Relationship between mandibular condyle and articular eminence cortication with mandibular cortical index on cone-beam CT.

Purpose: Mandibular condyle development can be evaluated with radiographic evaluation of subchondral cortical bone. The aim of this study is to investigate mandibular condyle cortication (MCC), articular eminence cortication (AEC) and mandibular cortical index (MCI) according to age and gender on CBCT, and relationship between each other.

Methods: CBCT scans of 520 patients (312 male and 208 female, age range 7-84) were retrospectively investigated to evaluate MCC, AEC and MCI. MCC and AEC were examined in sagittal section and MCI in panoramic reformatted image. MCC and AEC were classified as Type I, Type II and Type III according to density difference between the cortical bone enclosing condyle and articular eminence. Categorical variables were tested by Chi square.

Results: When MCC, AEC and MCI were compared, a significant relationship was detected (p < 0.05). According to age, there was a significant difference between MCC, MCI and AEC types with each other (p < 0.05). No significant discrepancy was found between gender and MCC, AEC and MCI (p > 0.05).

Conclusions: This study evaluated the distribution of MCC, AEC, MCI according to age and gender and detected that these cortications were correlated. This result may be caused by anatomical proximity bone components and functional stimuli. Knowledge of these cortications can be important for accurate diagnosis of TMJ disorders and may also be helpful for prediction of osteoporotic changes.