Correlation analysis between the parameters of the temporomandibular joints and the cervical spine

Objective. To develop a technique for 3D analysis of the upper part of the cervical spine, to study possible correlations with temporomandibular joint (TMJ) parameters in patients with signs of its dysfunction. Material and methods. The data from cone beam computed tomography (CBCT) of the heads of 92 patients who sought treatment for TMJ dysfunction (49 people), comprehensive dental treatment (28 people), and orthognathic surgical treatment (15 people) were analyzed. Patients with signs of TMJ dysfunction were divided into 2 subgroups: 1 — patients with asymmetric narrowing of the articular gap (24 people); 2 — patients with symmetrical narrowing (25 people). The width of the articular gap in the posterior and upper thirds was chosen as the main parameters of the TMJ. To analyze the cervical spine, a technique was developed that determines the rotation of the cervical vertebrae; lateral tilt of the cervical vertebrae; anteroposterior tilt of the cervical vertebrae; distance from the tooth (2nd vertebra) to the atlas (1st vertebra); postural compensation. Results. Contrary to expectations, we found no signs of even a weak relationship between the studied parameters of the TMJ and the cervical spine within the entire group of subjects (the correlation coefficients were 0.17—0.22). However, it was noted that there was a pronounced mutual dependence between violations of the ratios of the elements of the TMJ and the parameters of displacement of the cervical vertebrae in patients of the 1st subgroup. Conclusion. Any methods of fixing the patient’s head can distort its natural position during a CBCT scan, especially its postural balance. Therefore, such an analysis and analysis of the anteroposterior tilt of the vertebrae were intentionally excluded for the study. Nevertheless, the study showed that even with standard methods of conducting CBCT examinations with stops for the patient’s head, it is possible to reliably record and quantify disorders not only of the TMJ, but also of the cervical spine.