K00.9: Disorder of tooth development, unspecified

Every tooth consists of 3 sections: the crown, the tooth neck (cervix) and the tooth root. The crown is the visible part of the tooth. The tooth neck is covered by the gums. The tooth root keeps the tooth in the jawbone. Every tooth has a hollow interior. Connective tissue such as nerves and blood vessels is found inside a tooth. Through its interior, a tooth is formed and sustained. The outside of a tooth is protected by hard layers. The hard outer layers include the enamel and the dentin. Other layers are the cementum and the root.

Tooth development begins in the womb. A tooth development disorder can affect every element of a tooth. If elements are under-developed or absent, a tooth may look different. For example, the shape or color of the tooth may be different. The size of a tooth can also be abnormal. Milk teeth and adult teeth can both be affected.

Changes to genetic information may be a cause of teeth developing differently. Damage to milk teeth can also cause the subsequent adult tooth to be different. Disorders or certain drugs can also affect tooth development.