Probiotics are defined as live microorganisms that beneficially affect the host. Probiotic bacteria have been used therapeutically for years to target gastrointestinal disease by rebalancing the complex microflora. Besides the gastrointestinal tract also the oral cavity is highly colonized by bacteria and many different bacterial species are part of the microbiota in the mouth, as it offers ideal conditions for bacteria with a stable temperature, moist surface with a relatively stable pH and regular supply of nutrients. By disturbing the balance of microorganisms in the oral cavity or by extensive accumulation of plaque, the ratio of pathogenic organisms can increase and lead to oral health problems. Probiotic bacteria, like lactobacilli, are a promising treatment strategy for oral diseases with a microbiological aetiology. Those include plaqueassociated diseases like dental caries, which is an infectious disease with microbial processes eroding and destroying the hard dental tissue or inflammation of periodontal tissue, namely gingivitis and the more severe periodontitis. Moreover, endodontic infections, and even fungal, viral and acute bacterial infections could be treated by a probiotic therapy. The interest of probiotics in the field of oral health is growing, although it is still in its infancy. The present review adresses criteria for the selection of probiotic lactobacilli strains. It encompasses existing evidence on the use of lactobacilli for caries, halitosis and candidiasis, as well as for periodontal disease like Gingivitis and periodontitis.