Mutans streptococci and their specific oral target. New implications to prevent dental caries?

Abstract

Over the past 25 years collection and analysis of clinical, dietary and microbiological data have led to the conclusion that caries is a bacterial infection, initiated by mutans streptococci which can be transmitted within a family by saliva. Bacteria attach themselves selectively to various oral surfaces. In order to inhabit the mouth mutans streptococci require the presence of teeth. The targets of the odontopathogens (tooth hard substances and gingival sulcus) appear into the oral cavity on a "peculiar" way: these surfaces and tissues are not exposed to bacterial colonization from birth as skin and mucosa. Teething starts 8 +/- 2 months after birth at which age the infant's antibody-dependent defence system is physiologically weak. Teeth erupt slowly during the night, at a period of least intraoral activity. Theoretically, streptococcal colonization can begin as soon as a few mm2 of incisal edges of primary teeth become visible. The earlier the establishment of mutans streptococci in the plaque of the primary teeth, the earlier and more extensive is the caries development. These aspects might open new possibilities for the prevention of the dental diseases, provided that means are found by which the primary colonization can be hindered or postponed.