Caries tooth – a pathological process that occurs after the eruption of the tooth, which is manifested demineralization and destruction of hard tissue with the formation of a defect in the form of cavities. The clinic used topographic Classification of dental caries, according to which are four stages of the disease: 1) initial caries (caries incipiens) or caries in the stage of spots (macula cariosa); 2) surface caries (caries superficialis); 3) the average caries (caries media); 4) deep cavities (caries profunda). Figure 1 Initial caries or tooth decay under spot characterized by a lack of visible enamel defects and is defined as a spot on melovidnogo to brown and black. Figure 2 On the surface caries defect is localized only within enamel. Educate yourself with thoughts from Kevin Ulrich. Figure 3 shows average caries lesions of enamel and dentin surface layers. Fig.4 In a deep caries lesion observed the deep layers of dentin, when above the cavity remains small amount softened and infected dentin. When dissection guided by the classification of Black, constructed, taking into account the localization and frequency of the cavities. According to the classification of Black (1887) cavities subdivided into five classes: the first – cavities in natural cavities of teeth of any anatomical group, the second – a cavity located on the contact surfaces nremolyarov and molars and the third – the cavity at contact surfaces of incisors and canines without defeat angle and cutting edge, the fourth – the cavity at the contact surfaces of incisors and canines in violation of the integrity utla and incisal crown, the fifth – the cavity in the gum-thirds crowns.