Dimensional Changes of Temporomandibular Joint in Patients Affected by Temporomandibular Disorders: A Combination of Two-Dimensional and Three-Dimensional Evaluation

Introduction: Temporomandibular disorders (TMDs) are frequently associated with degenerative changes involving bony components of temporomandibular joint (TMJ) which may result in morphologic and dimensional changes of them. Aims: This study aimed to evaluate dimensional changes in TMJ in patients affected by TMD using CBCT and a threedimensional (3D) rendering software. Materials and Methods: CBCT images of 68 subjects (19 males and 49 females, age range, 20-50 years) were studied. 40 joints in RDC/TMD (Research Diagnostic Criteria for TMD) II group (disk displacement), 45 joints in RDC/TMD III group (osteoarthritis/osteoarthrosis) and 48 normal joints were included. Variables of length, width, and height of the condyle and slope of articular eminence were measured on CBCT images. Condylar volume was measured using a 3D model of the condyle, reconstructed by 3D rendering software. One-way ANOVA, GLM univariate and Pearson's/Spearman correlation coefficients tests were used for statistical analysis. Results and Discussion: The average condylar volume, width, and height had the highest values in the normal group and the lowest one in RDC/TMD III. The difference of condylar height was statistically significant between RDC/TMD III and the normal group (P= 0.01). Other studied variables were not significantly different among the three groups (P> 0.05). There was a significant correlation between age and condylar volume in RDC/TMDII (P= 0.049). Conclusion: TMD, especially in the early stages, will not lead to significant dimensional changes in the condyle, but in more advanced stages it can lead to a decrease in the height of the condyle.