Study of the Electrochemical Corrosion Rate of Medical Implants of Titanium and Stainless Steel Made by Machining and selective laser melting under Different Surface Conditions

Replacing missed teeth with artificial metallic implants is a pervasive treatment nowadays. With the advent of research on biomedical and mechanical properties of oral and dental issues, implants have seen a great deal of improvement in terms of dimensions, design of body and materials, methods of production and surface type. Performance of implants in the teeth is affected by oral conditions and phenomena such as corrosion and fatigue along the life time. In this study, the corrosion phenomenon has been experimentally studied with similar oral conditions in a variety of dental implants, focusing on construction methods, materials, and surface conditions. The combination of various fabrication methods, such as machining and 3D printing (selective laser melting) for steel and titanium specimens with a variety of surface conditions, including samples with different threads and samples with biocompatible coatings is applied in the survey. Results show that in general, by increasing the complexity of the implant surface, which includes the method of selective laser melting or creating higher ripeness at the surface by adding a second thread, machining variant depth thread or applying appropriate coating on the surface, hydroxyapatite coating, the resistance to corrosion of the implants will be improved. Also the results show that titanium alloys have a higher corrosion resistance than stainless steels. In addition, applying modern manufacturing methods in the production of implants, particularly three-dimensional printing techniques such as selective laser melting, used in this survey, improves the implant's mechanically performance specially Corrosion resistance rather than the conventional machining method.