Introduction. Dental caries (tooth decay) is an infectious and transmissible disease, which produces changes through demineralization in the mineral content of hard mineral tissues and which, under certain conditions, has the capacity to recur as well as to recover through demineralization processes. It is characterized by the demineralization of the inorganic part of the enamel, the destruction of its organic matrix and the softening of the hard dental tissues, with the subsequent cavity defect formation. The relevance of this topic is determined by the increasing incidence of dental caries, its severity, as well as local and general complications produced by dental caries. Also, the changes in tissues determine the type of material, the treatment methods used, and the attitude of the dentist in establishing the diagnosis and treatment plan.  Aim of the study. To study the particularities of medium dental caries manifestation and to select the appropriate filling materials and techniques.   Materials and methods. The study lot comprised 10 patients, of which 3 women and 7 men, aged 18-35 years, who were subjected to examination and treatment. After the examination, the diagnosis of chronic medium caries was established, the process being located on the occlusal and proximal surfaces. In 4 cases, caries Class II was found (according to the Black classification) and in 6 cases - Class I was determined, respectively. To ensure an effective treatment, Seek&Sable Seek Caries Indicator - Ultradent caries detector was used to highlight the hidden areas affected by caries. It was also used Calcimol lc - base liner. As a treatment method, the layered filling technique was used.  Results. According to the study, the efficiency of the treatment was 99.99%, the results being kept until now. Due to the filling material used for the final filling of dental caries - Gradia direct, both the tooth function and aesthetics were restored.  Conclusions. The use of caries detector greatly facilitates the preparation of the carious cavity ensuring total removal of the altered dentin.