Structural behaviour of CoCrMoTi(Zr) alloys for dental applications

Currently, the prosthesis, both removable and fixed, are usually realized in Co-Cr-Mo alloys, which possess good corrosion resistance owing to the appropriate microstructure, but presents low machinability. Occasionally also allergic responses to the constituents of base metal alloys are observed. Most adverse tissue reactions attributed to the wearing of a base metal removable prosthesis, however, are manifestations of improper design or poor fit. Being the major component, cobalt imparts to the alloy its intrinsic corrosion resistance. Ti is one of the best biocompatible metals and is widely used as implant. In addition, the total weight of the prosthesis can be modified. The purpose of this paper is to develop new dental materials with superior mechanical performance and corrosion resistance as well as higher biocompatibility. The attention was focused on the possibility to obtain a new class of cobalt based alloy by Ti addition. Different composition of CoCrMo base system were obtained by RAV technology, alloying with 2-5%wt. Ti. Different investigations were carried out for the microstructural identification of the constituents either by energy-dispersive X-ray spectroscopy, hardness values determination and mechanical characteristic behaviour. Finally a correlation between structure-mechanical properties due to scanning electronic microscopy was made.