The concept of discolouration does not sit well with individuals, especially considering the fact that you brush regularly. Despite all that, you still stand a chance to face the same due to external and internal stains. In most cases, it could be a result of the consumption of coffee, tea and other such habits. Apart from that, if you have suffered trauma or injuries to your teeth, you will be left with an internal stain that can stand to leave your teeth yellow. While external stains arising from the consumption of coffee can be eliminated through brushing, internal stains like trauma do not have a definitive solution. Check out here to know more.