A novel biomimetic polymer scaffold design enhances bone ingrowth

Abstract

There has been recent interest in treating large bone defects with polymer scaffolds because current modalities such as autographs and allographs have limitations. Additionally, polymer scaffolds are utilized in tissue engineering applications to implant and anchor tissues in place, promoting integration with surrounding native tissue. In both applications, rapid and increased bone growth is crucial to the success of the implant. Recent studies have shown that mimicking native bone tissue morphology leads to increased osteoblastic phenotype and more rapid mineralization. The purpose of this study was to compare bone ingrowth into polymer scaffolds created with a biomimetic porous architecture to those with a simple porous design. The biomimetic architecture was designed from the inverse structure of native trabecular bone and manufactured using solid free form fabrication. Histology and μCT analysis demonstrated a 500-600% increase in bone growth into and adjacent to the biomimetic scaffold at five months post-op. This is in agreement with previous studies in which biomimetic approaches accelerated bone formation. It also supports the applicability of polymer scaffolds for the treatment of large tissue defects when implanting tissue-engineering constructs.

Biodegradable composite scaffolds incorporating an intramedullary rod and delivering bone morphogenetic protein-2 for stabilization and bone regeneration in segmental long bone defects

“…[56] Another interesting study found that scaffold architectures that mimic the structure of native bone have exhibited up to a 500% increase in bone volume when compared to defined architectures. [57]…”

Stereolithographic Bone Scaffold Design Parameters: Osteogenic Differentiation and Signal Expression

“…Further, one recent study has revealed the critical importance of 3D porous scaffold structural cues to induce in vivo bone regeneration. 110 In addition to the importance of the design and fabrication of accurate morphology of implantable bone substitutes, 111 it is also essential that the internal geometry closely mimics the native bone tissue to induce bone ingrowth. The inverse trabecular inner architecture of SLAfabricated polybutylene terephthalate scaffolds designed from micro-CT scans of a native cadaveric canine femur exhibited up to six times higher bone growth into and adjacent to the scaffolds, compared with simple porous scaffolds.…”

Citrate‐based biphasic scaffolds for the repair of large segmental bone defects

“…To achieve this, many researchers have looked toward nature to provide insights in the development of biologically inspired approaches, which can meet the biomimetic microarchitectural requirements for bone regeneration . By replicating the native tissue architecture at the macroscales, microscales, and nanoscales, researchers are able to facilitate cell and extracellular matrix compartmentalization to engineer more native‐like and functional tissue .…”