This post is also available in: English Slovenščina (Slovenian)

The mouth is the door through which a variety of microorganisms can enter the ali­mentary and respiratory systems. Normally, infection of the oral cavity is prevented by the mucosal barrier and continuous desquamation of oral epithelium, as well as by tooth brushing and other forms of mouth cleaning. Immunologic defense mechanisms, particularly secretory IgA antibodies, seem to prevent microorganisms from adhering to mucosal and dental surfaces.