Release of monomers from orthodontic adhesives

• Orthodontic adhesives contain fillers and resin matrix (bis-GMA, urethane).
• Fluidifiers such as triethylene glycol and polymers such as HEMA can be added.
• Gas phase chromatography-mass spectrometry measures monomers (types, quantities).
• Significant quantities of TEGDMA and bisphenol A have been detected.
• Manufacturers must declare components with potential undesirable side effects.

IntroductionMost composite resins release both bisphenol A (BPA), which disrupts the endocrine balance, and triethylene glycol dimethacrylate (TEGDMA), which has high risks for human health: eg, allergies and cytotoxicity. The aim of this study was to characterize monomers released from orthodontic adhesives.MethodsWe studied samples of orthodontic adhesives by associating 2 techniques: gas phase chromatography and mass spectrometry.ResultsThe in-vitro analysis detected significant quantities of BPA, TEGDMA, and other monomers in orthodontic adhesives used in daily practice: Transbond XT, Transbond Supreme LV (both, 3M Unitek, Monrovia, Calif), Blugloo (Ormco, Orange, Calif), and MonoLok 2 (Rocky Mountain Orthodontics, Denver, Colo).ConclusionsClinicians should consider that orthodontic adhesives contain BPA, an endocrine disruptor; TEGDMA, an allergic and a cytotoxic compound; and carcinogenic genotoxic compounds. These molecules are not mentioned in the material safety data sheets. Manufacturers should declare all components of dental composites to identify these substances that may result in allergic or undesirable side effects for patients and dental staff.