Assessing soft tissue characteristics of facial asymmetry

Abstract

Background: Many human body parts undergo development with bilateral symmetry. This implies that the right and left sides can be divided into identical mirror images. However, due to biological factors inherent to processes of development as well as environmental disturbances, perfect bilateral symmetry is rarely found. Aim: Determine soft tissue characteristics affect the subjective assessment of facial asymmetry. Materials and Methods: The collected data and materials were processed using cross sectional study model. 77 participants were selected based on the criteria of study, 5 orthodontist assessed subjectively facial asymmetry used a 100mm visual analog scale. The scale was divided into 3 equal groups. Group 1 included patients with the least facial asymmetry, group 2 included patients with moderate facial asymmetry and group 3 included patients with the most facial asymmetry. We used 11 landmarks, 10 lines to measured 9 angle and 2 line measurement. Results: In subjective assessment of facial asymmetry, 52% had normal and mild asymmetry, 29% moderate asymmetry, 19% severe asymmetry. Lip canting (p<0.005), otobasion canting (p<0.029), nose deviation (0.004), chin deviation (0.001), ramus inclination difference (p<0.043) had significant differences between the groups. The measurement values increased from group 1 to group 3 while 5 measurements compared with between groups subjectively assessed facial asymmetry. Conclusion: We concluded that lip canting, otobasion canting, nose deviation, chin deviation, ramus inclination difference affect subjective assessment of facial asymmetry.