Comparison of chairside microbiological screening systems and conventional selective media in children with and without visible dental caries.

PURPOSE The purpose of this study was to compare the results of commercial chairside microbial tests (CT) and conventional selective media (GS, gold standards) for mutans streptococci (MS) and lactobacilli (LB) using oral specimens from young children with and without visible dental caries. METHODS Using cotton swabs to collect oral microbial specimens from children 10 to 36 months old, microbial counts of CT and GS were compared with caries experience of the subjects. Contamination levels by non-MS or non-LB isolates on CT and GS were also determined. The CT employed were: (1) CRT bacteria for MS and LB; (2) CarioCheck Plus for MS and LB; and (3) Dentocult SM and Mucount for MS. RESULTS All CT and GS for MS represented caries status of the participants (P<.001, Fisher exact test; P<.015 linear regression), whereas only GS for LB showed significant association with caries status (P<.001, Fisher exact test; P<.001, linear regression). Non-MS or non-LB isolates were observed on most media, and CT usually exhibited higher contaminant levels than GS. Dentocult SM and Mucount did not harbor contaminants. CONCLUSIONS Despite contamination, CT and GS for MS and GS for LB exhibited satisfactory outcomes based on cross-sectional caries experience of infants and toddlers.