Aligned Ice Templated Biomaterial Strategies for the Musculoskeletal System

Abstract

Aligned pore structures present many advantages when conceiving biomaterial strategies for treatment of musculoskeletal disorders. Aligned ice templating (AIT) is one of the many different techniques capable of producing anisotropic porous scaffolds; its high versatility allows for the formation of structures with tunable pore sizes, as well as the use of many different materials. AIT has been found to yield improved compressive properties for bone tissue engineering (BTE), as well as higher tensile strength and optimized cellular alignment and proliferation in tendon and muscle repair applications. This review evaluates the work that has been done in the last decade toward the production of aligned pore structures by AIT with an outlook on the musculoskeletal system. This work describes the fundamentals of the AIT technique and focuses on the research carried out to optimize the biomechanical properties of scaffolds by modifying the pore structure, categorizing by material type and application. Related topics including growth factor incorporation into AIT scaffolds, drug delivery applications, and studies about immune system response will be discussed.

Impact of crystalline domains on long‐term stability and mechanical performance of anisotropic silk fibroin sponges

“…1,15 Ice templating, or freeze-casting, is a technique where ice crystals guide the generation of porosity within a material, as water phase separates from the polymer during the freezing process. [16][17][18] This technique can be useful in materials fabrication where porosity is an important fabrication parameter for mass transfer and cellular organization within a material. Tunable parameters such as freezing time, freezing temperature, and solution composition are among many factors that control porosity and internal structure.…”

“…Tunable parameters such as freezing time, freezing temperature, and solution composition are among many factors that control porosity and internal structure. [16][17][18] Unidirectional ice templating enables fabrication of highly aligned materials through driving a freezing front in one direction across the polymer solution. This is commonly used for skeletal muscle applications, 17 and has been successful in generating aligned silk fibroin scaffolds for muscle applications.…”

“…[16][17][18] Unidirectional ice templating enables fabrication of highly aligned materials through driving a freezing front in one direction across the polymer solution. This is commonly used for skeletal muscle applications, 17 and has been successful in generating aligned silk fibroin scaffolds for muscle applications. 1,3 In this work we utilize sponge-like biomaterial structures by unidirectionally freezing silk fibroin solution, freeze drying the structure, and then inducing crystallinity to produce a water insoluble scaffold, hereinafter referred to as sponges.…”