Comparison of Soft Tissue Profile between Subgroups of Skeletal Class III Malocclusion

Aim:The aim of this study is to compare the soft tissue profiles of patients with skeletal Class III malocclusions originated from; maxillary retrusion, mandibular protrusion and the combination of maxillary retrusion and mandibular protrusion.Material and Method:Lateral cephalomet-ric radiographs of 66 subjects were divided into three groups according to the Nperp-A and Nperp-Pg variables; Group 1-maxil-lary retrusion (n:23; mean age:13.44 years), Group 2-mandibular protrusion (n:22; mean age:13.31 years), and Group 3-combination of maxillary retrusion and mandibular protrusion (n:21; mean age:13.04 years). Besides the descriptive parameters of Class III subgroups, 13 soft tissue measurements (Gl-Sn, Sn-Me, ULL, St-Me, Sn-LLV, LLV-Me, interlabial distance, upper lip, lower lip, Chin, Gl-Sn/Sn-Me, Sn-St/St-Me and Sn-LLV/LLV-Me) were achieved for evaluating the possible differences between Class III subgroups. The differences between all Class III groups were evaluated by Analysis of Variance (ANO-VA) and Duncan test.Results:Chin measurement (distance between soft tissue pogonion to vertical reference plane) showed the highest value in Group 1 (5.14 ± 2,93) compared with Groups 2 (2.94 ± 2,15) and 3 (3.05 ± 1,98) (p