<i>Actinomyces</i> spp. in Supragingival Plaque of Ethnic Chinese Preschool Children with and without Active Dental Caries

Abstract

Very limited molecular epidemiological data are available on the role of Actinomyces spp. in the pathogenesis of caries in the primary dentition. Therefore, we investigated their distribution in supragingival plaque of ethnic Chinese preschool children from Singapore and Hong Kong, either with or without active caries. Plaque samples were taken from intact interproximal enamel areas using dental floss. Bacterial genomic DNA of each sample was extracted and variable regions of 16S ribosomal DNA amplified and labelled with digoxigenin. Oligonucleotide probes specific for Actinomyces bovis, Actinomyces gerencseriae, Actinomyces israelii, Actinomyces meyeri, Actinomyces odontolyticus, catalase-negative Actinomyces naeslundii (genospecies 1 and 2) and catalase-positive Actinomyces naeslundii genospecies 2 (previously Actinomyces viscosus serotype II) were used to detect these species using Southern hybridization with a Minislot and Miniblotter system. A. odontolyticus, A. gerencseriae and A. meyeri were detected with similar frequency in both Singapore and Hong Kong samples or in those with and without active caries. However, the prevalence of A. naeslundii was significantly different in the two locales (p < 0.05). A. odontolyticus (88.7%), A. gerencseriae (56.6%) and A. naeslundii (50.9%) were detected in a majority of the samples and the positive hybridization signals of A. gerencseriae in the caries-active group were stronger than from the caries-free group. A. bovis and A. israelii were undetectable in any of the samples. These data imply that A. odontolyticus, A. naeslundii and A. gerencseriae may play an important role in supragingival plaque formation on primary teeth in ethnic Chinese, with others such as A. meyeri contributing.

Actinomyces and Related Organisms in Human Infections

“…Actinomyces species play a central role in the initial stages of biofilm formation on teeth (i.e., dental plaque) both above (supragingival) and below (subgingival) the gumline (29). Indeed, A. odontolyticus, A. naeslundii, A. oris, and A. gerencseriae have been shown to participate in the formation of supragingival plaque on primary teeth of children aged 3 to 4 years (30). An interesting observation was that A. israelii, which is considered the major causative agent of human actinomycosis, is uncommon in the oral cavity of young children (28,30).…”

“…Indeed, A. odontolyticus, A. naeslundii, A. oris, and A. gerencseriae have been shown to participate in the formation of supragingival plaque on primary teeth of children aged 3 to 4 years (30). An interesting observation was that A. israelii, which is considered the major causative agent of human actinomycosis, is uncommon in the oral cavity of young children (28,30). In the original description of A. georgiae (17), most characterized isolates came from gingival crevice samples from periodontally healthy children.…”

“…The role of Actinomyces in dental caries is well known; in this context, the most important species are A. gerencseriae and A. israelii (30,180,181). A. gerencseriae in particular is among the most active species in dental plaque of children suffering from severe early childhood caries, which is a chronic disease causing extensive destruction of the primary dentition (181).…”

Phenalen-1-One-Mediated Antimicrobial Photodynamic Therapy and Chlorhexidine Applied to a Novel Caries Biofilm Model

“…For this purpose, a novel biofilm model for high-throughput screening of antimicrobial approaches was established comprising A. naeslundii, A. odontolyticus, and S. mutans. A. naeslundii is considered to be an essential early colonizer in dental plaque [Dige et al, 2009], while A. odontolyticus is suggested to be a key organism mediating adhesion and co-aggregation in supragingival plaque [Tang et al, 2003] and is associated with high caries incidence in children [ElSalhy et al, 2016]. S. mutans is well known to play a major role in the pathogenesis of dental caries, mostly due to its ability to produce an insoluble polymeric matrix and due to its acidogenic and aciduric properties [Klein et al, 2015].…”

SeNPs/PLGA Inhibits Biofilm Formation by Cultivable Oral Bacteria Isolated from Caries-Active Children

“…viscosus, A. gerencseriae, A. odontolyticus, Rothia dentocariosa, Propionibacterium, Prevotella , Veillonella, Bifidobacterium and Scardovia (Karpiński et al, 2009;Liljemark et al, 1993;Tahmourespour et al, 2013;Tang et al, 2003). In preschool children, A. odontolyticus, A. naeslundii and A. gerencseriae have been reported to play an important role in supragingival plaque formation with other bacteria (Tang et al, 2003). Examine bacterial diversity of oral microbiota in saliva and supragingival plaques from 60 children aged 3 to 6 years old with and without dental caries from China (Ling et al, 2010).…”