Many people are confused why their teeth discolored even though they brush their teeth every day. There are many reasons causing teeth discoloration and the common ones are as follows:

Superficial extrinsic staining – dietary, smoking or plaque-related discoloration. Superficial extrinsic staining can be removed by a thorough scaling and polishing. Common dietary supplements, for example, tannin, will cause a superficial stain to develop on the exposed surfaces of teeth. Tars and nicotine in cigarette can also cause staining of teeth. Such stains, although superficial, can be quite resistant to routine cleaning and polishing techniques. Whitening toothpastes, containing emulsifiers and titanium dioxide, may remove these stains and appear to whiten the teeth. They are particularly useful for removing dietary stains, tobacco tars and for white maintenance after bleaching.

Tetracycline – Prescribing tetracycline for non-critical infections in patients with developing teeth is now considered to be indefensible. The tetracycline molecule becomes incorporated into developing tissues, changing the color of dentine from which teeth get their inherent color. The degree of yellow to blue-grey discoloration depends on the nature and concentration of tetracycline administered to the patients and the exposure of the tetracycline-containing tooth tissues to ultraviolet light following eruption. Some brown\yellow tetracycline stains are relatively easy to overcome using vital bleaching technique. Blue-grey tetracycline stains often remain resistant to bleaching.

Fluorosis – the intake of excessive amounts of fluorosis during tooth crown formation may result in brown and white speckled mottling of the tooth – fluorosis. Bleaching or removing the superficial layer of enamel with micro abrasion normally eliminates brown mottling. The surrounding white speckled opacity is more difficult to remove but usually responds favorably to vital bleaching.  

Age-related discoloration – as people age their teeth darken or appear darker. This may be a result of enamel wearing, exposing the underlying darker dentine, or the effect of age-related sclerosis if dentine: consequently the tooth appears darker. This apparent change must be balanced against the patient’s age, as the actual color change with age might not be prominent. Equally the tooth color may appear to be natural while lighter teeth would appear unnatural when framed by an older face.