Three-dimensional Quantitative Analysis of the Bone Density of Mandibular Condyle in Dentulous and Edentulous Jaws: An In Vivo Study

Studies have reported that masticatory function and occlusal force are low in edentulous patients, which brings about a change in the density, thickness, and alignment of bony trabeculae. However, studies that have quantitatively measured the differential cortical and medullary bone densities of the mandibular condyle in vivo remain rare. This study determined and compared the cortical and medullary bone density of the mandibular condyle in dentulous and edentulous jaws, using multidetector computed tomography (CT). Forty mandibular condyles with no clinical signs of temporomandibular disorders were investigated in 2 groups with 10 subjects (aged 50-80 yr) in each group (group I: dentulous subjects with maintained occlusion; group II: completely edentulous patients) with multidetector CT. The density of condylar cortical and medullary bone was determined by using bone density analysis algorithms available within the proprietary software. Data were analyzed statistically with the 1-way analysis of variance test (p < 0.05). The mean cortical bone density of the right and left condyles of group I was 686.11 ± 102.78 Hounsfield unit (HU) and 775.91 ± 89.62 HU, respectively and that of group II was 531.33 ± 289.73 HU and 648.53 ± 294.39 HU, respectively. The mean medullary bone density of the right and left condyles was maximum in group I subjects (429.69 ± 102.62 HU and 486.62 ± 108.60 HU, respectively) than in group II subjects (214.89 ± 104.37 HU and 205.36 ± 90.91 HU, respectively) with a statistically significant decrease in the mean scores (p < 0.001). Within the limitations of this study, it can be concluded that the cortical and medullary densities of the mandibular condyle are more in dentulous than the edentulous jaws.