title: Release of bisphenol-A from a light-cured adhesive bonded to lingual fixed retainers.
abstract: BACKGROUND
  Our aim was to quantitatively determine the bisphenol-A (BPA) released from a light-cured orthodontic adhesive used to bond lingual fixed retainers.
  
  
  METHODS
  Eighteen recently extracted premolars, divided into 3 groups of 6 teeth each, were embedded in plaster in an arch shape. A light-cured adhesive (Transbond XT, 3M Unitek, Monrovia, Calif) was bonded to a .0195-in, 3-strand heat-treated twist flex wire (Wildcat, GAC International, Bohemia, NY) adjusted to the lingual surface of the teeth, and the arches were immersed in doubled-distilled water for 10, 20, and 30 days. The concentration of BPA in the 3 eluents was investigated with gas chromatography-mass spectroscopy; all assays were performed in triplicate, and the results were averaged.
  
  
  RESULTS
  Measurable amounts of BPA were identified for all groups, with the highest found in the immersion media of the 1-month groups (2.9 μg/L), whereas the control (tooth storage solution) had 0.16 μg/L.
  
  
  CONCLUSIONS
  The BPA released from a light-cured adhesive used to bond lingual fixed retainers might be assigned to the application mode of the material that differs from conventional use. Further testing including estrogenicity assays will assess the potential estrogenic action of this application. Composite restorative resins should replace orthodontic adhesives that were not intended to function with their surfaces in the oral cavity; alternatively, canine-bonded fixed retainers might reduce the amount of adhesive used.
authors.affiliation: Department of Orthodontics, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki, Greece. teliades@ath.forthnet.gr
authors.forename: Theodore
authors.initials: T
authors.lastname: Eliades
authors.forename: Dimitra
authors.initials: D
authors.lastname: Voutsa
authors.forename: Iosif
authors.initials: I
authors.lastname: Sifakakis
authors.forename: Margarita
authors.initials: M
authors.lastname: Makou
authors.forename: Christos
authors.initials: C
authors.lastname: Katsaros
mesh_terms: D000704:Analysis of Variance; D001559:Benzhydryl Compounds; D001641:Bicuspid; D004968:Estrogens, Non-Steroidal / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D018704:Orthodontic Retainers; D010636:Phenols / Q000032:analysis*; D019279:Resin Cements / Q000737:chemistry*; D018709:Statistics, Nonparametric; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004968:Estrogens, Non-Steroidal; D010636:Phenols; D019279:Resin Cements; C477790:Transbond XT; C006780:bisphenol A; D000098826:Bisphenol A Compounds