4CPS-163 Leachable analysis of dental materials

<h3>Background and Importance</h3> Knowledge about Leachables gains importance not only in the industrial drug and hospital pharmacy production, but also in the risk assessment of 3D printed medical devices. In the dental department of our hospital, the question arose, whether new 3D printed prostheses could release harmful monomers or additives, which may have an impact on the oral tissues in patients. The question was of particular interest as a result of the modification to the approval process for these materials, which now requires a more comprehensive understanding of their behaviour for the purposes of future procedures. <h3>Aim and Objectives</h3> We aimed identifying and quantifying possible leachables, such as monomers or additives, released from resin-based 3D printing dental biomaterials. The data should be valid for a cooperation project assessing the risk of patient´s exposure with this leachables. <h3>Material and Methods</h3> Based on defined Extraction methods of the USP665 and our own screening method for characterising extractables in syringes for hospital pharmacy production, we prepared ethanolic and aequaous extracts (neutral, pH9 and pH5) of CAD/CAM material Denture Base LP (Fromlabs Inc., Somerville, USA). UDMA analyses were performed by LC-MS (4000 qTrap, Sciex), <h3>Results</h3> We identified and quantified the monomer UDMA (Urethane dimethacrylate), one major component of the resin used for dentures, in all extracts. After 56 days the highest amount of UDMA was found in the ethanolic extracts up to 57,3µg/mL, whereas in all aequous extracts, independent of the pH, it was 3,4µg/mL. Moreover, further peaks were detected indicating further leachables in our extracts. <h3>Conclusion and Relevance</h3> The results of the extraction study revealed that residual monomer release from resin-based biomaterials intended for 3D printing of dental devices occurs and could be detected by the analytical methodology applied in our pharmacy lab. As our data will be further used in a cooperation project for biological toxicity testing and to estimate patient exposure with monomers and leachables in general, it makes sense to open the analytical methods of the pharmacy for other purposes. At least there are analogies between dental laboratory and hospital pharmacy production concerning the approval process. Cooperation is therefore advantageous for both parties. <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest