Bone Healing

We design and fabricate customized, load-bearing polymer and metal scaffolds for improved bone healing. We evaluate biomaterial efficacy using both in vitro models and in vivo models of bone injury and disease.

Why bone healing?

Treatment of large bone defects resulting from traumatic injury or tumor resection represents a significant challenge for orthopedic surgeons. Despite advances in therapeutics (e.g., recombinant protein technologies), the materials used for fixation of bone (to stabilize it and promote healing) are often much stronger than bone, which can lead to stress shielding, poor osseointegration, implant loosening/failure, pain, and revision surgeries for removal of the implant.

We design and fabricate customized, load-bearing polymer and metal scaffolds for improved bone healing.

Surface Modifications



3D Printed Polymers

We are using 3D printing to create customized, load-bearing thermoplastic polymer scaffolds, and surface functionalization techniques to enhance bioceramic coatings of the polymers (e.g., polylactic acid, poly(lactic-co-glycolic acid), and poly(B-caprolactone)). Utilizing these technologies, our goal is to engineer patient-specific biomaterials that mimic both the mechanical and biological properties of native bone tissue.



Magnesium

We are also exploring biodegradable magnesium and its alloys for use in temporary implants. Material characterization techniques such as surface profilometry and surface chemistry analysis are used to assess the ability of surface coatings and alloying to modulate the degradation of the alloys, to enhance material performance in the physiological environment. Future work will include cytotoxicity, biocompatibility, and novel alloy development of magnesium-based materials.


Dental Implants- BioHorizons

We are evaluating cell function on Ti64 disks with varying surface topographies, which can be beneficial for fixation and osseointegration of dental implants.


Composite Materials



Polymer-Based Composite Printing

The development of 3D printed polymer-based composites (blended with bioceramics or metals) for bone tissue engineering and fracture fixation will enable customized scaffold structures (e.g., controllable porosity, pore shape and size) with enhanced mechanical and biological properties (e.g., osteoconductivity/inductivity). The pneumatic, syringe-based, and thermoplastic printing approaches allow flexibility in material selections and combinations, and the capability of incorporating bioactive materials (e.g., growth factors and living cells) into the polymer substrate for tissue regenerative applications. We have established a systematic concept-verification system from material preparation, fabrication, post-printing modifications, to structural/surface characterizations and mechanical and in vitro testing. Our goal is to provide personalized (made to order) implants, avoid revision surgeries, minimize pain, and maximize the improvement of quality of life.


Biomechanical Characterization of Orthopedic Implants



Simulating TLIF human spine procedure- Medtronic

We are developing a drop-weight insertion tool testing setup for repeatable measurements of force and displacement which simulate those of the human spine during the TLIF procedure. This work will allow for determining impact forces that could ultimately lead to implant failure or deformation, which will help refine implant design and surgical techniques to avoid such risks.


Perfusion and Compression Bioreactor

Our objective is to develop a perfusion-compression bioreactor system that will apply physiological mechanical loading and perfusion flow regimes to a bone explant integrated with an orthopedic implant to study osseointegration. By replicating in vivo forces known to promote bone healing in animal models, osseointegration can be studied in vitro over a longer period of time and with greater physiological relevance than in static culture alone. Long term, we expect the bioreactor to aid with preliminary osseointegration studies before an implant is tested in an animal model.


Biomechanical Characterization of Fracture Fixation and Healing

Fractures, notably those resulting from high-energy traumas such as vehicular impacts or falls, are often complex/oblique in nature, are challenging to treat, and can result in implant loosening or failure, especially in non-compliant veterinary patients. With collaborators at MSU’s College of Veterinary Medicine, we design and construct customized mechanical testing devices to simulate anatomical loading geometries and evaluate the efficacy of: (i) novel fixation devices for stabilizing bone fractures, and (ii) therapeutics for bone healing in large animal models.