Bisphenol A Release from Fiber-Reinforced vs. Conventional Stainless-Steel Fixed Retainers: An In Vitro Study

Area of Science:

• Orthodontic Materials Science
• Biomaterials Research
• Analytical Chemistry

Background:

• Bisphenol A (BPA) is a chemical compound used in some dental materials.
• Fiberglass-reinforced composite resins are increasingly used as orthodontic retainers.
• Understanding potential BPA leaching from these materials is crucial for patient safety.

Purpose of the Study:

• To quantify in vitro Bisphenol A (BPA) release from two common fiberglass lingual retainers.
• To compare BPA release from fiberglass retainers with a conventional stainless-steel orthodontic retainer.

Main Methods:

• Three retainer types (Ribbond, EverStick Ortho, Wildcut wire) were tested on extracted teeth.
• BPA release was measured using liquid chromatography-tandem mass spectrometry at multiple time points up to 30 days.
• Statistical analysis involved a two-way mixed, repeated-measures ANOVA.

Main Results:

• Higher BPA levels were detected from polyethylene and glass fiber retainers compared to the stainless-steel control.
• No statistically significant differences in BPA release were found between the retainer systems over the 30-day period.
• The highest BPA concentrations for all groups were observed at the 1-month measurement point.

Conclusions:

• In vitro BPA release during the initial month of use did not significantly vary among the tested fiberglass and stainless-steel orthodontic retainers.
• BPA concentrations peaked at 1 month, suggesting potential accumulation or degradation over time.
• Further research may be warranted to assess long-term BPA release and clinical implications.