Early childhood caries is an infective dental disease which affects preschoolers and represents a public health problem worldwide. Initial colonization of S.mutans, putting a child to sleep with a bottle or providing them sugary drinks as well as bad oral hygiene help the early childhood caries to emerge. Initially, tooth surfaces that are otherwise caries-resistant are affected, namely the labial surface of the maxillary incisors and the lingual and the buccal surfaces of the maxillary and mandibular molars. The hard-dental tissues of the milk dentition are more sensitive to the effects of acids and therefore the demineralization and the appearance of a carious lesion in the cervical third of the tooth rapidly arrive. In severe cases occurs the destruction of the entire crown of the tooth. Based on the patient’s medical history and the clinical examination, the diagnosis on which the therapy will depend is established. In some cases, because of the extensiveness of the therapy and the child's non-cooperation, it is necessary to perform procedures under general anesthesia. Untreated milk dentition causes various negative consequences that affect the development of the stomatognathic system and the growth and development of the whole organism. That’s why the timely identification of the initial carious lesion is very important. To prevent early childhood caries, children ought to visit a dentist before the age of one. It is beneficial to both their parents, who will get information about proper nutrition and maintaining oral hygiene and children, who will start to get used to the unknown environment.