fa In Vitro Effect of Zirconia and Zirconia Enriched Glass Fiber Composite Posts on Fracture Resistance of Endodontically Treated Teeth ترمیمی Cosmetic and Restorative Dentistry پژوهشي Research <p style="background-color: rgb(239, 243, 250)"><strong style="margin: 0px padding: 0px border: 0px"><i style="margin: 0px padding: 0px border: 0px">Objective: </i></strong>Despite the advantages of esthetic posts, lack of studies on their fracture resistance has limited their clinical use. This study aimed to compare the effect of two types of esthetic posts namely zirconia and zirconia enriched glass fiber composite posts on fracture resistance of endodontically treated teeth against compressive forces.</p><p style="background-color: rgb(239, 243, 250)"> <strong style="margin: 0px padding: 0px border: 0px"><i style="margin: 0px padding: 0px border: 0px"> Methods: </i></strong>This <i style="margin: 0px padding: 0px border: 0px">in vitro</i> study was conducted on 20 mandibular premolar roots cut at the cementoenamel junction (CEJ). The roots were endodontically treated and randomly divided into 2 groups of 10. After post space preparation, in group 1 zirconia posts (CosmoPost, Ivoclar, Liechtenstein) and in group 2 zirconia enriched glass fiber composite posts (Ice Light, Danville, USA) were cemented in the roots using a dual-cure resin cement (Panavia F 2.0, Kuraray, Japan) according to the manufacturer’s instructions. The teeth were restored with composite resin cores (Lumiglass, RTD, France) using a prefabricated polyester matrix. After periodontal ligament (PDL) simulation by elastic polyether impression material (Impregum, 3M ESPE, USA), specimens were mounted in acrylic resin and subjected to 1195 Instron universal testing machine. Compressive load was applied at a 90° angle relative to the long axis of the teeth at a crosshead speed of 1mm/min until fracture. Since the data were normally distributed, t-test was used for statistical analysis.</p><p style="background-color: rgb(239, 243, 250)"> <strong style="margin: 0px padding: 0px border: 0px"><i style="margin: 0px padding: 0px border: 0px"> Results: </i></strong>The fracture resistance was 816.69 (120.89) N for zirconia posts and 843.76 (120.93) N for zirconia enriched glass fiber composite posts and these values were not significantly different (<i style="margin: 0px padding: 0px border: 0px">p</i>=0.62). Fractures in group 2 were restorable.</p><p style="background-color: rgb(239, 243, 250)"> <strong style="margin: 0px padding: 0px border: 0px"><i style="margin: 0px padding: 0px border: 0px"> Conclusion: </i></strong>The fracture resistance of zirconia and zirconia enriched glass fiber composite posts was not significantly different and both types of posts can be successfully used.</p><hr><p class="MsoNormal" style="text-align: left direction: ltr unicode-bidi: embed"><b>Source: </b>Journal of Dental School Shahid Beheshti University of Medical Sciences </p> <p class="MsoNormal" style="text-align: left direction: ltr unicode-bidi: embed"><a href="http://jds.sbmu.ac.ir/browse.php?a_id=1410&sid=1&slc_lang=en" target="_blank"><font color="#0000ff">Full Text</font></a></p> Endodontically treated teeth, Fracture resistance, zirconia enriched glass fiber composite post, Zirconia post., 0 0 http://idai.ir/browse.php?a_code=A-10-32-2959&slc_lang=fa&sid=1 Arash Zarbakhsh 100319475328460013754 100319475328460013754 No Dept. of Prosthodontics, Implant Research Center, Dental Branch, Islamic Azad University of Medical Sciences, Tehran, Iran. Ezzatollah Jalalian 100319475328460013755 100319475328460013755 No Dept. of Prosthodontics, Implant Research Center, Dental Branch, Islamic Azad University of Medical Sciences, Tehran, Iran Azita Mazaheri Tehrani 100319475328460013756 100319475328460013756 No Dept. of Prosthodontics, Implant Research Center, Dental Branch, Islamic Azad University of Medical Sciences, Tehran, Iran. Mona Norozi monanorozy@yahoo.com 100319475328460013757 100319475328460013757 Yes