Comparative evaluation of fracture resistance of self adapting PFS and elastic FRC post and core systems – An invitro study

Abstract

Background:  Endodontically treated teeth (ETT) with extensive coronal destruction are more prone to fracture, so restoring these teeth with techniques that will not compromise the integrity of remaining tooth structure with the use of Post and core systems to retain full and final crown restorations seems mandatory. Anatomic posts have been introduced which have better adaptability to the canal anatomy and conserve more amount of tooth structure. Aim: This study was done to compare the fracture resistance of ETT restored with two anatomic post systems elastic FRC post (everStick) and self adapting PFS (Spirapost). Materials and Methods: Twenty single rooted maxillary central incisors were selected for the study. All the samples were endodontically treated and randomly divided into 2 groups (n=10) according to the post system used (PFS post – Group I, FRC– Group II). In all the samples, post space preparation was done and the posts were luted using dual cure resin cement (Para core, Coltene, Mumbai, India).The remaining core was built using composite resin (Filtek, 3M, ESPE, USA). The samples were stored in saline for one week. All the samples were thermocycled for 500 cycles from 5 to 55 ⁰ c ±5 ⁰ c with a dwelling time of 30 seconds in each bath and a transfer time of five seconds. Fracture resistance of the samples was measured using universal testing machine. The obtained data was statistically analyzed by using independent t test. Results: There was no statistically siginificant difference between fracture resistance values of FRC and PFS groups. 30% and 70% of the samples of PFS and FRC showed favourable fractures respectively. Conclusion: In this study it was concluded that fracture resistance of PFS was comparable to that of FRC post. However FRC group showed predominantly more number of favourable fractures.