title: Probiotic effects of orally administered Lactobacillus salivarius WB21-containing tablets on periodontopathic bacteria: a double-blinded, placebo-controlled, randomized clinical trial.
abstract: OBJECTIVE
  This study was designed to evaluate whether the oral administration of lactobacilli could change the bacterial population in supra/subgingival plaque.
  
  
  METHODS
  Sixty-six healthy volunteers without severe periodontitis were randomized into two groups to receive lactobacilli or placebo for 8 weeks (8W): the test group (n=34) received 2.01 x 10(9) CFU/day of Lactobacillus salivarius WB21 and xylitol in tablets; the control group (n=32) received placebo with xylitol. Supra/subgingival plaque samples were collected at the baseline and after 4 weeks (4W) and 8W. The bacterial amounts in plaque samples were analysed by quantitative real-time polymerase chain reaction.
  
  
  RESULTS
  The numerical sum of five selected periodontopathic bacteria in the test group was decreased significantly in subgingival plaque at 4W [odds ratio (OR)=3.13, 95% confidence intervals (CI)=1.28-7.65, p=0.012]. Multivariate analysis showed that significantly higher odds were obtained for the reduction of Tannerella forsythia in subgingival plaque of the test group at both 4W (OR=6.69, 95% CI=2.51-17.9, p<0.001) and 8W (OR=3.67, 95% CI=1.45-9.26, p=0.006).
  
  
  CONCLUSIONS
  Oral administration of probiotic lactobacilli reduced the numerical sum of five selected periodontopathic bacteria and could contribute to the beneficial effects on periodontal conditions.
authors.affiliation: Department of Oral Biology, Division of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry, Sendai 980-8575 Japan.
authors.forename: Gen
authors.initials: G
authors.lastname: Mayanagi
authors.forename: Moto
authors.initials: M
authors.lastname: Kimura
authors.forename: Seigo
authors.initials: S
authors.lastname: Nakaya
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Hirata
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Sakamoto
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Benno
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Shimauchi
mesh_terms: D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification; D001439:Bacteroides / Q000302:isolation & purification; D015169:Colony Count, Microbial; D003773:Dental Plaque / Q000382:microbiology; D003774:Dental Plaque Index; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D005884:Gingival Hemorrhage / Q000382:microbiology; D006801:Humans; D007778:Lactobacillus; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000382:microbiology; D010518:Periodontitis / Q000382:microbiology*; D010919:Placebos; D016966:Porphyromonas gingivalis / Q000302:isolation & purification; D018713:Prevotella intermedia / Q000302:isolation & purification; D019936:Probiotics / Q000008:administration & dosage / Q000627:therapeutic use*; D012907:Smoking; D013607:Tablets; D048373:Treponema denticola / Q000302:isolation & purification; D014993:Xylitol
chemical_list: D010919:Placebos; D013607:Tablets; D014993:Xylitol