Teeth whitening is generally a safe procedure with occasional sensitivity of teeth as the only side effect. Such sensitivity of teeth may last for 2-3 days and can be easily taken care with medicated toothpastes or gels and a mild over the counter painkiller.
It best works on healthy teeth which have yellow discolouration and are cavity free. Regular teeth whitening procedures are not very effective on grey or brown discolouration of teeth, which are mostly intrinsic in nature. They also don’t work on artificial teeth and fillings.
Teeth Whitening is not advisable for all individuals. It is not done for children. It is avoided during pregnancy and lactation and is not recommended for people with sensitive teeth.