It is a microbial disease of the calcified tissues of the teeth,
characterized by demineralization of the inorganic portion
and destruction of the organic substance of the tooth.
Many researches/investigations for more than a hundred years have been done, still, many aspects of the etiology of this disease is obscure and efforts at prevention are only partly successful
A detail of a tooth (to the right = enamel). It is covered by plaque, which consists mainly of bacteria. Plaque is often found close to the gum, in between teeth, in fissures and at other "hidden" sites.
When sugar and other fermentable carbohydrates reaches the bacteria, they form acids which start to dissolve the enamel - an early caries lesion occurs due to loss of Calcium and Phosphates
When sugar consumption has ceased, saliva can wash away sugars and buffer the acids. Calcium and Phosphates can again enter the tooth. The process is strongly facilitated by fluorides
The first indication of tooth decay are white spots on the enamel caused by the loss of calcium.
If the demineralization process outruns the natural remineralisation process, the lesion grows and a cavity is formed.
The bacteria may invade the pulp of the tooth,
causing a consistent tooth pain, especially during the night.
The bacteria may also produce an abscess,
and eventually the tooth may be extracted by the dentist
1.A tooth surface without caries.
2.The first signs of demineralization.
3.The enamel surface has broken down.
4.A filling has been made but the demineralization has not been stopped.
5.The demineralization proceeds and undermines the tooth.
6.The tooth has fractured.