Children have 20 deciduous teeth. These teeth are also known as the primary, baby, or milk teeth. 

The set of deciduous teeth is also referred to as the primary dentition. These teeth are essential as later they get replaced by permanent teeth. Therefore, the primary teeth help to maintain space for the secondary dentition. 

A lack of a deciduous tooth can cause crooked permanent teeth.

Primary teeth are smaller with smaller roots, but have relatively larger and bigger pulp chambers than the ones of the secondary dentition, but it is not the only difference.

Other differences include the following:

• Deciduous teeth tend to be whiter than permanent ones.

• The crown part is shorter and broader.

• Deciduous teeth have no mamelons.

• Milk teeth have more prominent cervical ridges and a thinner enamel layer.

• The roots of the milk teeth are thinner and more widespread with short or absent root trunks.

Overall, deciduous teeth are very variable in shape and size.

NOTE: in this article, the Universal Tooth Numbering System for primary dentition is used for teeth numbering. Find out what it is and which are the two other most commonly used teeth numbering systems in the article about the dental notation systems!