The result showed there were 24 patients with congenitally missing lower incisors, accounting for 5.3% in all orthodontic patients.

• 调查显示下颚先天缺失门齿者共24位，佔所有接受矫正治疗患者的5.；3%25，其中男性7位佔29%25，女性17位佔71%25：缺失2颗下颚门齿者有13位，女性佔12位；