Why do we have two teethings?

Have you ever wondered why we have two dentitons? That is, why do not we keep the first dentition (baby teethh) forever? Or why don´t we have three dentitons? This third could be very useful when we have problems with the pieces of the second one.

Teeth are structures formed by two parts, crown and root. The crown is the visible part inside the mouth and its structure consists of enamel (the outer part), dentine and pulp, commonly called nerve. The root is in the bone of the jaws and it is formed by cement (instead of enamel), dentine, and pulp.

All anatomical structures of the body develop during the growth period. This is influenced by genetic factors primarily.

Once formed, teeth don’t grow. Its size is genetically predetermined. When the first teeth appear, they do not increase in size, only the root is developed until it is perfectly formed. Once in place, the tooth size is always the same, normally distributed in the available space in the jawbone, which grows until the individual is fully developed. The jaws of a child are small at the beginning and have little space to accommodate, so these teeth come out so slowly. When the eruption of teeth is complete, there are only twenty and they are smaller than those of the second dentition which are thirty-two.

As the jaws and the rest of the body continue growing, teeth would be a bit ridiculous in the already developed jaws. That's when we start to change the dentiton progressively until we get the final one, which are more and bigger.

* A publication of Dr. Jose Arias Pardiñas, dentist doctor expert in dental implants, periodontics and prosthodontics.