This final thesis dealt with the topic of fluoride concentration in toothpastes on the Croatian market. Dental caries was initially defined as one of the most widespread diseases of the stomatognathic system. The prevention of caries by proper and regular tooth brushing was then explained, emphasizing the importance of oral hygiene. Then, fluorine was defined as a poisonous gas that has a bright yellow or green color and its metabolism was described. In the continuation of the paper, the concept of fluoridation is described as a method by which fluoride is additionally introduced into the body in order to have a preventive effect on reducing the occurrence of caries and on the resistance of hard dental tissues. There are differences between topical fluoridation and systemic fluoridation. There are various means used for fluoridation, and the basic division is into means for professional use (solutions, varnishes, etc.), gels (for combined use) and means for home use (toothpaste, rinsing liquid, etc.). ). The beginning of the use of toothpaste as well as its usual fluoride concentration is also described. Within the work, research was conducted on sixteen of the most common toothpastes and their fluoride concentrations were analyzed. It was concluded that Plidenta Kids Himalaya Herbals Complete Care toothpastes had the lowest fluoride concentration (500-550 ppm F¯), while Curaprox Kids, Elmex Caries Professional, Lakalut Activ, Parodontax Ultra Clean and Sensodyne Flour + Whitening toothpastes had the highest fluoride concentration (1450 ppm F¯). Research results were compared with foreign research. Analyzed studies confirmed that toothpastes containing 1500 ppm fluoride significantly reduce the proportion of new caries when compared to toothpaste that does not contain fluoride.