患儿女，３岁。半年前，左侧一下前牙出现松动，近两月，该牙松动度明显增加，影响咀嚼进食。１月前，无意中发现右侧一下前牙牙冠呈浅红色而就诊。虽无明确的颌面部外伤史，但家长并不否认幼儿牙齿的外伤。检查：患儿神志清，发育正常，行走自如。面部对称，开口正常。８２牙 Children with children, 3 years old. Six months ago, the left front teeth appear loose, the past two months, the tooth mobility significantly increased, affecting chewing eating. A month ago, inadvertently found the right front tooth crown was light red and treatment. Although there is no clear history of maxillofacial trauma, but parents do not deny the traumatic teeth of young children. Check: children with clear consciousness, normal development, walking freely. Facial symmetry, normal opening. 82 teeth