Morphometric evaluation of patients with temporomandibular hypomobility due to coronoid process hyperplasia using cone beam computed tomography

Mandibular hypomobility is a condition in which jaw movements are limited for some reasons. One of the causes of mandibular hypomobility is coronoid process hyperplasia (CPH). The aim of this study is to evaluate the relationship of the coronoid processes (CP) of patients diagnosed with CPH with other anatomical structures and to examine to what extent and how it affects mandibular hypomobility. To compare the differences in CP anatomy and measurements to be made in patients diagnosed with CPH with healthy individuals. Cone Beam Computed Tomography (CBCT) images of 10 patients diagnosed with mandibular hypomobility due to bilateral CPH and 30 healthy individuals were examined in the study. In CBCT sections, condyle length (H1), CP length (H2), CP length above the zygomatic arch (H3), ramus length (H4), horizontal distance between CP and zygomatic arch (D), angle between CP and mandibular plane (MD) was measured. The data were evaluated statistically. In the study group, a statistically significant difference was found between the average values of the coronoid process and mandibular plane (Cr-MD) angle according to the sides (right-left) (p = 0.031). A statistically significant difference was observed in the H2, H2/H1, H3, H3/H2, H2/H4, D distance values between the study group and the control group (p<0.001). Additionally, it was determined that there was a statistically significant difference in CP and MD angle values between the groups (p = 0.003). Our study has shown that, in addition to the CP length, values such as the H2/H1 ratio, CP and MD angle, D distance, and H3 are factors that affect mouth opening limitation. New studies with larger samples are needed to support the results of this study.