The bacterial plaque formed by the bacteria in the mouth can form acid from the mouth residues of sugary and floury foods. These acids dissolve the mineral texture of the tooth and disrupt the enamel layer of the tooth and cause cavities on the teeth.

For the most part, tooth decay is the phenomenon of destruction of enamel, which is the outermost, hard texture of the tooth, dentine beneath it, and occasionally the cementum covering the root surface. It is usually caused by the fact that carbohydrate foods (such as sugar, starch, cola, carbonated beverages, cakes, chocolate) remain on the tooth surface for a long time. Bacteria living in the mouth are fed with these food residues and as a result acid is produced with the aid of microorganisms in the mouth. These acids dissolve the flesh of the mineral and break down hard tissues and cause cavitation.

If teeth become rotten and cavities are formed, they should be treated very urgently. As a treatment protocol; the existing caries tissue is removed from the tooth surface, the cleaned space is disinfected with special medicines and then treated with appropriate material. As filling material; amalgam fillings, composite fillings and porcelain fillings can be used. Amalgam fillings have been very life-saving in the past. But nowadays, they are not preferred due to their aesthetic disadvantages and due to the fact that the radiant fillings are highly developed.