Assessment of Facial Soft Tissue Dimensions in Adult Patients with Different Sagittal Skeletal Classes using Cone beam Computed Tomography.

INTRODUCTION Few studies utilized cone beam computed tomography (CBCT) to evaluate soft tissue dimensions in malocclusion patients. The aim of this study was to analyze the three-dimensional (3D) soft tissue relationships of adult patients according to their gender and skeletal sagittal class using CBCT Materials and methods: The study sample consisted of 96 CBCT images of patients of both genders; aged 18 to 25 years with a normal vertical skeletal pattern. Patients were segregated into three groups according to their skeletal sagittal class: Class I (2 < ANB < 4), class II (ANB > 4), and class III (ANB < 2). The soft tissue measurements were analyzed in both the sagittal views and frontal volumetric rendered views using 3D-OnDemand software. RESULTS In males, the measurements (U1-stom, nasal width, mouth width) were greater in class I than in class II group. Lower lip thickness was greater in class I than in class III group (p < 0.05). In females, both labiomental fold thickness and upper lip height measurements showed greater mean values in class II than in class I group. In contrast, lower lip height was greater in class I than in class III group. Ls-Pr, U1-stom, and face width at Cheilion revealed greater values in class III patients than in class II patients. On the other hand, the lower lip thickness, upper lip height, and lower lip height measurements showed greater values in class II than in class III group (p < 0.05). Soft tissue thicknesses and measurements were greater in males than in females. However, statistically significant differences between the two sexes were not detected for all of the variables measured in each skeletal class. CONCLUSION The current study indicates the presence of differences in soft tissue thicknesses and facial soft tissue dimensions among skeletal classes and between the two sexes. CLINICAL SIGNIFICANCE Cone beam computed tomography imaging is a very valuable tool to analyze 3D soft tissue characteristics of patients with different skeletal patterns of malocclusion.