Assessment of the angle of articular inclination in patients with different skeletal classes according to axiography

The morphology of the articular tubercle of the temporal bone varies in the population and is being formed during the growth and development of the patient. When planning and implementing comprehensive dental treatment, it is necessary to take into account the individual parameters of the articular tubercle inclination in order to achieve a predictable result. The aim of the research was to study the values of the articular inclination angle depending on the subjects’ skeletal class. Materials and methods A clinical cross-sectional retrospective simple centric study in which 265 patients participated: 80 men and 185 women.Clinical studies included filling in the dental formula, intraoral photographs of dentition, palpation of the masticatory muscles and the TMJ area, analysis of the jaws plaster models. Each subject underwent electronic axiography with registration of the lower jaw hinge axis movements. The assessment of the angle of articular inclination (SCI) during translational movements was carried out: protrusion-retrusion, right media intrusion, left media intrusion. The skeletal class was evaluated on the basis of cephalometry data by analyzing teleroentgenograms (TRG) in a lateral projection with markers of the hinge-suborbital axis. Result . In the course of the study, the average values of the articular inclination angle were obtained for protrusion-retrusion, right-hand media intrusion, left-hand media intrusion according to the «Skeletal class» criterion. Differences were found between skeletal classes in terms of SCI.During protrusion – retrusion, the SCI values were significantly higher in the subjects with skeletal class II than in the subjects with skeletal class III. It should be noted that the subjects with II skeletal class with protrusion – retrusion had the highest values of SCI than the subjects with I and III skeletal classes, but no significant differences were found. Conclusions The values of the sagittal condular inclination depend on the skeletal class of jaw relationship. A decrease in the values of sagittal condular inclination is a risk factor for the maxillofacial dysfunction development. The lowest values of sagittal condular inclination were observed in subjects with the III skeletal class which requires special attention when diagnosing and treating this risk group. The value of the sagittal condular inclination should be taken into account when modeling the anatomy of orthopedic structures during prosthetic treatment.