Push out strengths of a double tapered post system with 3 different cements
The aim of the study was to determine which of the three resin cements would produce the highest debond stress values with a double-tapered fibre post system. In the past, conventional parallel- sided prefabricated or cast metal posts have been used, which has considerable mechanical strength but lacks aesthetic capabilities. Post preparation techniques usually compromise the fracture strength of the treated anterior tooth. Double- tapered post systems ensure that anterior mutilated teeth can be restored and retained without compromising aesthetics or excessively weakening the remaining dental tissues. There are in-vitro results that support the strength of the double- tapered design, as well as the aesthetics of the material but there is little evidence regarding the retentive capabilities of the posts and which cement will ensure the best results (Grandini et al., 2008; Nakamura et al., 2005). Literature suggests that the two main causes for failure of a post system are root fracture and debonding of the post in the root canal (Toman et al., 2009; Radovic et al., 2008). The type of cement and cementation technique will have a significant influence on the treatment success of post and core restorations. This study compared the debond stresses required to remove a double- tapered post system from a prepared post space with 3 different cements to assess which cement will be most resistant to the post debonding.