Histological evaluation of osteogenesis of 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds in a rabbit model

Utilizing a suitable combination of lactide and glycolide in a copolymer would optimize the degradation rate of a scaffold upon implantation in situ. Moreover, 3D printing technology enables customizing the shape of the scaffold to biometric data from CT and MRI scans. A previous in vitro study has shown that novel 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds had good biocompatibility and mechanical properties comparable with human cancellous bone, while they could support proliferation and osteogenic differentiation of osteoblasts. Based on the previous study, this study evaluated PLGA scaffolds for bone regeneration within a rabbit model. The scaffolds were implanted at two sites on the same animal, within the periosteum and within bi-cortical bone defects on the iliac crest. Subsequently, the efficacy of bone regeneration within the implanted scaffolds was evaluated at 4, 12 and 24 weeks post-surgery through histological analysis. In both the intra-periosteum and iliac bone defect models, the implanted scaffolds facilitated new bone tissue formation and maturation over the time course of 24 weeks, even though there was initially observed to be little tissue ingrowth within the scaffolds at 4 weeks post-surgery. Hence, the 3D-printed porous PLGA scaffolds investigated in this study displayed good biocompatibility and are osteoconductive in both the intra-periosteum and iliac bone defect models.

[1]  J C Middleton,et al.  Synthetic biodegradable polymers as orthopedic devices. , 2000, Biomaterials.

[2]  Jie Ren,et al.  The bone formation in vitro and mandibular defect repair using PLGA porous scaffolds. , 2005, Journal of biomedical materials research. Part A.

[3]  W C de Bruijn,et al.  In vivo degradation and biocompatibility study of in vitro pre-degraded as-polymerized polyactide particles. , 1995, Biomaterials.

[4]  S. Sen,et al.  Matrix Elasticity Directs Stem Cell Lineage Specification , 2006, Cell.

[5]  Zigang Ge,et al.  Manufacture of degradable polymeric scaffolds for bone regeneration , 2008, Biomedical materials.

[6]  S. Teoh,et al.  Scaffold design and in vitro study of osteochondral coculture in a three-dimensional porous polycaprolactone scaffold fabricated by fused deposition modeling. , 2003, Tissue engineering.

[7]  E. D. Rekow,et al.  Performance of hydroxyapatite bone repair scaffolds created via three-dimensional fabrication techniques. , 2003, Journal of biomedical materials research. Part A.

[8]  Robert Langer,et al.  In vivo engineering of organs: the bone bioreactor. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[9]  H. Seitz,et al.  Three-dimensional printing of porous ceramic scaffolds for bone tissue engineering. , 2005, Journal of biomedical materials research. Part B, Applied biomaterials.

[10]  Anthony Atala,et al.  Methods Of Tissue Engineering , 2006 .

[11]  Frédéric Marin,et al.  A marriage of bone and nacre , 1998, Nature.

[12]  E. Tan,et al.  Proliferation and Differentiation of Human Osteoblasts within 3D printed Poly-Lactic-co-Glycolic Acid Scaffolds , 2009, Journal of biomaterials applications.

[13]  O. Suzuki,et al.  Implanted octacalcium phosphate (OCP) stimulates osteogenesis by osteoblastic cells and/or committed osteoprogenitors in rat calvarial periosteum , 1999, The Anatomical record.

[14]  E H Burger,et al.  Mineralization processes in demineralized bone matrix grafts in human maxillary sinus floor elevations. , 1999, Journal of biomedical materials research.

[15]  Katsutoshi Motegi,et al.  Implantation of Octacalcium Phosphate (OCP) in Rat Skull Defects Enhances Bone Repair , 1999 .