en Dental implant Dental implant Original article Original article <p style="text-align: justify;"><strong><span dir="LTR">Background and Aim:</span></strong><span dir="LTR"> One of the main goals in the fabrication of an implant-supported prosthesis is to build a superstructure with passive fitness. If this fails, it will lead to the failure of the implant components. This study aimed to investigate the effect of Duralay and Pattern Resin splinting materials on dimensional accuracy in the open tray impression technique.</span><br> <strong><span dir="LTR">Materials and Methods:</span></strong><span dir="LTR"> An edentulous acrylic model was developed. In the lateral teeth area, two implants (CMI, Neobiotech Co.) were placed perpendicularly and parallel to each other. The implants were cemented with cyanoacrylate. Pattern</span> <span dir="LTR">Resin (n=10) and Duralay (n=10) were used to splint the impression copings, and the impression was taken using the open tray technique. The main casts (20 pieces) were made with Vel-Mix type IV plaster using a vacuum mixer. The dimensional changes of each group were measured using a multi-axial coordinator. T-test was used to analyze the data.</span><br> <strong><span dir="LTR">Results:</span></strong><span dir="LTR"> The mean dimensional changes of implant position transfer at the x-axis were 5.04&plusmn;0.37 &mu;m for Duralay and 5.58&plusmn;0.13 &mu;m for Pattern</span> <span dir="LTR">Resin. The mean dimensional changes of implant position transfer at the y-axis were 7.01&plusmn;0.49 &micro;m for Duralay and 6.78&plusmn;0.15 &micro;m for Pattern</span> <span dir="LTR">Resin. The mean dimensional changes of implant position transfer at the z-axis were 7.62&plusmn;0.71 &micro;m for Duralay and 6.86&plusmn;0.12 &micro;m for Pattern</span> <span dir="LTR">Resin. T-test showed that the difference between the two groups was not statistically significant (P>0.05).</span><br> <strong><span dir="LTR">Conclusion:</span></strong><span dir="LTR"> According to the results, Duralay and Pattern Resin were not significantly different regarding dimensional changes </span><span dir="LTR">in </span><span dir="LTR">the open tray impression technique. </span></p> Dental Implant, Dental Impression Technique, Splints, Acrylic Resins 23 27 http://jrdms.dentaliau.ac.ir/browse.php?a_code=A-10-708-4&slc_lang=en&sid=1 M Neshandar 10031947532846009771 10031947532846009771 No Associate Professor, Prosthodontics Dept, Member ship of Dental Material Research Center, Faculty of Dentistry, Tehran Medical Sciences, F Baloch 10031947532846009772 10031947532846009772 No Associate Professor, Prosthodontics Dept, Faculty of Dentistry, Tehran Medical Sciences, Ss Mousavisedighi 10031947532846009773 10031947532846009773 No Dentist T Bitaraf taherehbitaraf@yahoo.com 10031947532846009774 10031947532846009774 Yes Assistant professor, Dental Implant Research Center, Dental Faculty, Tehran Medical Sciences,, Islamic Azad University, Tehran, Iran