小儿出牙为何有早有迟文／梁德有的小儿出生三四个月即长出牙齿，也有的小儿一岁多了还未出牙，这是为什么呢？小儿乳牙正常萌出时间为半岁左右，有少数小儿在出生时或生后２～３个月已有乳牙萌出，这称为“诞生牙”。“诞生牙”常位于下颌中切处，出现的原因有三：（１）... Why children have teeth tooth early / Wende Liang some children born three or four months that grow teeth, and some children more than a year old have not teeth, which is why? Pediatric deciduous teeth normal eruption time is about six months old, a small number of children at birth or 2 to 3 months after birth have had eruptions, which is called “birth tooth.” “Birth tooth” is often located in the mandibular incision, there are three reasons: (1) ...