title: Release of bisphenol A from resin composite used to bond orthodontic lingual retainers.
abstract: BACKGROUND
  In this study, we assessed the changes in bisphenol A (BPA) levels in saliva and urine after placing lingual bonded retainers.
  
  
  METHODS
  Liquid chromatography/mass spectrometry was used to examine the BPA levels in the saliva and urine samples collected from 22 volunteers who received a lingual bonded retainer on their mandibular dentition. Samples were collected immediately before placement and 30 minutes, 1 day, 1 week, and 1 month after placement. The time elapsed after placement, type of resin composite (nanohybrid filled flowable resin or conventional hybrid resin), surface prophylaxis, age, and sex were evaluated for their effects on the BPA levels.
  
  
  RESULTS
  The only significant high level of BPA was observed in the saliva collected just after placement of the lingual bonded retainer. Age and sex did not affect the BPA levels. Subjects in the flowable resin group had lower BPA levels than those in the conventional hybrid resin group; pumice prophylaxis decreased the level of BPA released from the conventional hybrid resin at the immediate time point. The salivary BPA level (maximum, 20.889 ng/mL) detected in the samples collected just after placement was far lower than the reference daily intake dose.
  
  
  CONCLUSIONS
  Accordingly, the potential toxicity of BPA from placing lingual bonded retainer might be negligible. On the other hand, because the health-effective amount of BPA is controversial, BPA release should be minimized.
authors: Department of Orthodontics, Dental College, Kyung Hee University, Seoul, Korea.
authors: Yoon-Goo
authors: YG
authors: Kang
authors: Ji-Young
authors: JY
authors: Kim
authors: Jaejik
authors: J
authors: Kim
authors: Phil-Jun
authors: PJ
authors: Won
authors: Jong-Hyun
authors: JH
authors: Nam
mesh_terms: D000293:Adolescent; D000328:Adult; D001559:Benzhydryl Compounds; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D016000:Cluster Analysis; D003188:Composite Resins / Q000737:chemistry; D003777:Dental Prophylaxis; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D018704:Orthodontic Retainers; D010636:Phenols / Q000032:analysis* / Q000652:urine; D012044:Regression Analysis; D019279:Resin Cements / Q000737:chemistry*; D012463:Saliva / Q000737:chemistry; D055815:Young Adult; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins; D010636:Phenols; D019279:Resin Cements; C467913:Filtek Flow; C444701:Filtek Z250; C006780:bisphenol A; D000098826:Bisphenol A Compounds