Dentin can be classified into several types based on its location and formation process:
- Primary Dentin: This is the first-formed dentin and constitutes the bulk of the tooth. It is formed before the tooth erupts and is characterized by its regular tubular structure.
- Secondary Dentin: This type of dentin is formed after tooth eruption and continues to be deposited throughout life. It has a slower formation rate and a slightly different tubular pattern compared to primary dentin.
- Tertiary Dentin: Also known as reparative or reactionary dentin, this type is formed in response to injury or stimuli such as caries or mechanical trauma. It has a more irregular structure and is deposited rapidly to protect the pulp.
