent variables and complications were analyzed using generalized estimating equations (GEE). Statistical analyses were performed using SPSS v.28 (IBM Corp., Armonk, NY, USA) and SAS 9.4 (SAS Institute Inc., Cary, NC, USA). RESULTS: The study included 44 participants (45.5% female, 54.5% male; mean age 67.07 (SD=12.1) years) with a mean prosthesis use duration of 28.67 (SD=18.32) months. The majority (72.7%) did not use a nightguard, and 25% reported bruxism. Opposing dentition included natural teeth (13.1%), implant-supported prostheses (50.8%), removable prostheses (14.8%), a combination of teeth and implants (19.7%), and implant overdentures (1.6%). Of the 61 prostheses, 52.5% were maxillary, and 47.5% were mandibular. Minor technical complications included Ti-base decementation (13%), chipping (12%), loss of access hole material (13%), and wear of prosthetic screws (11.5%). Major complications were infrequent, with fracture of screws (2%) and fracture of frameworks (3%). The overall prosthesis survival rate was 93.44%, with a mean total complication rate of 0.8 (SD=1.15)events per prosthesis. Structural analysis identified reduced dimensions at critical cross-sections as potential contributors to fractures. CONCLUSION: This study demonstrated a 93.44% survival rate for monolithic zirconia IFCDPs over an average follow- up period of 28.67 months. While the prostheses showed high reliability, minor technical complications were relatively common, highlighting the need for routine maintenance. The findings underscore the importance of prosthesis design and risk factor consideration in treatment planning. Larger, multicenter studies with longer follow-up periods are recommended to validate these findings and provide greater insights into the long-term performance of zirconia prostheses.