When having a dental veneer put on, the first step in preparing the tooth for a veneer involves removing dental enamel from the tooth surface where the veneer is to be placed. (Much like putting on a fake nail you sand down the nail surface) Even though your tooth will now have less tooth enamel to protect the interior of the tooth from attach by bacteria, when the porcelain veneer is applied to the tooth, it should be adequately protected. The seal formed between veneers and dental enamel or dentin is strong and water tight.

Porcelain veneers has non-stick qualities that make it harder for bacteria and food to adhere to them. Veneers are also resistant to attack by the acids that bacteria secrete, so cavities will not be able to form on the veneers themselves. However, tooth decay can form in the natural tooth enamel that remains behind the veneer. Once decay penetrates into the tooth behind the veneer, the concealing properties of porcelain veneers may prevent you from knowing about it until the damage reaches the tooth nerve, or pulp, leading to infection that may require removal of the tooth or a root canal. If the infection goes unchecked it can sometimes,threaten several teeth and even your jawbone.