Multiscale Porosity Directs Bone Regeneration in Biphasic Calcium Phosphate Scaffolds

作者：Laurence E. Rustom, Thomas Boudou, Brett Nemke, Yan Lu, David J. Hoelzle, Mark D. Markel, Catherine Picart, Amy J. Wagoner Johnson · 发表于：ACS Biomaterials Science & Engineering · 年份：2016 · DOI：10.1021/acsbiomaterials.6b00632 · 被引用次数：46 · 研究领域：Bone Tissue Engineering Materials、Dental Implant Techniques and Outcomes、Orthopaedic implants and arthroplasty

Large and load-bearing bone defects are challenging to treat and cause pain and disfigurement. The design of efficacious bone scaffolds for the repair of such defects involves a range of length scales from the centimeter down to the micrometer-scale. Here, we assess the influence on bone regeneration of scaffold rod spacing (>300 μm) and microporosity (<50 μm), as well as the combination of different structures and materials in the same scaffold, i.e., at the millimeter scale. We use four single-domain scaffolds, microporous (MP) or nonmicroporous (NMP) and with either a “small” or “large” rod spacing. Multidomain scaffolds combine four regions corresponding to the macro- and microarchitectures of the single-domain scaffolds. The scaffolds are implanted in pig mandibles for 3 weeks and bone regeneration is assessed by measuring the average bone volume fraction,, the bone distribution and the trabecular thickness from micro-CT data. For the single-domain scaffolds, was 45 ± 3% for MP-small, 39 ± 2% for MP-large, 25 ± 2% for NMP-small, and 25 ± 2% for NMP-large. MP scaffolds have significantly higher and a more uniform bone distribution compared to NMP, regardless of rod spacing. The average trabecular thickness is significantly larger in MP compared to NMP, and in “large” compared to “small” scaffolds. Microporosity affects trabecular thickness throughout the scaffold, while rod spacing affects it only at the scaffold periphery. In multidomain scaffolds, MP-large and NMP-large...