Evaluation of the Effects of Temporomandibular Joint Disc Displacement and Its Progression on Dentocraniofacial Morphology in Symptomatic Patients Using Posteroanterior Cephalometric Analysis

The aim of this study was to evaluate the effects of disc displacement (DD) and its progression on dentocraniofacial morphology in symptomatic patients, and to compare the results with asymptomatic volunteers. Female patients with DD, diagnosed with magnetic resonance imaging (MRI) and posteroanterior cephalometric analysis, were included in this study. Subjects were grouped as follows: control group with bilateral normal disc position (group 1, n=20), unilateral DD with reduction (group 2, n=17), bilateral DD with reduction (group 3, n=32), unilateral DD without reduction (group 4, n=16), and bilateral DD without reduction (group 5, n=19). Thirteen cephalometric variables were measured. A significant increase in the ANS (Anterior nasal spine)-Me (Menton)-MSP (Midsagittal plane) angle in unilateral DD groups and decreases in the Ag (Antegonial notch)-Me dimension on the affected side in all DD groups were observed. Also, the maximum values of the Me-MSP dimension and ANS-Me-MSP angle were observed in group 4. The results of this study showed that the deviation of the menton point toward the disc displacement side causes a mandibular asymmetry. It can be concluded from these results that the presence of DD in female patients affects facial morphology, and its progression makes the differences more significant and remarkable. These results emphasize the importance of early diagnosis and treatment in the management of DD