en پروتزهای دندانی Prothtodontics پژوهشي Research <b> Objective:</b> 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. <div>  <b>Materials and Methods:</b> 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. </div><div>  <b>Results</b>: Significantly lower microleakage values were found for the cast post-and-core (mean value =16.04 ×104 ) and custom adapted fiber post groups (mean value=14.36×104). Thermal cycling and cyclic loading had no significant effect on the microleakage value of any tested group.</div><div><b> Conclusion:</b> Post systems with improved adaptation showed similar microleakage to casting posts. </div><div><hr><p class="MsoNormal" style="text-align: left direction: ltr unicode-bidi: embed"><b>Source: </b>Journal of Dentistry of Tehran University of Medical Sciences<span style="font-size: 15.5pt line-height: 115% font-family: Verdana, sans-serif color: rgb(250, 250, 250) background-color: rgb(101, 111, 115) background-position: initial initial background-repeat: initial initial"><o:p /></span></p> <p class="MsoNormal" style="text-align: left direction: ltr unicode-bidi: embed"><a href="http://jdt.tums.ac.ir/index.php/jdt/article/view/487" target="_blank"><font color="#0000ff">Full Text</font></a></p></div> Dental Microleakage; Thallium Radioisotop; Tooth Preparation, Prosthodontic 0 0 http://idai.ir/browse.php?a_code=A-10-32-971&slc_lang=en&sid=1 Farideh Geramipanah 10031947532846004219 10031947532846004219 No Dental Implant Research Center, Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran susan Mirmohamadrezaee mirmoham@sina.tums.ac.ir 10031947532846004220 10031947532846004220 Yes Dental Research Center and Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medi-cal sciences, Tehran, Iran Saman Fallahi Sichani 10031947532846004221 10031947532846004221 No Department of Prosthodontics, Faculty of Dentistry, Hamedan University of Medical sciences, Tehran, Iran Babak Fallahi Sichani 10031947532846004222 10031947532846004222 No Research Institute for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Leyla Sadighpour 10031947532846004223 10031947532846004223 No Dental Research Center and Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medi-cal sciences, Tehran, Iran