A systematic review on the accuracy of zirconia crowns and fixed dental prostheses
The aim of this study was to review the fit and assess the accuracy of tooth-supported single and multi-unit zirconia fixed dental prostheses.
• Background: The fit of zirconia restorations has been reported in several studies, but the accuracy of the manufacturing process is seldom discussed or used when drawing conclusions on the fit.
• Materials and methods: A literature search of articles published in PubMed between 2 March 2013 and 1 February 2018 was performed using clearly defined inclusion and exclusion criteria. 841 articles were found and 767 were excluded after screening the title and abstract.
After fulltext analysis another 60 articles were excluded which left 14 articles to be included for data extraction. Fit was the mean of distances reported in the studies and accuracy was the fit minus the pre-set spacer
• Results: For marginal gap of single crowns and multi-unit FDPs combined, the fit was 83lm and the accuracy was 59lm. The internal gap fit was 111lm and the accuracy 61lm. For the total gap, the fit was 101lm, and the accuracy of the zirconia restorations was 53lm.
• Conclusions: Within the limitations of the present systematic review the fit of zirconia single crowns and multi-unit FDPs may be regarded as clinically acceptable, and the accuracy of the manufacturing of zirconia is 60lm for marginal, internal, and total gap. Also, digital impressions seem to be associated with a smaller gap value.
