Quantitative assessment of interradicular bone density in the maxilla and mandible: implications in clinical orthodontics

BACKGROUND Bone density at the interradicular area plays an important role during orthodontic treatment. In view of this fact, the study was designed to quantitatively evaluate the bone density at the interradicular areas of the alveolar and basal bones of maxilla and mandible by computed tomography. METHODS One hundred and nine computed tomographic images were randomly selected, and bone density was measured in Hounsfield units (HU) with bone mineral density software (Siemens VA20A_SP3A). The sample consisted of 78 males (mean age 29.5 years, range 20 to 40 years) and 31 females (mean age 27.6 years, range 20 to 40 years). Cortical and cancellous bone density was measured at the interradicular areas at the alveolar and basal bone levels of the maxilla and mandible, and the data was subjected to statistical analysis for comparisons. RESULTS The highest cortical bone density was observed between the second premolar and first molar at the alveolar bone level and between the first and second molars at the basal bone level in the maxilla. Maxillary tuberosity showed the least bone density. The density of the cortical bone was greater in the mandible than in the maxilla and showed a progressive increase from the incisor to the retromolar area. The basal bone showed a higher density thanthe alveolar bone. CONCLUSION Different qualities of the bone were found in the anatomic regions studied, which confirms the importance of knowledge of site-specific bone tissue density to correlate with various clinical findings.