Preoperative Computed Tomography-derived Bone Densities for Acquired Primary Implant Stabilities

Objectives: The purpose of this study was to evaluate the preoperative computed tomography (CT)-derived bone densities in Hounsfield units (HU) for acquired primary implant stabilities compared to the satisfactory bone densities proposed in the literature. Methods: Fifty-one patients, 18 male (37 implant sites) and 33 female (67 implant sites), who had undergone implant placement between 2003 and 2010 were selected. The data for the different jaw, region, and procedure were using Kruskal-Wallis test and Scheffe's test for multiple comparisons (P < 0.05). Results: The mean bone density (725.7 ± 174.7 HU) for male was significantly higher than that (546.9 ± 209.7 HU) for female (P < 0.01). The mean bone density in maxilla was significantly lower than that in mandible (P < 0.05), and the mean bone densities for the four regions decreased in the following order: anterior mandible (843.6 ± 241.9 HU) > anterior maxilla (640.9 ± 172.7 HU) > posterior mandible (628.2 ± 209.2 HU) > posterior maxilla (486.0 ± 199.2 HU). The mean bone density (630.8 ± 223.1 HU) for the one-stage procedure was higher than that (575.2 ± 198.1 HU) for the two-stage but this difference was not significant (P > 0.05). Conclusions: These limited findings show that the bone densities for acquired primary implant stabilities ranged the proper bone densities proposed in the literature. This study was partly supported by a Grant-in-Aid for Scientific Research (no. 23592887) from the Japan Society for the Promotion of Science (JSPS) and the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan (2011–2013).