生长发育期骨性Ⅱ^1类错[牙合]低角型患者颅面部的特征

Morphological features of brachyfaeial type patients in growing period with class Ⅱ^1 malocclusions

目的通过对生长发育期骨性Ⅱ^1类错[牙合]低角型患者的32项X线头影测量值与正常[牙合]进行比较分析，旨在研究此类患者的颅面软硬组织的变化和特征。方法选择生长发育期骨性Ⅱ^1类错[牙合]低角型患者60例，治疗前摄X线头颅定位侧位片（磨牙为远中关系，角ANB〉5°，下颌平面角Go-Gn-SN〈28°），年龄11～13岁，男、女各半。结果SNA角、ANB角、上颌切牙倾斜度（U1-NA）、下颌切牙倾斜度（L1-GoGn）、腭平面角（PP—FH）、上下齿槽座点到功能性[牙合]平面距离（Wits值）、后下面高（PLFH）、上下中切牙覆[牙合]程度（U1-L1／N-Me）、下中切牙高度（Me-L1／N—Me）均明显增加；下颌平面角（Go-Gn-SN）、[牙合]平面与下颌平面角（OP—MP）、[牙合]平面与眶耳平面角（OP-FH）、上下中切牙交角（U1-L1）、前下面高（ANS-Me）、前下面高／前全面高（ANS-Me／N-Me）、前下面高／后下面高（ALFH／PLFH）、下颌基骨长（B＇-J’）均明显减少；软组织侧貌唇部突度（NB-Pg＇-Ls）、颏唇沟深（Si-Pg＇-Ls）、下唇厚度（Li-L1）明显增加。结论骨性Ⅱ^1类错[牙合]低角型患者具有前下面高减少、后下面高增加、腭平面顺时针旋转，[牙合]平面、下颌平面逆时针旋转，深覆[牙合]加重；软组织呈现出上唇突出、下唇卷缩、颏部后缩的突面型。

Objective To evaluate the characteristics of brachyfacial types in adolescents with class II^1 division 1 malocclusions by comparing with normal patterns. Methods 32 parameters were evaluated in pretreatment lateral cephalograms of 60 brachyfacial type adolescents, including 30 boys and 30 girls, aged from 11 to 13 years, with class Ⅱ^1 division 1 malocclusions （distal moral relationship, ANB〉5°, Go-Gn-SN〉28°）. Results There was a remarkable increase in SNA, ANB, upper incisor inclination （U1-NA）, U1-L1/N-Me and Me-IA/N-Me, so was lip protrusion of soft tissue facial profile （NB-Pg＇- Ls）; the lower sulcus depth （Si-Pg＇-Ls） and the lower lip thickness （Li-L1）. Mandibular plane （Go-Gn- SN）, OP-MP, OP-FH, U1-L1, anterior lower facial height （ANS-Me）, anterior lower facial height/anterior facial height （ANS-Me/N-Me）, anterior lower facial height / posterior lower facial height （ALFH/PLFH） and mandibular length （B＇-J＇） were significantly decreased. Conslusions Brachyfacial type in adolescents with class II^1 division 1 malocclusions is characterized by decreased anterior lower facial height, increased posterior lower facial height, clockwise rotation of the palatal plane, anticlockwise rotation of the occlusion plane and mandibular plane, deepen overbite, soft tissue protrusive profiles with upper lip protrusion, crimpled lower lip and retracted chin.