Prosthodontic Complications of Metal-Ceramic and All-Ceramic, Complete-Arch Fixed Implant Prostheses with Minimum 5 Years Mean Follow-Up Period. A Systematic Review and Meta-Analysis

Purpose The purpose of this systematic review and meta-analysis was to review and analyze the prosthodontic complications, survival, and success of metal-ceramic (MC) and all-ceramic (AC) complete-arch fixed implant dental prostheses (CFIDPs) with a minimum mean follow-up period of 5 years. Methods A structured literature search was conducted using 3 electronic databases (MEDLINE, the Cochrane Library, Web of Science) for clinical studies reporting on prosthodontic complications of metal-ceramic and/or all-ceramic CFIDPs published between 2000 and 2016. This was complemented with hand searching in relevant journals, references, as well as searching in grey literature. Risk of bias analysis for randomized controlled trials was done following the recommendations from the Cochrane Collaboration. Quality appraisal for nonrandomized studies was executed according to the Newcastle-Ottawa scale (NOS). The final selection included only studies with a minimum mean follow-up time of 5 years. Results The electronic databases search yielded 1804 relevant titles and abstracts; 11 studies were finally selected (9 for MC and 2 for AC CFIDPs). Risk of bias in most selected studies was low. Heterogeneity across studies of MC CFIDPs was within acceptable range but not among AC CFIDP studies, so no meta-analysis was performed for the latter. Regarding MC CFIDPs, most studies recorded 100% survival rate (survival range: 92.4-100%, success range: 47-96.7%), with veneer fracture being the most-common complication. Five- and 10-year cumulative complication rates for MC CFIDP veneer fractures were 22.1% and 39.3%, respectively, but with variable confidence intervals. The 2 studies included for AC CFIDPs reported 100% survival rates but differed in success rates, with the one using predominantly monolithic zirconia restorations reporting 90.9%, and the one using bi-layered zirconia reporting 60.4%, with complications attributed to veneer fracture. Conclusions MC and AC CFIDPs presented with veneer fractures as primary complication. This may require significant maintenance. Other complications were negligible after a mean follow-up period of at least 5 years. More long-term studies, especially on all-ceramic CFIDPs are needed.