Comparison of Initial Stability Parameters and Histomorphometric Analysis of Implants Inserted Into Extraction Sockets: Human Fresh Cadaver Study

Purpose: To evaluate the initial stability parameters (insertion torque value [ITV], implant stability quotient [ISQ], and Periotest value [PTV]) of implants inserted just after tooth extraction in human fresh cadavers and to examine the relationship between initial stability parameters and bone-to-implant contact ratio (BICR). Materials and Methods: This study was undertaken in three fresh human cadavers, which were divided into six groups. A total of 48 sites (four maxillary sites and four mandibular sites in each of the six groups) were selected for the experiment. Extractions were performed under minimal surgical trauma and each manufacturer's recommended formal surgical procedure was followed to place implants. Initial stability parameters (ITV, ISQ via two different instruments, PTV) were measured. Specimens were prepared to analyze histologic findings and BICR. Results: A total of 44 implants were included in this study. Statistically significant correlations were found between ITV and ISQ1 (r = 0.555, P .001), ITV and ISQ2 (r = 0.398, P .007), ITV and PTV (r = -0.452, P .002), ISQ1 and ISQ2 (r = 0.603, P .001), ISQ1 and PTV (r = -0.576, P .001), and ISQ2 and PTV (r = -0.423, P .004). No statically significant correlations were found between BICR and the initial stability parameters. Conclusion: The initial stability parameters have statistically significant correlations to each other. However, the initial stability parameters do not seem to present a reliable parameter to predict the area of bone-to-implant contact. Keywords: bone-to-implant contact, immediate implantation, initial stability, insertion torque, Periotest values, resonance frequency analysis