Many of us have discoloured teeth. Very often it's caused by diet. Too much coffee/tea, too much red wine – smoking is also a significant factor in staining our teeth. Sometimes, a lack of knowledge about general oral hygiene can also be a cause. If we want to keep our teeth looking as white as possible, it is important that we follow our dentists advice on how best to clean our teeth and look after our gums. The problem is that not everybody is as well disciplined about looking after our teeth as we should be.