<unk>  is abnormal tooth color, hue or translucency. External<unk>  is accumulation of stains on the tooth surface. Internal<unk>  is due to absorption of pigment particles into tooth structure. Sometimes there are several different co-existent factors responsible for<unk> .
Tooth discoloration
Skin whitening
Oral pigmentation
Green nails
Blue nails
Muscle atrophy
Tooth loss
Dark skin