Primary stability of implants inserted following sinus lift and bone graft in the posterior of the maxilla

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.