Epidemiological studies are therefore needed on the distribution learn more and virulence potential of these yeasts in different population groups, addressing risk factors and developing strategies for the control and prevention of infections. 27, 30 and 31 Yeasts are found colonizing various sites in the oral cavity (lingual, palate, tonsils, mucosa of the lips and cheeks,

caries, periodontic and endodontic lesions). 32, 33, 34 and 35 Siqueira and Rôças 35 found C. albicans species associated with bacteria in teeth with periodontal pockets around areas of root exposure. For those authors, resistance to intra canal drugs, and the ability of these yeasts to colonize and invade the dentine tubules, may explain the presence of yeast in persistent endodontic infections. The use of a prosthesis is another factor that may favour colonization of the oral cavity by Candida spp. 36 with a report indicating that the microbiota between a prosthesis and palate mucosa has a composition similar to dental biofilm, except for a greater proportion of Candida species, a fact related to the development of candidiasis on the mucosa of the palate. Kleinegger et al.37 concluded that a number of natural barriers

existed in the mucosal surfaces and body fluids; preventing the colonization in healthy individuals. Protease Inhibitor Library concentration These barriers are more or less effective, depending on factors related to age, gender, smoking, diet, drugs and the host immune status. This explains the fact that not all individuals harbour Candida spp. Saliva helps maintain oral health, provides a buffering capacity and provides lubrication of the mucous membranes; therefore, qualitative and quantitative changes in saliva inevitably affect the physiology, defence mechanisms and microbial ecology of the mouth.38 Lactoferrin and lysozyme are two proteins in the innate immune response present in saliva and exert an antifungal modulating effect on the implantation of species of Candida in the oral cavity. 39 Other important proteins in human saliva that have a cytotoxic action on bacteria and fungi are the histatins, estaterins, lactoperoxidase

and calprotectin. 37 According to Lin et al., 40 when there is a decrease when the concentration of salivary histatins, dysfunction much of these proteins occurs and candidiasis tends to manifest. HIV-infected individuals show a reduction in salivary flow and an anti Candida activity of saliva and are often suffering from oropharyngeal candidiasis. For those authors, the saliva contained mucins and aggregated IgA, histatin, lactoferrin and lysozyme, which remained focused on mucosal surfaces and exerted an antimicrobial effect. 41C albicans is able to connect to several species of streptococci (S. oralis, S. sanguinis, S. gordonii, and Fusobacterium) through recognition receptor polysaccharides in the bacterial cell surface. F.