microleakage of different post systems and a custom adapted fiber post.

the effects of closely adapting a prefabricated fiber to the post space remain unknown. the purpose of this study was to quantify the microleakages of a custom adapted fiber-reinforced post, a prefabricated quartz fiber post and a cast post using nondestructive methods.sixty-five extracted human premolars were endodontically treated and randomly divided into three groups (n=15), which were restored using a cast post-and-core, a custom adapted fiber post (refropost) with a microhybrid microfiller resin composite (gradia), or a prefabricated quartz fiber post (dt light post) and two groups of control (n=10). all groups were cemented using a dual polymerizing resin cement (panavia f2.0). a composite core (z100) was used for the fiber posts. the microleakage was calculated for the experimental and control groups before and after thermal cycling and cycling loading using a radiotracer solution (thallium 201 chloride) and a gamma counter device. data were subjected to statistical analysis of anova and tukey hsd at significant level of p< 0.05.significantly lower microleakage values were found for the cast post-and-core (mean value =16.04 ×10(4)) and custom adapted fiber post groups (mean value=14.36×10(4)). thermal cycling and cyclic loading had no significant effect on the microleakage value of any tested group.post systems with improved adaptation showed similar microleakage to casting posts.