Broken or Knocked-out Teeth

• Broken or Knocked-Out Teeth Overview
• Broken or Knocked-Out Teeth Causes
• Broken or Knocked-Out Teeth Symptoms
• When to Seek Medical Care
• Exams and Tests
• Broken or Knocked-Out Teeth Treatment
• Self-Care at Home
• Medical Treatment
• Next Steps
• Follow-up
• Prevention
• Outlook
• Multimedia
• Synonyms and Keywords
• Authors and Editors

Each individual tooth is composed of calcium and several other organic components. It is divided into 3 layers: enamel, dentin, and pulp—each layer having a specific role.

• Enamel is a hard outer protective coating. It is the hardest substance in the body. A similar substance called cementum provides a protective coating over the root. It differs from dentin by virtue of its porous nature.
  
  
• The vast majority of the tooth is composed of dentin, which is found directly beneath the enamel.
  
  
• The pulp, the innermost layer, contains the blood supply that nourishes the tooth as well as nerve fibers that provide pain and temperature sensation. It also produces the dentin.
  
  

Anatomically, the tooth is made up of the crown and root. The crown is the visible portion you see inside the mouth. The root extends beneath the gum line. The tooth is positioned in a bony socket called the alveolus. It is anchored by a ligament and protected by the gums.

The 20 primary or baby teeth are replaced, beginning at about 6 years, with 32 adult or permanent teeth. Injury to teeth, especially permanent teeth, can be painful and serious.