title: Prevalence of Helicobacter pylori in the adolescent oral cavity: dependence on orthodontic therapy, oral flora and hygiene.
abstract: BACKGROUND
  Helicobacter pylori (HP) infection usually occurs in childhood. While there are various studies on the prevalence of HP in dental plaque, ours is the first to analyze its prevalence during orthodontic therapy and its interaction with competitive bacteria in adolescents.
  
  
  METHODS
  The prevalence of HP was examined before and during the first 12 weeks of orthodontic therapy with fixed appliances in 11 patients with a mean age of 12.7 years. A total of 93 plaque samples were analyzed using PCR. The data acquired at every consultation were the following: PCR analysis of dental plaque and (13)C urea breath tests for HP, quantitative analyses of saliva for Lactobacilli and Streptococcus mutans, the interproximal plaque index (API), and sulcus bleeding index (SBI).
  
  
  RESULTS
  The prevalence of HP in plaque was 82% before orthodontic therapy, dropping to 54% during therapy (t test, p≤0.05). In contrast to HP's prevalence, the Lactobacilli count rose (p≤0.05). The number of Streptococcus mutans bacteria in saliva decreased during orthodontic therapy (p≤0.05).
  
  
  CONCLUSIONS
  The prevalence of HP in dental plaque amounted to 82%. Orthodontic treatment did not reduce its prevalence. The prevalence of Lactobacilli was inversely proportional to that of HP.
authors: Department of Orthodontics, Hospital Center Ludwig-Maximilian University, Munich, Germany. Andrea.Wichelhaus@med.uni-muenchen.de
authors: Andrea
authors: A
authors: Wichelhaus
authors: Lorenz
authors: L
authors: Brauchli
authors: Qunsheng
authors: Q
authors: Song
authors: Guido
authors: G
authors: Adler
authors: Günter
authors: G
authors: Bode
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D005858:Germany / Q000453:epidemiology; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D009055:Mouth / Q000382:microbiology*; D009910:Oral Hygiene / Q000706:statistics & numerical data*; D009971:Orthodontics, Corrective / Q000706:statistics & numerical data*; D015995:Prevalence