title: Efficacy of three hygienic protocols in reducing biofilm adherence to removable thermoplastic appliance.
abstract: OBJECTIVE
  To examine the ability of a removable thermoplastic appliance (RTA) to adsorb hygienic solutions and inhibit bacterial growth and to examine the efficacy of three hygiene protocols in reducing bacterial biofilm adherence to RTA.
  
  
  METHODS
  Solution adsorption and bacterial growth inhibition were examined in vitro using paper vs RTA discs. Subsequently, 11 patients treated with RTA (mean age, 29.1 ± 4.7 years) were assigned into a sequence of three hygiene protocols: regular RTA brushing (baseline), immersion RTAs in chlorhexidine mouthwash (CHX), and using a vibrating bath with cleaning solution (VBC). For each patient, 12 upper RTAs were examined (2 baseline RTAs, 5 CHX RTAs, and 5 VBC RTAs), for a total of 132 RTAs. All RTAs were stained with gentian violet, and biofilm presence was measured using a photodensitometer.
  
  
  RESULTS
  The RTA discs did not adsorb CHX or cleaning solution. The later agent did not show antibacterial features. Baseline RTAs showed significant biofilm adherence (P < .001) on the posterior palatal side of the aligner and on the anterior incisal edge. CHX and VBC hygienic protocols significantly (P < .001) reduced baseline biofilm adherence by 16% and 50%, respectively. Hygienic improvement was maintained over 140 days when CHX and VBC were used. However, VBC was three times more efficient than CHX.
  
  
  CONCLUSIONS
  This study highly recommends the use of a VBC protocol. Biofilm deposits on the RTA, especially on incisal edges and attachment dimples, could lead to inadequate tooth/RTA and attachment/RTA overlap and consequently impair tooth alignment.
authors.affiliation: a  Lecturer, Department of Orthodontics, The Maurice and Gabriela Goldschleger School of Dental Medicine, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Nir
authors.initials: N
authors.lastname: Shpack
authors.forename: Ronit Bar-Ness
authors.initials: RB
authors.lastname: Greenstein
authors.forename: Dana
authors.initials: D
authors.lastname: Gazit
authors.forename: Rachel
authors.initials: R
authors.lastname: Sarig
authors.forename: Alexander Dan
authors.initials: AD
authors.lastname: Vardimon
mesh_terms: D000327:Adsorption; D000328:Adult; D001422:Bacterial Adhesion / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects; D002710:Chlorhexidine / Q000627:therapeutic use; D002985:Clinical Protocols; D004396:Coloring Agents; D003764:Dental Materials / Q000737:chemistry; D003902:Detergents / Q000627:therapeutic use; D004866:Equipment Contamination / Q000517:prevention & control; D005240:Feasibility Studies; D005260:Female; D005840:Gentian Violet; D006801:Humans; D007101:Immersion; D008297:Male; D008422:Materials Testing; D009067:Mouthwashes / Q000627:therapeutic use; D009910:Oral Hygiene / Q000379:methods*; D009968:Orthodontic Appliances, Removable / Q000382:microbiology*; D010969:Plastics / Q000737:chemistry; D013010:Sonication; D016986:Streptococcus sobrinus / Q000187:drug effects / Q000254:growth & development; D013499:Surface Properties; D014099:Toothbrushing / Q000379:methods
chemical_list: D004396:Coloring Agents; D003764:Dental Materials; D003902:Detergents; D009067:Mouthwashes; D010969:Plastics; D005840:Gentian Violet; D002710:Chlorhexidine