Damage to the hard tissues of the teeth is most common among children. This applies to both temporary and permanent bite. Untimely prevention and treatment of caries leads to the progression of the process in the tissues of the tooth, the occurrence of complications. The aim of the study was to explore the possibility of using various methods of treatment and prevention of caries in deciduous teeth and its complications in children in a dental clinic. For the period from 2020 to 2023, 1659 patients aged 2-6 years old applied to the dental clinic. Each patient was examined, individual training was given to them and their parents in oral hygiene, a treatment plan was drawn up and preventive measures were taken. Recommendations were given on rational nutrition. Sealing was applied in temporary molars within a year after their eruption. After 2 years, 90% of patients did not reveal caries of temporary molars. In children of this age group, the treatment of diseases of the teeth’ hard tissues can be carried out using local anesthesia, under nitrous-nitrogen-oxygen sedation and under general anesthesia. The choice of treatment method will be influenced by the total amount of sanitation and the compliance of the child. In 72% of patients, the intervention was performed under general anesthesia. The use of this method in the clinic makes it possible to treat a certain number of teeth in one visit and work with a cohort of children who are not ready for the usual conditions of admission. The most common pathology treated was caries, accounting for 89% of the children who visited the clinic. Used photopolymer composite filling materials. A complication of caries (inflammation of the pulp or periodontal tissues) was treated in 64% of patients who sought dental care. Each patient underwent an X-ray examination, an orthopantomogram, or targeted images, depending on the age of the child, to decide on the choice of treatment method (tooth preservation or extraction). So, 5.4% of the teeth that needed intervention by a pediatric dentist were subject to extraction. Complicated caries is accompanied by significant destruction of the tooth crown, which requires appropriate treatment approaches. In such cases, standard crowns were more often used, which made it possible to restore the anatomical shape of temporary molars, their function and achieve a long-term treatment effect until the period of physiological changes in the teeth. There are several options for crowns that can be used in pediatric dentistry standard steel crowns (stainless steel crowns), for the restoration of the chewing group of teeth, metal crowns with plastic veneer, for the restoration of the anterior group of teeth and crowns based on a framework of zirconium dioxide, which are universal and biocompatible with periodontal tissues. Admission of children to the dental clinic allows the use of modern methods of diagnosis, anesthesia, treatment, and preventive measures. An important point is the cooperation of a pediatric dentist with the patient's parents, which is the key to obtaining maximum positive results, restore chewing function, aesthetic appearance, achieve an increase in the resistance of hard dental tissues and prevent caries and its further development.

Developmental dental hard tissues disorders are rarely diagnosed both in children and adults, and their treatment is a problem for dentist. Despite the fact that molecular genetics studies allow to discriminate some dentine disorders, pathogenesis of radicular dentin dysplasia is still obscure. Type I dentin dysplasia is characterized by normal or slightly coloured crowns with no roots or only rudimentary roots, reduced pulp space in permanent teeth and incomplete or total obliteration of the pulp chambers, and periapical radiolucent areas or cysts which might result in premature loss of tooth. Fortunately, teeth demonstrate higher resistance to caries than normal teeth do. Dentin dysplasia type II is characterized by yellow, brown, grey, translucent primary teeth with complete pulpal obliteration. Permanent teeth are normal or might be slightly coloured. Roots are normal in size, but pulp chamber has pulp stones. A third type of dentine dysplasia or focal odontoblastic dysplasia has radiographic aspects of the other two types of disease. Also dentine dysplasia type I has subtypes Ia, Ib, Ic and Id. Dentine dysplasia Ia is characterized by complete obliteration of the pulp, disorder of root development, and many periapical radiolucent areas. A single small horizontally oriented and half-moon shaped pulp is presented in case of dentine dysplasia Ib, roots have a few millimetres length and frequent periapical radiolucencies. Dentine dysplasia Ic is characterized by the presence of two horizontal or vertical semicircle-shaped pulpal remnants which surround dentine in pulp chamber. Also teeth have shortened roots and variable periapical radiolucencies. Dentine dysplasia Id is characterized by the distinct pulp chambers with pulp stones in the coronal third of the root canal; periapical radiolucencies are possible as well. Aim of this study was to analyse clinical case of dentine dysplasia in 8,5-year-old boy. A 8,5-year old boy patient with parents came to a dental office due to caries cavity in tooth 62. Shape of tooth crowns was not changed and teeth with no signs of mobility; white lines and spots on teeth are were detected. Based on age, the decision of orthopantomogram was made to evaluate status of primary and permanent teeth. The image showed almost obliterated pulp chamber in both erupted and developing teeth and considerably shortened, blunted and malformed roots without a visible lumen of root canals in primary teeth. Periapical lesions were found about roots of primary molars and follicles of teeth 12 and 14 without caries lesions. Patient's medical history revealed no disturbance in general health. Clinical examination of the patient's mother did not show dental hard tissues disorders, but radiograph examination revealed such disorder in the orthopantomogram. Thus, history, clinical and radiographic findings revealed this case as dentine dysplasia type I subtype 1c inherited from mother. Oral rehabilitation of patients with dentine dysplasia type I require effective prevention and a complex approach. Thus, meticulous oral hygiene measures and dietary instructions, regular check-ups twice a year were established for this patient; orthodontic consultation was recommended. Varnish «Ftoplen-LC» was applied on the permanent teeth 3 times. To prevent early exfoliation, plan of preventive measures was developed included application of fluoride varnish twice a year and fissure sealing in the premolars in 9-10 years and in the second premolars in 12-13 years. Treatment of dentine dysplasia I type that depends on patient age and severity of disease may include also filling of carious teeth, orthodontic, surgical and orthodontic treatment. In this regard, dentist has to know developmental dental hard tissues disorders and select measures to prolong the retention of affected teeth maintaining them as long as possible.