en Prosthodontics Prosthodontics Original article Original article <div> <table align="center" hspace="0" vspace="0"> <tbody> <tr> <td style="padding: 0cm 12px; text-align: justify;" valign="top"><span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Background and Aim</span></span></span></b><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">:</span></span></span></b><b> </b><span style="font-size:9.0pt"><span style="font-family:" verdana="">This study aimed to assess the effect of horizontal cantilever on microgap and microleakage at the implant-straight abutment interface in cement-retained crowns. &nbsp;&nbsp;</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Materials and Methods:</span></span></span></b> <span style="font-size:9.0pt"><span style="font-family:" verdana="">In this experimental study,<b> </b>12 implant-abutment assemblies and 12 cement-retained crowns were evaluated. The implant fixtures were bone-level, and had 10 mm length and 4 mm diameter. Straight titanium abutments had 7 mm length, 4 mm diameter, and 1 mm gingival height with Morse-Taper connection. Two groups were evaluated: 6 cement-retained crowns with a horizontal cantilever (test group) and 6 cement-retained crows without a horizontal cantilever (case group). The assemblies underwent load cycling in a chewing simulator. Cyclic load (75 N) with 1 Hz frequency was applied along the longitudinal axis of each specimen to the triangular ridge between the mesiobuccal and mesiolingual cusps of the crown. The amount of microgap before and after cyclic loading, and the microleakage score after immersion in fuchsine were evaluated under a light microscope.&nbsp; Data were compared by t-test (alpha=0.05).</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Results:</span></span></span></b><b> </b><span style="font-size:9.0pt"><span style="font-family:" verdana="">The change in microgap after cyclic loading compared with before was not significant in the control group (P=0.724). However, in the case group, the amount of microgap significantly increased after cyclic loading compared with before (P=0.000). Microleakage in the case group was significantly greater than that in the control group (P=0.019).</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Conclusion:</span></span></span></b> <span style="font-size:9.0pt"><span style="font-family:" verdana="">Horizontal cantilever caused horizontal microgap and increased the microleakage at the implant-straight abutment interface. </span></span></span></span></td> </tr> </tbody> </table> </div> Dental Implants, Single-Tooth, Dental Implant-Abutment Design, Dental Leakage 162 170 http://jrdms.dentaliau.ac.ir/browse.php?a_code=A-10-823-2&slc_lang=en&sid=1 Arezu Babasafari arezu.b.ab@gmail.com 100319475328460012000 0000000254804886 Yes Department of Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Ezatollah Jalalian dr_e_jalalian@gmail.com 100319475328460012001 0000000259378687 No Department of Fixed Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Arash Zarbakhsh arashz1350@gmail.com 100319475328460012002 0000000182718697 No Department of Fixed Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Abdolkarim Rostamian abdolkarim.rostamian@gmail.com 100319475328460012003 000000028956494X No Department of Fixed Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Shaghayegh Golalipour sh.golalipour@gmail.com 100319475328460012004 0000000197361846 No Department of Fixed Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Sotoudeh khorshidi Atenakhorshidi94@gmail.com 100319475328460012005 0000000203697865 No Department of Fixed Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran