Supplementary Material for: Oral Lactobacilli Related to Caries Status of Children with Primary Dentition

Oral lactobacilli are members of a group of bacteria implicated in caries progression, although information regarding their transmission, colonization, and caries-associated species is not well established. This study isolated oral lactobacilli from a group of children with primary dentition for determination of <i>Lactobacillus</i> prevalence, detection of <i>Streptococcus mutans</i>, a major pathogen of caries initiation, and dental caries status of the children. Species of <i>Lactobacillus</i> isolates were determined from examination of 16S rDNA sequences. Subsequently, the most prevalent species was evaluated for involvement in caries status, and binding ability to type I collagen of all <i>Lactobacillus</i> isolates was determined in association with caries status. Multilocus sequence typing (MLST) of eleven loci was carried out to study strains of the predominant <i>Lactobacillus</i> sp. The detection of oral lactobacilli together with <i>S. mutans</i> was significantly associated with the highest dental caries indices, but there was no involvement of collagen-binding properties of <i>Lactobacillus</i> isolates in caries status. <i>Lactobacillus fermentum</i> was the most prevalent, and its presence was related to high scores of caries indices. MLST analysis of <i>L. fermentum</i> population could not specify a particular clone associated with caries status, but revealed sharing of identical <i>L. fermentum</i> strains among children in the same classrooms. Taken together, the data contributed useful information on the role of oral lactobacilli, in particular <i>L. fermentum</i> in dental caries.