3D Printing of Ceramics for Modern Medical Engineering

Additive manufacturing has become an integral part of modern medical engineering. New approaches in 3D printing of ceramics offer the possibilities to create patient specific medical implants. This work focuses on three promising materials for lithography-based ceramic manufacturing (LCM) in the field of medical applications, based on alumina-toughened zirconia (ATZ), hydroxyapatite (HA) and tricalcium phosphate (TCP). The advantages of ATZ, a composite ceramic material, are good biocompatibility, chemical inertness, high strength, fracture toughness, hardness as well as good abrasion resistance, making this material a very promising candidate for 3D printed permanent implants. Limitations in thin walls usually confine the application fields of ceramics. The feasibility of thick-walled and massive components from ATZ by LCM technology was demonstrated, paving the way to manufacture dental implants and permanent medical inserts like femoral head implants in an industrial scale. Besides, new approaches with HA and TCP have been explored. As these ceramics resemble the chemical composition of the inorganic portion of native bone they are excellent candidates for alloplastic bone substitute materials. They exhibit very good biocompatibility and can even be resorbed and remodeled into bone tissue upon implantation. The production of ceramic implants with defined porosity and freeform shape to imitate natural bone was demonstrated using LCM. Very complex ceramic bone substitute and dental implants in highly reproducible manner were produced successfully.