What Causes Tooth Staining
There is a direct correlation between tooth colour and age. Over the years, teeth darken as a resut of wear and tear and stain accumulation. Teenagers will likely experience immediate, dramatic results from whitening. In the twenties, as the teeth begin to show a yellow cast, teeth-whitening may require a little more effort. By the forties, the yellow gives way to brown and more maintenance may be called for. By the fifties, the teeth have absorbed a host of stubborn stains which can prove difficult (but not impossible) to remove.
We are all equipped with an inborn tooth colour that ranges from yellow-brownish to greenish-grey, and intensifies over time. Yellow-brown is generally more responsive to whitening than green-grey.
Translucency and thinness:
These are also genetic traits that become more pronouced with age. While all teeth show some translucency, those that are opaque and thick have an advantage: they appear lighter in colour, show more sparkle and are generally more responsive to whitening. Teeth that are thinner and more transparant - most notable the front teeth - have less of the pigment that is necessary for whitening. According to cosmetic dentists, transparancy is the only condition that cannot be corrected by any form of teeth whitening.
The habitual consumption of red wine, coffee, tea, cola, carrots, oranges and other deeply-coloured beverages and foods causes considerable staining over the years. In addition, acidic foods such as citrus fruits and vinegar contribute to enamel erosion. As a result, the surface becomes more transparent and more of the yellow-coloured dentin shows through.
Nicotine leaves brownish deposits which slowly soak into the tooth structure and cause intrinsic discolouration.
Tetracycline usage during tooth formation produces dark grey or brown ribbon stains which are very difficult to remove. Excessive consumption of fluoride causes fluorosis and associated areas of white mottling. Fluorosis will often be enhanced directly after teeth whitening, however, this will return to it's previous state within 1-12 hours.
Most frequently caused by stress, teeth grinding and gnashing can add to micro-cracking in the teeth and can cause the biting edges to darken.
Trauma: Falls and other injuries can produce sizable cracks in the teeth, which collect large amounts of staining and debris.