ABSTRACT
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-L1/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'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.