Retrospective Study On Lower Incisor Target Positioning In Skeletal II

This study aims to to explore the relationship between the target position of lower anterior teeth and the mandibular ramus in patients with skeletal Class II The cephalometric of 122 skeletal Class II patients before (T0) and after treatment (T1) were converted into black-and-white silhouette of soft tissue ; 15 raters evaluated the silhouette using a 5-point Likert scale; Pearson correlation analysis was used to preliminarily identify measurement items related to lower incisor position of The patients with lateral profile improved (T1>T0); the good-looking group (T1 ≥ 4 points and ΔT ≥ 2 points) was selected to establish a multiple linear regression equation for predicting the lower incisors' target position. 116 cases with improved lateral profile (52 males, 64 females, mean 26.6 ± 8.3 ages) showed the lower incisors’ target position (T1, ΔT) was significantly correlated with mandibular ramus parameters and vertical skeletal pattern at T0 (p < 0.01);Multiple linear regression analysis indicators in the hyperdivergent good-looking group : IMPA (ΔT) = 91.50 – 3.20 × Go-Ar-FH (T0) + 3.15 × Go-R3-FH (T0) + 1.00 × Wits (T0) (adjusted R² = 0.64) had strong predictive ability and value For skeletal Class II hyperdivergent patients, initial mandibular ramus (Go-Ar-FH) and sigmoid notch (Go-R3-FH) inclinations can predict lower incisor retraction for a high-aesthetic profile. The regression equation is IMPA (ΔT) = 91.50 – 3.20 × Go-Ar-FH (T0) + 3.15 × Go-R3-FH (T0) + 1.00 × Wits (T0) (adjusted R² = 0.64)