Investigation of plaque flora of human carious teeth using a microsampling technique

Abstract

54 punch samples of enamel with adherent plaque, each representing approximately 0.2mm 2 of the tooth surface area, were removed from 12 primary and 23 permanent, freshly-extracted teeth. The areas sampled were occlusal and smooth-surface lesions and sound enamel surfaces. Bacteriological examination of the homogenized samples, using selective and nonselective media, incubated aerobically and anaerobically, led to the isolation of a range of microorganisms. The frequency of isolation of some known cariogenic species of lactobacilli, streptococci and actinomyces at the different sample sites was compared. The results show that this accurate sampling of a microscopically-identified area of the tooth surface can demonstrate differences in the plaque flora of sound and carious enamel, of different types of lesion in the same dentition, and of similar lesions in primary or permanent teeth.