Tooth discoloration
![Cross-sectional diagram of a molar tooth. 1: crown, 2: root, 3: enamel, 4: dentin and dentin tubules, 5: pulp chamber, 6: blood vessels and nerve within root canal, 7: periodontal ligament, 8: apex and periapical region, 9: alveolar bone](/Images/godic/202502/16/Cross_sections_of_teeth_labels0354.png")
![VITA classical A1-D4 shade guide arranged according to value](/Images/godic/202502/16/VITA_shade_guide0354.jpg")
![VITA classical A1-D4 shade guide arranged according to chroma; A: red-brown, B: red-yellow, C: grey, D: red-grey](/Images/godic/202502/16/VITA_shade_guide20354.jpg")
![The stained teeth of a regular betel chewer in Burma](/Images/godic/202502/16/Betel0354.jpg")
Tooth discoloration (also termed tooth staining) is abnormal tooth color, hue or translucency. External discoloration is accumulation of stains on the tooth surface. Internal discoloration is due to absorption of pigment particles into tooth structure. Sometimes there are several different co-existent factors responsible for discoloration.