Role of the oral microflora in health

The mouth contains both distinct mucosal (lips, cheek, tongue, palate) and, uniquely, non-shedding surfaces (teeth) for microbial colonisation. Each surface harbours a diverse but characteristic microflora, the composition and metabolism of which is dictated by the biological properties of each site. The resident oral microflora develops in an orderly manner via waves of microbial succession (both autogenic and allogenic). Pioneer species (many of which are sIgA protease-producing streptococci) colonise saliva-coated surfaces through specific stereo-chemical, adhesin-receptor interactions. The metabolism of these organisms modifies local environmental conditions, facilitating subsequent attachment and growth by later, and more fastidious, colonisers. Eventually, a stable biofilm community develops, that plays an active role in (a) the normal development of the physiology of the habitat, and (b) the innate host defences (colonisation resistance). Thus, when considering treatment options, clinicians should be aware of the need to maintain the beneficial properties of the resident oral microflora.