POWRE: Bone Cell Ingrowth and Strength Characteristics of Microporous Titanium for Skeletal Repair

Northwestern University, Evanston IL

Investigators

Abstract

0074921 Brinson An award under the POWRE program will enable the PI to gain expertise in bioengineering, biomaterials and implant mechanics to add to her experience in mechanics and materials in general. This research will begin an investigation of microporous titanium (Ti foam) for use as a bone implant material. There are several motivations for this work: First, the stiffness mismatch between current metallic implant materials and the surrounding bone can cause stress-shielding, leading to bone resorption and eventual implant failure. The development of completely porous metallic implants where the material is designed to more closely mimic natural bone properties will help reduce stress shielding problems experienced in current implants. Second, bone cement failure and cement debris also have a detrimental impact on implants, which is avoidable by use of a porous/cementless implant material. Third, development of a fully porous material with controllable microstructure will enable design of implants with improved functionality for tissue attachment as well as unique incorporation of other synthetic materials (e.g., polymer or ceramic coatings or surfaces). In addition to porosity level, pore shape and orientation will clearly affect the mechanical properties and extent of cell ingrowth. Thus, investigation of porous microstructures to identify those which will accelerate and enhance bone ingrowth, while retaining mechanical strength, would provide critical new information for design of bone implants, both to reduce failure rates and to improve quality of life for patients by rapid implant integration. The proposed work will specifically involve **Mechanical testing and finite element analysis to ascertain stiffness and strength properties of the Ti foam samples; and **Cell growth studies performed on Ti foam samples seeded with bone cells and examined at intervals for ingrowth. ***