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Column originally published Dec 1, 1999

Significant Delay In Tooth Eruption In Baby Is A Concern

Question: My 18-month-old son has only two teeth, which he got 6 months ago. There is no sign of any more teeth coming. Does this sound okay to you? I had gestational diabetes during my pregnancy, and I am an “older” mother, having him by C-section at 39.

Answer:

Before answering your question, let me briefly explain about the development of teeth in children to make it easier for you to understand.

Every child has twenty baby teeth (also called primary teeth) and 32 permanent teeth. All primary teeth started developing well before birth. In the great majority, the first teeth to come out are the two front teeth (called central incisors) in the lower jaw. They usually start to appear around 5 to 7 months of age. After this, one or two teeth will appear almost every one to two months. The last baby molars usually erupt between 20 to 30 months of age.

Some of the permanent teeth start developing within several months after birth, although the first ones will not appear until 7 or 8 years of age. In most children, the baby teeth will fall off one at a time, when the permanent teeth are coming through. In this way, the relative positions of the teeth are maintained. The last molars, also called “wisdom teeth,” often erupt in late teens or early twenties.

Just like any part of our body, there are variations in development and eruption of teeth. About one in 2,000 babies are born with one or two teeth already present. These are called natal teeth, and they are usually not anchored well in the gum, with little root support. Presence of natal teeth in the newborns can affect nursing.

For most children, the first signs of teething often happen around 3 to 4 months of age, when parents notice more drooling, chewing, and sometimes irritability. There may be slight fever present. Teething cannot cause high fever. Instead, it is a sign of viral or bacterial infection.

Some children can have delay in eruption for several months. However, a delay of 6 months is certainly longer than average. The first two teeth, which are usually the central incisors in the lower jaw, normally erupt around 5 to 7 months of age. These are followed by the central incisors in the upper jaw, at 6 to 8 months. By 18 months of age, many children can have as many as 16 teeth, including the first molars.

Your son did not have any teeth until 12 months of age, which is much later than most children. After another 6 months, there is still no sign of another tooth. I would be quite concerned. There are a number of medical conditions that can affect the development of teeth, including abnormalities of the hormonal system and congenital problems. I suggest that you take your son to your family doctor for thorough examination.

Finally, children may be born with missing tooth buds. This can be confirmed by special X-ray of the jaws that is available at most dental clinics. Consultation with a dentist may become your next step. Good luck.