Influence Of Cement Thickness On The Adhesive Property Of Glass Fiber Post:a Study Of Micro-push-out Test And Finite Element Analysis

The debonding of fiber post from root canal is the common form for endodontic restoration failure, and the polymerization shrinkage stress caused by resin cement curing is the primary cause of this phenomenon. The former researchers had found that the cement thickness could affect the bond strength significantly, but they failed to ensure whether a thicker cement layer can promote the bond strength or not. In this study, we introduced a customized 1-piece glass fiber post and core manufactured with CAD/CAM to cope with this problem by using CAD reverse design technology was used to perform a shifty cement thickness. Then the conclusion that lower bond strength and smaller deviation related to thicker cement layer was observed through micro push-out test. Moreover, by analyzing specimens’fracture mode of each group, we discovered that the relationship between cement thickness and fracture mode. Finite Element Analysis(FEA) verified the results obtained by experiment. Because of the 1-piece glass fiber post and core’s excellent adaptation, we can expect a well bond property by using it to endodontic restoration.