Aim of the project is the evaluation of the elution of substances from 3D printed aligners immersed in water for 1 week-which corresponds to the time frame of their use. Due to the systematic detection of Bisphenol (BPA) and urethane dimethacrylate (UDMA) in saliva of treated patients with some orthodontic adhesives, targeted analysis will be carried out for the identification of  BPA and UDMA by ESI-LC-MS/MS analysis. Group budget 8.000 SF. Coordinator: A. Hiskia.