This meta-analysis provides robust evidence that micro-rough 6-mm-short dental implants are a predictable treatment option, providing favorable survival rates. The failures encountered with 6-mm-short implants were predominantly early and their survival in the mandible was slightly superior.
Objectives The aims of this study were set as follows:1. To provide verifiable criteria to categorize the ceramic fractures into non-critical (i.e., amenable to polishing) or critical (i.e., in need of replacement) 2. To establish the corresponding survival rates for alumina and zirconia restorations 3. To establish the mechanism of fracture using fractography Materials and methods Fifty-eight patients restored with 115 alumina-/zirconia-based crowns and 26 zirconia-based fixed dental prostheses (FDPs) were included. Ceramic fractures were classified into four types and further subclassified into "critical" or "non-critical." Kaplan-Meier survival estimates were calculated for "critical fractures only" and "all fractures." Intra-oral replicas were taken for fractographic analyses. Results Kaplan-Meier survival estimates for "critical fractures only" and "all fractures" were respectively: Alumina single crowns: 90.9 and 68.3 % after 9.5 years (mean 5.71 ± 2.6 years). Zirconia single crowns: 89.4 and 80.9 % after 6.3 years (mean 3.88±1.2 years). Zirconia FDPs: 68.6 % (critical fractures) and 24.6 % (all fractures) after 7.2 and 4.6 years respectively (FDP mean observation time 3.02±1.4 years). No core/framework fractures were detected. Conclusions Survival estimates varied significantly depending on whether "all" fractures were considered as failures or only those deemed as "critical". For all restorations, fractographic analyses of failed veneering ceramics systematically demonstrated heavy occlusal wear at the failure origin. Therefore, the relief of local contact pressures on unsupported ceramic is recommended. Occlusal contacts on mesial or distal ridges should systematically be eliminated. Clinical relevance A classification standard for ceramic fractures into four categories with subtypes "critical" and "noncritical" provides a differentiated view of the survival of ceramic restorations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.