Comparative Evaluation of Bisphenol-A Released from Five Different Orthodontic Aligners - An In vitro Study Using Gas Chromatography Coupled with Mass Spectrometry.

Abstract

Background: Bisphenol A (BPA) monomer is used during the production of a wide variety of orthodontic materials such as composites, aesthetic brackets, and thermoplastic aligners; its release from incomplete polymerisation and resin degradation poses serious health risks. Hence, this study aims to assess BPA release from different aligners at various time intervals of its usage in an in vitro model.

Aim and objectives: To qualitatively and quantitatively determine BPA released from five different orthodontic aligners, at different time intervals.

Materials and methods: Five different orthodontic aligners, namely Dentcare aligner, Invisalign aligner, SD align, Smile aligner, and TAC aligners, were evaluated for BPA release by subjecting the aligners to surface abrasion, immersing in artificial saliva, and subjecting to thermal shock treatment to simulate oral environment at various time intervals (24 hours, 7 days, and 10 days) using gas-phase chromatography.

Statistical analysis used: Descriptive statistics (frequency and percentages) were employed to describe the study results.

Result: BPA was not detected and thus could not be analysed in the present study at different time points. The other elements were identified, which were totally different from one another at each time points.

Conclusion: It is concluded that BPA was not released from the various aligners at any time intervals. The presence of other components such as diethyl phthalate (DEP), which is more or less similar to BPA in terms of inducing toxicity to the liver and other tissues, is a matter of concern and needs further research.