上下颌第二磨牙先天缺失比较少见,我院诊治1例双侧下颌第二磨牙,右侧上颌尖牙、第二前磨牙、第二磨牙先天缺失病例,报告如下:患者,女,33岁,因右上前牙松动十年余就诊。检查:全口混合牙列,53,55滞留。53松动Ⅲ°;55松动Ⅲ°;17、37、47缺失,26、36、46釉质发育不全;12、22过小牙。毛发,指 Upper and lower jaw of the second molars congenital absence is relatively rare, our hospital diagnosis and treatment of a case of bilateral mandibular second molar, the right maxillary canine, the second premolar, the second molars congenital absence of cases, the report is as follows: patients, female, 33 years old, Due to the upper right anterior loosening more than ten years of treatment. Check: full mixed dentition, 53,55 stranded. 53 loose Ⅲ °; 55 loose Ⅲ °; 17,37,47 missing, 26,36,46 enamel hypoplasia; 12,22 too small teeth. Hair, means