title: In-vivo evaluation of the bacterial contamination and disinfection of acrylic baseplates of removable orthodontic appliances.
abstract: BACKGROUND
  This randomized clinical trial assessed, by using microbial culture and scanning electron microscopy (SEM), the contamination by mutans streptococci (MS) colonies/biofilms on acrylic baseplates of removable orthodontic appliances and evaluated the efficacy of antimicrobial sprays (Periogard [Colgate-Palmolive Ind. Brasileira, Osasco, SP, Brazil], Cepacol [Merrell Lepetit Farmacêutica e Industrial Ltda, Santo Amaro, SP, Brazil], and sterile tap water [control]) on their disinfection.
  
  
  METHODS
  Seventeen children were randomly enrolled in a 3-stage changeover system with a 1-week interval between each stage. All solutions were used in all stages by a different group of children. The acrylic baseplates were worn full time except at meals. At the end of each week of the trial, the baseplates were submitted to a randomized disinfection protocol and were sent for microbiologic analysis. New baseplates were constructed, and the same sequence of procedures was repeated 2 more times. Acrylic baseplates representing each test solution were examined by SEM. The Friedman test assessed differences at the 5% significance level among the solutions for MS biofilm formation on acrylic surface.
  
  
  RESULTS
  Cepacol and Periogard reduced the formation of MS colonies/biofilms, and both solutions differed statistically from sterile tap water (P <.001). However, Periogard was significantly more effective against MS than Cepacol (P <.001). When MS colonies/biofilms were detected on acrylic surfaces under stereomicroscopy, this was confirmed with SEM.
  
  
  CONCLUSIONS
  Acrylic baseplates of removable orthodontic appliances worn by children were contaminated by MS colonies/biofilms in all cases after 1 week. Although Cepacol had better results than sterile tap water, spraying with Periogard showed significantly greater efficacy in reducing MS colonies/biofilms on acrylic surfaces.
authors.affiliation: Department of Pediatric Clinics, Preventive and Social Dentistry, Faculty of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Fernanda Campos Rosetti
authors.initials: FC
authors.lastname: Lessa
authors.forename: Carla
authors.initials: C
authors.lastname: Enoki
authors.forename: Izabel Yoko
authors.initials: IY
authors.lastname: Ito
authors.forename: Gisele
authors.initials: G
authors.lastname: Faria
authors.forename: Mirian Aiko Nakane
authors.initials: MA
authors.lastname: Matsumoto
authors.forename: Paulo
authors.initials: P
authors.lastname: Nelson-Filho
mesh_terms: D000180:Acrylic Resins; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D002594:Cetylpyridinium / Q000494:pharmacology*; D002648:Child; D002710:Chlorhexidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D015169:Colony Count, Microbial; D018592:Cross-Over Studies; D019551:Dental Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D009968:Orthodontic Appliances, Removable / Q000382:microbiology*; D016037:Single-Blind Method; D013295:Streptococcus mutans / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000180:Acrylic Resins; D000891:Anti-Infective Agents, Local; D019551:Dental Disinfectants; D002594:Cetylpyridinium; C010882:chlorhexidine gluconate; D002710:Chlorhexidine