Tooth discolouration is any change in the hue, translucency or colour of a tooth from the normal white/yellowish-white colour due to a number of reasons.
Etiology:
1) Intrinsic sources
- drugs (tetracycline)
- developmental defects (amelogenosis imperfecta, etc.)
- non vital tooth
- metals
- internal resorption (pink tooth)
- blood borne pigments
- dental fluorosis
- erythroblastosis foetalis
- early jaundice
2) Extrinsic sources
- poor oral hygiene
- plaque
- trauma
- food pigments
- smoking
- tobacco and pan consumption
- chlorhexidine
- stannous fluoride
- metallic salts
- chromogenic bacteria