Primary Stability Determination of Implants Inserted in Sinus Augmented Sites: 1-Step Versus 2-Step Procedure

Objectives:The aim of this study was to evaluate the primary stability of implants placed immediately after a sinus lift, compared with implants placed in the area treated with a sinus lift 6 months before.Material and Methods:Patients with a residual bone height of at least 4 mm were treated with a 1-stage procedure (group A) and patients with a residual bone height < 4 mm with a 2-stage approach (group B). Sinus lift was always performed with 50% autogenous bone and 50% deproteinized bovine bone mineral. Data recorded included maximum insertion torque (IT), resonance frequency analysis (RFA) values, and bone density, length, and diameter. It was recorded whether an implant was removed within 6 months after insertion.Results:Fourteen patients were included in group A and 16 patients in group B; 96 implants were inserted. Mean IT was 23.77 12.63 Ncm in group A and 26.48 +/- 20.80 Ncm in group B. Mean RFA was 65.25 +/- 4.45 implant stability quotient (ISQ) in group A and 67.92 +/- 10.99 ISQ in group B. No statistically significant differences were found. All implants were osseointegrated.Conclusions:The results show that the implants studied can obtain a sufficient primary stability in both clinical situations without statistically significant differences.