PCR-dipstick DNA chromatography for profiling of a subgroup of caries-associated bacterial species in plaque from healthy coronal surfaces and periodontal pockets.

The onset of plaque-mediated disease, including dental caries and periodontal diseases, is highly associated with compositional change of the resident microflora from the ecological perspective. As specific bacterial profiles have been linked to different disease stages, microbial compositional measurements might therefore have great value for clinical diagnosis. Previously we have reported a dry-reagent strip biosensor-PCR-dipstick DNA chromatography, which utilized molecular recognition of oligonucleotides and biotin-streptavidin, and the optical property of colored microspheres, for semiquantifying a five-membered subgroup of caries-associated bacterial species in supragingival plaque from healthy coronal surfaces of teeth. The present study aimed to evaluate this technique's ability to differentiate microflora by comparing the subset profiles. Sixteen subgingival plaque specimens were pooled from periodontal pockets and analyzed for the composition of Streptococcus mutans, Streptococcus sobrinus, Scardovia wiggsiae, Actinomyces sp. and Veillonella parvula. Detection frequencies, relative abundance of each bacterial species, and the five-membered bacterial profiles were compared between supra- and subgingival groups. The supragingival plaque harbored significantly more of the tested species and higher amount of Actinomyces sp. and V. parvula. In subgingival plaque, the predominance was obscured, since several highly overlapped profiles were found at comparable frequencies. Thus, PCR-dipstick DNA chromatography using the same plaque sample enabled simultaneous profiling of multiple species at species level and facilitated discrimination between anticipated different microflora, making this technique a promising chair-side microbiota profiling method.