The dynamic development of knowledge in the field of probiotics was commenced at the beginning of the 20th century. Since then, many ways of their possible usage in medicine have been established. In accordance with the WHO, probiotics are live microorganisms, which if applied in adequate amounts may benefit the host. Among probiotics, fungi and bacteria are distinguished, and mechanisms of action of these organisms in the oral cavity and gut are parallel. Application in dentistry, in prophylaxis and treatment of oral diseases is still not well known. Most commonly, Lactobacillus reuteri, Lactobacillus rhamnosus GG and Bifidobacterium are applied. The aim of the study was to collect and systematize the latest information about probiotics and their role in pathomechanisms of dental caries, gingivitis and periodontitis, candidiasis, and malodour. Based on the analyzed literature, it can be concluded that mechanisms of cariogenic pathogen inhibition using probiotics are still not well understood. The new research trend is based on application of probiotics which can naturally displace cariogenic bacteria in the oral cavity and influence oral health in adults and children. The results of studies also confirmed the beneficial role of probiotics in reduction of the bacterial population in periodontitis and halitosis. Long-term observation and a properly designed study protocol will allow us to answer many questions concerning substitution of one strain of bacteria by another.