AIST played a central role in obtaining pharmaceutical regulatory approval

AIST functioned as the secretariat to create and publish "Guidelines for Development of Dental Prosthetic Devices Using 3D Additive Manufacturing Technology" with the aim of promoting the development of dental prostheses. Based on the guidelines, IDS Co., Ltd. applied for pharmaceutical regulatory approval for manufacturing and marketing of the cobalt-chromium alloy powder. AIST prepared the conditions for practical application by investigating the microstructure of the additive manufacturing material and clarifying the effects of particle size and layering direction on durability. These reduced the susceptibility to breakage and enabled to manufacture the ideal artificial teeth for the patient in a short time. By automatic additive manufacturing at night and then finishing the artificial teeth the next morning, the manufacturing time can be shortened. This technology realized a tensile strength and elongation at break on the same level as that of forged materials, which could not be achieved by conventional dental casting technology. In addition, the fatigue strength after repeated loading of up to 10 million times was twice that of forged materials. A series of research showed that repeated melting and rapid solidification of the powder result in a metal structure with finely dispersed precipitates, which realizes high strength, high ductility, high durability, and high corrosion resistance.