title: The influence of orthodontic fixed appliances on the oral microbiota: a systematic review.
abstract: OBJECTIVE
  To investigate whether there is scientific evidence to support the hypothesis that the presence of orthodontic fixed appliances influences the oral microbiota.
  
  
  METHODS
  The search for articles was conducted in PubMed; ISI Web of Knowledge and Ovid databases, including articles published in English until May 17th, 2012. They should report human observational studies presenting the following keywords: "fixed orthodontic appliance" AND "microbiological colonization"; OR "periodontal pathogens"; OR "Streptococcus"; OR "Lactobacillus"; OR "Candida"; OR "Tannerella forsythia"; OR "Treponema denticola"; OR "Fusobacterium nucleatum"; OR "Actimomyces actinomycetemcomitans"; OR "Prevotella intermedia"; OR "Prevotella nigrescens"; OR "Porphyromonas gingivalis". Articles were previously selected by title and abstract. Articles that met the inclusion criteria were analyzed and classified as having low, moderate or high methodology quality. A new detailed checklist for quality assessment was developed based on the information required for applicable data extraction for reviews. The study design, sample, follow-up period, collection and microbial analysis methods, statistical treatment, results and discussion were assessed.
  
  
  RESULTS
  The initial search retrieved 305 articles of which 33 articles were selected by title and abstract. After full-text reading, 8 articles met the inclusion criteria, out of which 4 articles were classified as having low and 4 as moderate methodological quality. The moderate methodological quality studies were included in the systematic review.
  
  
  CONCLUSIONS
  The literature revealed moderate evidence that the presence of fixed appliances influences the quantity and quality of oral microbiota.
authors.forename: Amanda Osório Ayres
authors.initials: AO
authors.lastname: Freitas
authors.forename: Mariana
authors.initials: M
authors.lastname: Marquezan
authors.forename: Matilde da Cunha Gonçalves
authors.initials: Mda C
authors.lastname: Nojima
authors.forename: Daniela Sales
authors.initials: DS
authors.lastname: Alviano
authors.forename: Lucianne Cople
authors.initials: LC
authors.lastname: Maia
mesh_terms: D001419:Bacteria / Q000145:classification*; D003773:Dental Plaque / Q000382:microbiology; D006801:Humans; D009055:Mouth / Q000382:microbiology*; D009967:Orthodontic Appliances / Q000382:microbiology*
keywords: Attachment sites; Microbiological analysis; Microbiology; Orthodontic appliances; Periodontics