Comparison of Fracture Resistance of Three Recent Esthetic Post and Core Systems with Cast Metal Post and Core to Compressive Loading - An in vitro Study

Introduction The primary function of a post is to provide retention for a core, which is essential for the longevity of restorations placed on endodontically treated teeth. With the increasing use of anterior all ceramic restorations to meet the aesthetic needs, there is a need for tooth colored posts and cores that are as good as if not better than their metallic non-aesthetic metal counterparts. Aim To determine and compare the fracture resistance of three recently introduced esthetic post and core systems with a cast metal post and core to compressive loading using a clinically related test method. Materials and Methods Forty maxillary central incisors were selected, sectioned and their roots endodontically treated and assigned to 4 experimental groups (n=10). The cast metal post and core (CMPC) served as control group. The other groups were zirconium dioxide post and ceramic core group (ZCER), zirconium dioxide posts and composite core group (ZCOM) and glass fiber post and composite core group (GFCOM). The post spaces were prepared, posts were seated and cores were formed. A compressive load was applied to the inclined surface on each specimen until failure occurred and measured in Newtons. Data were analysed by One-way Analysis of Variance (ANOVA) and intergroup comparison was done using Tukeys Post Hoc test. Results CMPC and ZCER groups exhibited the highest fracture resistance and the values were 680.6 N and 630.03 N respectively. ZCOM group exhibited fracture resistance greater than GFCOM but less than ZCER and CMPC. Conclusion CMPC and ZCER groups were found to be more fracture resistant than the ZCOM and GFCOM group. Aside from its desirable esthetic properties, the ZCER group demonstrated high resistance to fracture.