title: Bacterial profiles of root caries in elderly patients.
abstract: Culture-based studies have shown that Streptococcus mutans and lactobacilli are associated with root caries (RC). The purpose of the present study was to assess the bacterial diversity of RC in elderly patients by use of culture-independent molecular techniques and to determine the associations of specific bacterial species or bacterial communities with healthy and carious roots. Plaque was collected from root surfaces of 10 control subjects with no RC and from 11 subjects with RC. The bacterial 16S rRNA genes from extracted DNA were PCR amplified, cloned, and sequenced to determine species identity. From a total of 3,544 clones, 245 predominant species or phylotypes were observed, representing eight bacterial phyla. The majority (54%) of the species detected have not yet been cultivated. Species of Selenomonas and Veillonella were common in all samples. The healthy microbiota included Fusobacterium nucleatum subsp. polymorphum, Leptotrichia spp., Selenomonas noxia, Streptococcus cristatus, and Kingella oralis. Lactobacilli were absent, S. mutans was present in one, and Actinomyces spp. were present in 50% of the controls. In contrast, the microbiota of the RC subjects was dominated by Actinomyces spp., lactobacilli, S. mutans, Enterococcus faecalis, Selenomonas sp. clone CS002, Atopobium and Olsenella spp., Prevotella multisaccharivorax, Pseudoramibacter alactolyticus, and Propionibacterium sp. strain FMA5. The bacterial profiles of RC showed considerable subject-to-subject variation, indicating that the microbial communities are more complex than previously presumed. The data suggest that putative etiological agents of RC include not only S. mutans, lactobacilli, and Actinomyces but also species of Atopobium, Olsenella, Pseudoramibacter, Propionibacterium, and Selenomonas.
authors.affiliation: Institute of Oral Biology, Faculty of Dentistry, University of Oslo, PO Box 1052 Blindern, 0316 Oslo, Norway. doritap@odont.uio.no.
authors.forename: Dorita
authors.initials: D
authors.lastname: Preza
authors.forename: Ingar
authors.initials: I
authors.lastname: Olsen
authors.forename: Jørn A
authors.initials: JA
authors.lastname: Aas
authors.forename: Tiril
authors.initials: T
authors.lastname: Willumsen
authors.forename: Bjørn
authors.initials: B
authors.lastname: Grinde
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Paster
mesh_terms: D000369:Aged, 80 and over; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000032:analysis; D003773:Dental Plaque / Q000382:microbiology; D005260:Female; D020459:Genes, rRNA; D006090:Gram-Negative Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology; D006094:Gram-Positive Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017213:Root Caries / Q000382:microbiology*; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S