Baby 5 months to grow a tooth is normal, the general baby 6 months of age when the first baby teeth eruption, but due to individual development is different, so the time of each baby’s teeth is not exactly the same, the eruption of milk teeth no later than 1 year old is normal, so the baby 5 months to grow a tooth is normal. Usually in 2.5-3 years of age, milk teeth, if 1 year of age after the teeth are not known as delayed eruption of milk teeth, this time you need to find the cause of the disease, the common cause of vitamin D deficiency rickets and hypothyroidism. Vitamin D deficiency is often accompanied by night terrors, poor sleep, excessive sweating, etc. Hypothyroidism is often accompanied by indifference, mental retardation, delayed motor development and low basal metabolism, etc. If your baby has delayed eruption of milk teeth with the above symptoms, you should actively seek medical attention in order to find out the cause of the disease, do not delay the condition.