title: Dental caries and microbiota in children with black stain and non-discoloured dental plaque.
abstract: OBJECTIVE
  We aimed to assess caries experience and microbiota in systemically healthy children with black stain (BS) and non-discoloured plaque.
  
  
  METHODS
  Forty-six children with BS and 47 counterparts with non-discoloured plaque aged 7.9 ± 1.3 years were clinically examined. Dental caries was scored using WHO criteria. Samples of BS and non-discoloured dental plaque were collected from tooth surfaces. The DNA of the samples was extracted and real-time PCR was performed to determine the total number of bacteria and the species Streptococcus mutans, S. sobrinus, Lactobacillus sp., Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum.
  
  
  RESULTS
  Children with BS had lower DMFT (p = 0.013), lower DT values (p = 0.005) and a tendency to lower caries prevalence (p = 0.061) than children with non-discoloured plaque. Plaque samples of the BS group contained higher numbers of A. naeslundii (p = 0.005) and lower numbers of F. nucleatum (p = 0.001) and Lactobacillus sp. (p = 0.001) compared to the non-discoloured plaque samples of the control group. Comparing the children with BS and non-discoloured plaque, higher counts for A. naeslundii (p = 0.013) were observed in caries-free children with BS while in caries-affected children with BS, lower counts of F. nucleatum (p = 0.007) were found. Counts of Lactobacillus sp. were higher in non-discoloured plaque samples than in BS of caries-free and caries-affected children.
  
  
  CONCLUSIONS
  Results suggest that the different microbial composition of BS might be associated with the lower caries experience in affected subjects. The role of black-pigmented bacteria associated with periodontitis needs further studies.
authors: Department of Preventive Dentistry and Paediatric Dentistry, University Hospital Jena, Germany.
authors: R
authors: R
authors: Heinrich-Weltzien
authors: B
authors: B
authors: Bartsch
authors: S
authors: S
authors: Eick
mesh_terms: D000190:Actinomyces / Q000302:isolation & purification; D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification; D058491:Bacterial Load; D002648:Child; D004245:DMF Index; D003731:Dental Caries / Q000382:microbiology*; D003773:Dental Plaque / Q000382:microbiology*; D016967:Fusobacterium nucleatum / Q000302:isolation & purification; D006801:Humans; D007778:Lactobacillus / Q000302:isolation & purification; D016966:Porphyromonas gingivalis / Q000302:isolation & purification; D018713:Prevotella intermedia / Q000302:isolation & purification; D060888:Real-Time Polymerase Chain Reaction; D013295:Streptococcus mutans / Q000302:isolation & purification; D016986:Streptococcus sobrinus / Q000302:isolation & purification; D014075:Tooth Discoloration / Q000382:microbiology*; D014094:Tooth, Deciduous / Q000382:microbiology