Relations between the bone density values from computerized tomography, and implant stability parameters:: a clinical study of 230 regular platform implants

Aims: The objective of this study was to determine the relationship between bone density, insertion torque, and implant stability at implant placement. Materials and Methods: One-hundred and eight patients were treated with 230 Branemark System implants. A computerized tomography (CT) machine was used for pre-operative evaluation of the jaw bone for each patient. The maximum insertion torque values were recorded with the OsseoCare equipment. Implant stability measurements were performed with the Osstell machine for only 142 implants. Results: The mean bone density and insertion torque values were 721 254 Hounsfield unit (HU) and 39.1 +/- 7 N cm for 230 implants, and the correlation was significant (r = 0.664, p < 0.001). The mean bone density, insertion torque, and resonance frequency analysis values were 751 +/- 257 HU, 39.4 +/- 7 Nc m, and 70.5 +/- 7 implant stability quotient (ISQ), respectively, for 142 implants. Statistically significant correlations were found between bone density and insertion torque values (p < 0.001); bone density and ISQ values (p < 0.001); and insertion torque and ISQ values (p < 0.001). Conclusion: The bone density values from pre-operative CT examination may provide an objective assessment of bone quality, and significant correlations between bone density and implant stability parameters may help clinicians to predict primary stability before implant insertion.