Comparison of histological, clinical and imaging evaluations of the bone quality of different maxillomandibular regions for placement of dental implants

This study aimed to evaluate the bone quality of the different alveolar regions of the maxilla and mandible through of the classification proposed by Leckholm e Zarb (1985) (L & Z), panoramic and periapical radiographs, implant stability quotient (ISQ), insertion torque (IT), microcomputed tomography (micro-CT) and histomorphometric analysis. The secondary objective was to evaluate the correlation between the several methods mentioned above. Sixty edentulous areas were evaluated, being 15 areas from each quadrant of the maxilla and mandible. The bone quality III was the most frequent in the posterior (73.33%) and anterior maxilla (73.33%) and quality II was the most frequent in the posterior (53.33%) and anterior (60.00%) mandible. A significant statistical difference was observed in the optical bone density evaluated through periapical radiographs of the posterior maxilla (2.38 ± 1.06) and posterior mandible (3.84 ± 0.68), in relation to the other alveolar regions (p≤0.015). With the panoramic radiograph no differences were observed between the optical density of the alveolar regions (p= 0.6322). The primary stability of the implants in the posterior maxilla was different from the posterior mandible, both in the evaluation through the TI and ISQ (p<0.05). It was possible to detect differences in the bone quality of the alveolar regions using several micro-CT parameters (BV, p≤0.002; BV/BT, p≤0.044; BS/TV, p <0.05; Tb.N, p<0.01 and Tb.Sp, p <0.05). With the histometry it was possible to detect difference in the amount of bone of the posterior maxilla in relation to the anterior and posterior mandible (p≤0,043). However, there were no differences in osteocyte counts between the alveolar regions (p=0.2946). Concerning the correlation analysis, the optical bone density evaluated by the periapical radiographs correlated with the TI, ISQ and various parameters of the micro-CT (BV, BV/BT, Tb.Th, Tb.N, BS/BV, Tb.Pf and ISM) (rho≤0.471, p≤0.028). In contrast, the ISQ did not correlate with any of the micro-CT parameters. The L & Z classification showed correlation with the optical density evaluated by periapical radiographs, histometry, osteocyte count, TI and several microCT parameters (BS/BV, Tb.Sp, Tb.Pf, BV, BS/TV, Tb.Th, Tb.N) (rho≤0.344; p≤0.042). Those results suggest that the L & Z bone classification and TI can be considered reliable methods for evaluating bone quality. Periapical radiographs are an acceptable method for assessing bone quality. The panoramic radiograph, on the other hand, is not a reliable method for evaluating bone quality. (AU)