INTRODUCTION: Current surgical implants utilizing non-resorbable metals (Titanium, Stainless Steel, etc.) often require secondary surgical procedures for removal in the growing skull. Due to the robust growth parameters of the infantile skull, these implants need to exhibit strength on the scale of months but can then serve to alter or impede normal growth if left in situ1. Robust but degradable metallic implants have been used clinically for orthopedic applications and could revolutionize surgical strategies for subsets of these patients2. METHODS: Magnesium alloy was used to mimic key physical properties of FDA approved pediatric stainless steel cranial implants. These were bench tested and assessed on a large animal model for size, shape, fit/adherence, and surgical implant feasibility. Additional bench testing was performed for degradation properties and iterative optimization of implant design3. RESULTS: Multiple implant designs have been achieved that closely match the physical properties of comparative conventional stainless-steel implants. DISCUSSION & CONCLUSIONS: We now have met sufficient criteria for a potentially clinically applicable prototype, have designed a live large animal survival surgery protocol and are awaiting approval to evaluate for safety and degradation.

Birth defects and injuries are frequently treated by surgical procedures, which in some cases require the use of medical implants. Employing biodegradable materials for making surgical implants offers the opportunity to avoid secondary surgery when their explanation is necessary. Our research explores different fabrication techniques for making a medical implant out of biodegradable magnesium alloy. Further, the development and testing of an apparatus capable of quantifying corrosion degradation under stress of a bioresorbable medical implants will be presented. A variety of precision manufacturing methods have been employed to fabricate the medical implant using a magnesium alloy pre-processed in different forms. Finite element analysis (FEA), enabled by Siemens NX and Simcenter 3D software, was used to simulate the mechanical properties and optimize the implant design. Testing of this device required creating an apparatus for performing corrosion under stress and measuring metal degradation based on established procedures. Implants of different shapes and sizes have been manufactured from a magnesium alloy. Some of them have been coated with protective coatings to control their corrosion. Based on the created CAD models, zones of mechanical changes have been located that align with the identified regions of heightened corrosion during the degradation tests under stress. Further, testbeds for corrosion under stress were designed and tested. Optimized design of a magnesium-based biodegradable implant has been achieved, and multiple devices have been fabricated in preparation of the coming in vivo tests. In addition, corrosion-testing apparatuses were developed to evaluate the metal alloy degradation under stress.