7 months baby no teeth may be a normal physiological phenomenon, and vitamin D deficiency, late addition of complementary foods have a certain relationship. 1. Physiological phenomenon: most babies start to erupt the first milk teeth at 6 to 8 months, due to the individual development of the child there is a certain difference between the 7-month-old baby did not come out of the teeth is a normal physiological phenomenon. 2. Vitamin D deficiency: Vitamin D deficiency affects calcium absorption and may lead to late eruption of baby teeth. 3. late addition of complementary foods: if the complementary foods are added too late, the child’s gums can not be effectively stimulated, is not conducive to the eruption of milk teeth. 7 months baby teeth have not erupted do not have to worry about, generally no later than 1 year old, if the child after 1 year old teeth still did not erupt, timely child to the hospital, clear cause of the disease after active treatment.