Defatted Bone Polyurethane Composites for Orthopedic Repair
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current synthetic bone grafts face challenges such as brittle mechanical properties, slow resorption rates, and tissue necrosis due to high temperatures, while autologous bone harvesting is invasive, necessitating the development of improved composite materials for orthopedic applications.
Innovation Solution
The use of injectable and/or moldable composites comprising defatted bone particulates and polyurethane materials with covalent bonding, which enhance mechanical properties and osteoconductive biological properties, facilitating improved interactions and remodeling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ceramic biomaterials such as calcium phosphate cements are used, then biocompatibility and osteoconductivity are improved, but mechanical properties become brittle
Solution Approach 1:
The patent combines ceramic biomaterials (calcium phosphate particles) with polyurethane polymer matrix to create a composite material that exhibits both the biocompatibility/osteoconductivity of ceramics and the mechanical flexibility/toughness of polymers. The composite structure allows each material to contribute its advantageous properties while compensating for the weaknesses of the other.
2Reliability
If ceramic biomaterials such as calcium phosphate cements are used, then biocompatibility is improved, but resorption rate becomes slow
Solution Approach 1:
The patent modifies the resorption characteristics by changing the chemical composition parameters of the composite, specifically incorporating calcium phosphate particles with controlled size distributions and ratios (e.g., 45-55 wt% calcium phosphate, 30-40 wt% polyurethane) to optimize both biocompatibility and resorption rate.
3Ease of operation
If poly(methyl methacrylate) is used, then injectability is improved, but tissue necrosis occurs due to high temperature polymerization
Solution Approach 1:
The patent changes the polymerization temperature parameter by using polyurethane materials that can be injected and set at lower temperatures, avoiding the high-temperature polymerization of PMMA that causes tissue necrosis. The polyurethane system allows for controlled setting at physiological temperatures.
4Ease of operation
If poly(methyl methacrylate) is used, then injectability is improved, but stress-shielding occurs which accelerates resorption of neighboring bone
Solution Approach 1:
The patent modifies the mechanical property parameters by using polyurethane materials with lower modulus of elasticity compared to PMMA, reducing the stiffness mismatch between implant and bone. This decreases stress-shielding effects and prevents accelerated bone resorption while maintaining injectability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
These composites demonstrate increased mechanical strength, faster remodeling, and balanced mechanical and biological properties, making them suitable for various orthopedic applications, including bone defect repair.
Implementation Method 1
composite materials with covalent bonding between particulates (e.g., bone particles and ceramic biomaterials such as calcium phosphate) and polyurethane materials
Data Source
AI summary
The present invention encompasses the finding that certain treatments (e.g., surface modifications) to particulate materials can provide surprising and unexpected benefits and/or features to composites and/or compositions as described herein. In some embodiments, such benefits and/or features may render particular composites and/or compositions particularly useful in a certain therapeutic context (e.g, for repair of tibial plateau, femoral head, craniofacial, or lateral mandibular body defects). The present invention demonstrates that certain composites and/or compositions wherein the particular material is or comprises defatted bone have surprising and beneficial attributes.