title: Molecular detection of bacteria associated to caries activity in dentinal lesions.
abstract: OBJECTIVE
  This study aimed at identifying and quantifying Actinomyces naeslundii, Bifidobacterium spp., Streptococcus mitis group, Lactobacillus acidophilus, Lactobacillus casei group, Streptococcus gordonii, and Streptococcus mutans in active and inactive carious dentine lesions of children with early childhood caries by using quantitative polymerase chain reaction.
  
  
  METHODS
  Fifty-six dentin lesion samples, classified as active (n = 39) or inactive (n = 17), were collected from children aged from 2 to 5 years old. Dentinal-cavitated lesions were evaluated by Nyvad criteria for the assessment of caries lesion activity.
  
  
  RESULTS
  Relative quantification revealed that Bifidobacterium spp. and the L. casei group were significantly more abundant in active dentin lesions (p < 0.05). Concentrations of A. naeslundii, S. mitis group, and S. gordonii were not significantly different when comparing dentin lesion activity. The relative proportion of S. mutans was significantly greater in inactive than in active lesions (p < 0.05). Bifidobacterium spp. and L. casei group demonstrated a positive correlation (p = 0.001) in active lesions. The positive detection of L. acidophilus (odds ratio = 15.1) and S. gordonii (odds ratio = 7.7) was significantly associated to the active lesions.
  
  
  CONCLUSIONS
  The data indicate that higher detection levels of Bifidobacterium spp. and the L. casei group may be linked to dentin lesion activity. Additionally, the presence of L. acidophilus and S. gordonii was associated with lesion activity.
  
  
  CONCLUSIONS
  Considering that information about the oral microbiota related to dentin caries activity status is relevant, this study provides insights to better understand the differences in the microbiotas between active and arrested dentin cavities.
authors.affiliation: School of Dentistry, Federal University of Ceará, Sobral, Ceará, Brazil.
authors.forename: Beatriz Gonçalves
authors.initials: BG
authors.lastname: Neves
authors.affiliation: Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Rafael Nóbrega
authors.initials: RN
authors.lastname: Stipp
authors.affiliation: Postgraduate Program in Dentistry; Faculty of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Rua Monsenhor Furtado, s/n, Fortaleza, Ceará, 60430-355, Brazil.
authors.forename: Daniela
authors.initials: D
authors.lastname: da Silva Bezerra
authors.affiliation: Postgraduate Program in Dentistry; Faculty of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Rua Monsenhor Furtado, s/n, Fortaleza, Ceará, 60430-355, Brazil.
authors.forename: Sarah Florindo
authors.initials: SF
authors.lastname: de Figueiredo Guedes
authors.affiliation: Postgraduate Program in Dentistry; Faculty of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Rua Monsenhor Furtado, s/n, Fortaleza, Ceará, 60430-355, Brazil. lidianykarla@yahoo.com.
authors.forename: Lidiany Karla Azevedo
authors.initials: LKA
authors.lastname: Rodrigues
mesh_terms: D001419:Bacteria / Q000302:isolation & purification*; D002675:Child, Preschool; D003731:Dental Caries / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D064307:Microbiota; D016133:Polymerase Chain Reaction
keywords: Bacteria; Child; Dentin caries; Early childhood caries; Quantitative polymerase chain reaction