Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 3 4 2016 12 15 258 263 EN Mehdi Sezavar Department of Oral and Maxillofacial surgery, Azad University of Medical sciences, Dental Branch, Tehran, Iran. Mohammad Reza Soleimanpour Department of Oral and Maxillofacial surgery, Azad University of Medical sciences, Dental Branch, Tehran, Iran. Fahimeh Koshki Department of Oral and Maxillofacial surgery, Azad University of Medical sciences, Dental Branch, Tehran, Iran. Seyedeh Zahra Shakeri Department of Oral and Maxillofacial surgery, Azad University of Medical sciences, Dental Branch, Tehran, Iran. Mohammad Moharrami Craniomaxillofacial Research Center (CMFRC), Shariati Hospital, Department of Oral and Maxillofacial surgery, Tehran University of Medical Sciences, Tehran, Iran. 2016 11 26 2016 11 26 Introduction: This study aimed to compare the primary stability of implants inserted conventionally with those inserted following sinus lift plus bone graft. Materials and Methods: The data consisted of periotest scores from 12 patients (7 women, 5 men, mean age of 47.8±10.4) and 24 implants. Each patient had 1 implant which was inserted conventionally and another using sinus lift (lateral window) and bone graft, therefore, each patient rolled as control as well as case group for him/herself. Eight patients had surgery on the right side and other 4 on the left side. After 4 months of surgery, primary stability was measured by periotest at 3 points. Radiographs also were served to evaluate success rate of each technique. The patients were collected from a private clinic during 8 months. Mann-Whitney U test was served for analysis; P-value less than 0.05 was considered as statistically significant. Results: The difference between diameters and lengths of implants between case and control group was insignificant (p>0.05). The mean score of periotest for case and control group was -2.73±1.52 and -4.31 ±1.99 respectively. Although the primary stability was higher in the control group and Mann-Whitney U analysis showed a significant difference (p<0.05), but as both scores were negative, primary stability was acceptable in the case group as well. Conclusion: Despite the lower primary stability of implants inserted in regions with a sinus lift and graft, the technique is acceptable and clinically efficient. Key words: Implant, Sinus lift, Graft, Primary stability. https://jcr.tums.ac.ir/index.php/jcr/article/view/109 https://jcr.tums.ac.ir/index.php/jcr/article/download/109/136