Hello,
I am 18 years old and naturally have quite yellow teeth. Otherwise my teeth are healthy, I do not drink coffee or tea, I do not smoke, I regularly visit the dentist and take care of my oral hygiene. Another issue is that I still have one primary tooth, namely a lower canine. I had an X-ray, which showed that there is no permanent tooth underneath, so in fact I have one tooth fewer. My dentist left the primary tooth in place because she said it is completely  healthy. I would like to have my teeth whitened and would like to know whether this is possible in my case at all. Thank you for your answer.
Kind regards,
Marta

Dear Sir/Madam!

Over time teeth change colour toward yellowish, brownish or greyish shades; in short, they become darker. These changes are the result of surface staining (which can be removed) or a deeper colour change that follows changes in the enamel structure. Teeth continue to mature after erupting into the oral cavity, which means that the structure of their hard tissues improves. The enamel crystals become increasingly well organised, and the enamel therefore becomes more translucent to light (similar to glass), making the darker dentine colour more visible. These changes can be masked by whitening, which means that we demineralise the surface enamel layer again, light is scattered more at the surface (rather than passing through the enamel), and the tooth appears whiter. 

Have a nice day!