Well, you need to know that your teeth turns yellow due to a number of reasons and forms a greyish shade due to food stain. However, one of the major factors that contribute to teeth turning yellow is heavy cigarette smoking. Nicotine leaves yellowish or a brown layered stain on the surface of your teeth and this can be removed by undergoing a tooth cleansing. Some people believe that chewing teeth whitening gum or mouth fresheners will protect your teeth, but you may end up inviting more health problems if used in excess.

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