Trabecular bone ratio of the mandibular condyle according to the presence of teeth: a micro-CT study

During mastication, mechanical pressure from the dentition is transmitted to the trabecular bone of the mandible. The occlusal forces, which could thus affect condylar growth, vary with tooth loss, age, and sex. The trabecular bone of the mandibular condyle is denser in dentate subjects than in edentate subjects. However, since the different tooth groups (incisor, premolar, and molar) have different functions, they could exert different effects on the mandibular condyle. The aim of this study was to elucidate the bone quantity of the Korean mandibular condyle according to the presence of teeth using micro-computed tomography (micro-CT), thereby clarifying the influences of tooth presence on the condylar microstructure. Thirty-one sides were scanned and reconstructed into a 3D structure using a micro-CT system. The specimen was sectioned vertically, passing through the medial and lateral poles of the mandibular condyle (P0) to enable measurement of the trabecular bone ratio. Likewise, three additional images, parallel with P0, were acquired. Mean and standard deviation values were calculated, and the t test, one-way ANOVA and post hoc analysis were performed to examine the differences among each group, classified according to the presence of teeth and according to sex. The density of the trabecular bone of the mandibular condyle was significantly associated with the presence of the molars, but not the incisors or premolars. There were significant differences between sexes. The present study has provided data regarding the bone quantity of the trabeculae of the mandibular condyle according to the presence or absence of teeth.