Assessment of Bisphenol A Release by Orthodontic Aligners : In Vitro Study

Abstract

Background : In orthodontic practice, for several years we have witnessed the rise of orthodontics for adults who are particularly concerned about their appearance and who most often refuse conventional metal multi-brackets. Technological advances and new materials currently allow patients to receive orthodontic treatments with invisible devices, namely orthodontic aligners. Although the thermoplastic materials that make up these aligners are biocompatible, they are not inert; In order to protect the health of our patients, it has been proposed to demonstrate a possible release of bisphenol A (BPA) by orthodontic aligners and to determine its concentration through an in vitro study. 
Methods : Our sample consisted of 10 new orthodontic aligners "SCHEU Dental Clear Aligner®" and 10 aged orthodontic aligners from the same supplier recovered after an average stay in the mouth of 15 days. Each aligner was immersed in 30 ml of artificial saliva. Samples were taken regularly for 2 weeks to monitor a possible release of bisphenol over time by high performance liquid chromatography (HPLC).
Results : Interpretation of the chromatograms of bisphenol samples in new and aged aligners did not show traces of bisphenol for up to 8 weeks.
Conclusion: Further research with a larger sample and a longer duration will lead to more conclusive results since current scientific data report effects at very low doses.