尤某,男,4.5岁。过期产14天剖腹产出体重5.82kg。出生时发现下颌前正中牙槽有两个诞生牙,|I体积如绿豆大小,呈黄色,与乳中切牙相似(两岁时自行脱落)I|切缘刚破龈,以后渐渐萌出,长至米粒大小,呈小牙畸形,并转位90°。　　诊断:下中切牙早萌;嘱家长密切观察,恒牙萌出时随访下颌乳 You Mou, male, 4.5 years old. Caesarean section overdue for 14 days produced 5.82kg of body weight. Birth was found in the middle of the mandibular alveoli have two birth teeth, I volume, such as mung bean size, yellow, similar to the milk in the incisors (two years of their own off) I | cut edge just broken gums, and then gradually eruption, long To the size of rice, was a small tooth deformity, and transposed 90 °. Diagnosis: Lower incisors early adolescent; told parents close observation, eruption of permanent teeth when the jaw milk