Colour of teeth
Since the enamel of permanent teeth is slightly transparent, the yellowish colour of the underlying dentine is shown through it. Therefore, permanent teeth will appear slightly yellowish. As we get older, the dentine increasingly grows thicker, and it is normal that our teeth become more yellowish.
Slightly yellowish permanent teeth
The enamel of deciduous teeth is not as transparent as our permanent teeth. That is why deciduous teeth look milky white.
Milky white deciduous teeth
Factors causing tooth discoloration
There are two factors causing tooth discoloration—internal factor and external factor.
External factors causing tooth discoloration
Brown and black stains on the surface of teeth
Habitual smoking or drinking of dark-coloured beverages, such as tea or coffee, result in the food colours being adsorbed onto the tooth surfaces.
The dentist will use:
Green and orange stains at the surface of teeth
Teeth with orange stain
Teeth has not been cleaned thoroughly, and the accumulated dental plaque contained bacteria or fungi that can produce colour and formed green and orange stains.
Dentist will perform scaling to remove accumulated dental plaque and stains.
Teeth after orange stain removal
Brush every morning and before bed at night, and use dental floss to remove dental plaque to keep the teeth white.
Internal factors causing tooth discoloration
Teeth appear to be greyish-blue to brownish-yellow
If there was certain sickness or, if tetracycline (a kind of antibiotics), is taken during the development of teeth, the teeth formed will be brownish-yellow to greyish-blue.
Teeth appear to be greyish-black
The dentist removes the tooth decay, and then puts on a filling.
The pulp becomes necrotic because of tooth trauma or tooth decay, and the tooth will appear greyish-black.
Endodontic treatment must be done to treat the discoloured tooth which has pulp necrosis.
Tooth after root canal therapy
If teeth still appear greyish-black, dentist can treat the discoloured teeth by bleaching, laminate veneer or crown.
Brownish-yellow or white patches at the surface of a tooth