Additive manufacturing of dental polymers: An overview on processes, materials and applications.

Additive manufacturing (AM) processes are increasingly used in dentistry. The underlying process is the joining of material layer by layer based on 3D data models. Four additive processes (laser stereolithography, polymer jetting, digital light processing, fused deposition modeling) are mainly used for processing dental polymers. The number of polymer materials that can be used for AM in dentistry is small compared to other areas. Applications in dentistry using AM are limited (e.g. study models, maxillo-facial prostheses, orthodontic appliances etc.). New and further developments of materials are currently taking place due to the increasing demand for safer and other applications. Biocompatibility and the possibility of using materials not only as temporarily but as definitive reconstructions under oral conditions, mechanically more stable materials where less or no post-processing is needed are current targets in AM technologies. Printing parameters are also open for further development where optical aspects are also important.