Marginal adaptation of CAD-CAM and heat-pressed lithium disilicate crowns: A systematic review and meta-analysis.

STATEMENT OF PROBLEM

Lithium disilicate crowns can be manufactured by computer-aided design and computer-aided manufacturing (CAD-CAM) or with the heat-pressed technique. The outcome of studies comparing the effect of the manufacturing method on the marginal adaptation of these crowns is not clear.

PURPOSE

The purpose of this systematic review and meta-analysis was to investigate the effect of the CAD-CAM system and pressing technique on the marginal adaptation of lithium disilicate crowns.

MATERIAL AND METHODS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A literature research was conducted in MEDLINE via PubMed and Scopus databases, relevant journal sites, and the authors' collected references, from January 2009 to April 2019.

RESULTS

The electronic and manual searches that could be read in full totaled 24 studies; of which, 9 were included in the systematic review and meta-analysis, 7 of which were in vitro and 2 in vivo. Statistical analyses were conducted by using Review Manager software program. Meta-analyses were performed with the random effects model (α=.05). In vitro studies showed no difference in the manufacturing (P>.001; 95% confidence interval -0.687 to 0.632), and no significant difference was found for in vivo studies (P=.7, 95% confidence interval 0.00 to 54.77). In the joint analysis of the in vivo and in vitro articles, there was a significant difference between the manufacturing methods (P<.001).

CONCLUSIONS

Differences were detected between the marginal adaptation of lithium disilicate crowns fabricated with the CAD-CAM system and the pressing technique, but the accuracy values were clinically acceptable.