Symphysis Morphology And The Inclination Of Lower Incisor In Xinjiang Uygur Adults With Skeletal Class Ⅰand Ⅱ Malocclusion

Objective: To compare symphysis morphology and inclination of lower incisor ofxinjiang uygur adult patients with skeletal class Ⅰ and class Ⅱ different skeletal p attern.Method: Choose 2017-2020 in xinjiang medical university affiliated oral or thodontics,division of uighurs in adult patients with 180 cases,aged 18 to 30,th e average age24.42 years,including 90 patients with skeletal class Ⅰ(0°≤ANB≤4.7°)and 90 patients with skeletal class Ⅱ(ANB > 4.7 °),according to the mandibular plane angle(SN-MP)and anterior and posterior facidal height ratio(S-Go/N-Me),skeletal class Ⅰ and class Ⅱ patients were divided into 6 group s:brachyfacial group(30 cases)、mesofacial group(30 cases)、dolichofacial group(30cases).The lateral cephalometric images under the natural cephalometric position w ere taken,and the relevant indexes of mandibular association were analyzed by fi xed-point measurement with Winceph 8.0 software,and the relevant data were ana lyzed by SPSS 22.0 software.Results:skeletal class Ⅰ and class Ⅱ groups are chara cterized by the height of symphysis,height/width ratio(H/A),Holdaway rate arepositively correlated with the mandibular plane angle,the inclination of the incis ed teeth(IMPA),the width of the symphysis,chin angle are negatively correlatedwith mandibular plane angle,statistically significant difference(P < 0.05).The IM PA of patients with different Sagittal facial type: skeletal class Ⅰ > skeletal classⅡ,statistically significant differences,There were no significant differences in mand ibular symphysis height,width,height/width ratio(H/A),chin angle and Holdaway(P > 0.05).There was A significant positive correlation between chin angle and the inclination of lower incisors(P < 0.05).Conclusion: There was a strong correl ation between the shape of mandibular symphysis and the vertical facial pattern,b ut a weak correlation between the sagittal facial pattern,and the chin angle of m andibular symphysis and the inclination of lower incisor(IMPA).