Metal Additive Manufacturing of Multi-Material Dental Strut Implants

The demand for high flexibility and mass customization within medical implants has resulted in the early adoption of additive manufacturing technologies in the medical sector. Apart from offering unique customization opportunities, metal additive manufacturing of implants also enables the generation of functionally structured surfaces showing increased biocompatibility. The need for improving properties like biocompatibility is essential since many patients suffer from dental implant failures such as screw loosening, integration failure or implant breakage. The high requirements for implant materials depending on the specific implant environment and function complicates the implant design and results in multi-component implants. This could be overcome by the use of multi-material metal additive manufacturing that enables functionally graded part production. However, current commercial laser powder-bed fusion systems are limited to a single material at a time. By utilizing an open-architecture laser powder-bed fusion system by Aurora Labs it was possible in a controlled way to mix AISI 316L Stainless Steel with AISI 440C Stainless Steel during the fabrication of a dental strut-like geometry thereby functionally grading the properties of the material to have a low hardness near the gums and a higher hardness around the crown. The material distribution was evaluated by cutting and etching and the hardness was measured at various locations. The current work demonstrates the technical viability of manufacturing functionally graded dental strut implants by leveraging multi-material metal additive manufacturing.