The Relationship Between Resonance Frequency Analysis (RFA) and Insertion Torque of Dental Implants: an in Vitro Study

Purpose: The aims of the present study are to correlate the ISQ values, registered by the Osstell ISQ system, with the insertion torque during the placement of the implant, and to assess the influence of the thread initiator on the ISQ values and on the insertion torque. Materials and methods: 140 rough surface implants screw-shaped implants, placed in 10 bovine ribs, were assigned to Group A (using the thread initiator before the insertion of the implant) or Group B (thread initiator was not used). The implants were implantedusing a manual torque wrench so insertion torque was registered. Once the implants were in place, primary stability was measured by means of RFA with the Osstell ISQ. Results: When the thread initiator was used (group A), the mean insertion torque was 24,36 ± 14,88 N and when the thread initiator was not used (group B) the mean insertion torque was 35,30 ± 10,51N. The mean ISQ of the thread initiator group was 69,14 ± 8,39 and of the non thread initiator group was 72,17 ± 5,76. Pearson’s correlation coefficient was 0,587 (p<0,05) for group A and 0,193 (p<0,11) for group B. Conclusions: It seems that the fact of using or not the thread initiator have no influence in the ISQ values. However, the IT decreased when the thread initiator is employed.