Comparing the regeneration potential between PLLA/Aragonite and PLLA/Vaterite pearl composite scaffolds in rabbit radius segmental bone defects

Abstract

Mussel-derived nacre and pearl, which are natural composites composed CaCO 3 platelets and interplatelet organic matrix, have recently gained interest due to their osteogenic potential. The crystal form of CaCO 3 could be either aragonite or vaterite depending on the characteristics of mineralization template within pearls. So far, little attention has been paid on the different osteogenic capacities between aragonite and vaterite pearl. In the current work, aragonite or vaterite pearl powders were incorporated into poly- l -lactic acid (PLLA) scaffold as bio-functional fillers for enhanced osteogenesis. In intro results revealed that PLLA/aragonite scaffold possessed stronger stimulatory effect on SaOS-2 cell proliferation and differentiation, evidenced by the enhanced cell viability, alkaline phosphatase activity, collagen synthesis and gene expressions of osteogenic markers including osteocalcin, osteopotin and bone sialoprotein. The bone regeneration potential of various scaffolds was evaluated in vivo employing a rabbit critical-sized radial bone defect model. The X-ray and micro-CT results showed that significant bone regeneration and bridging were achieved in defects implanted with composite scaffolds, while less bone formation and non-bridging were found for pure PLLA group. Histological evaluation using Masson's trichrome and hematoxylin/eosin (H&E) staining indicated a typical endochondral bone formation process conducted at defect sites treated with composite scaffolds. Through three-point bending test, the limbs implanted with PLLA/aragonite scaffold were found to bear significantly higher bending load compared to other two groups. Together, it is suggested that aragonite pearl has superior osteogenic capacity over vaterite pearl and PLLA/aragonite scaffold can be employed as a potential bone graft for bone regeneration.

Accelerated degradation of HAP/PLLA bone scaffold by PGA blending facilitates bioactivity and osteoconductivity

“…Biopolymer/bioceramic composites have attracted increasing attention for their use as scaffold materials in bone tissue engineering because they might combine good processability of biopolymer with excellent bioactivity of bioceramic [ [1] , [2] , [3] ]. Among various biopolymer materials, poly- l -lactic acid (PLLA) is one of the promising materials because of its good biocompatibility and biodegradability [ [4] , [5] , [6] ].…”

3D bioactive cell-free-scaffolds for in-vitro/in-vivo capture and directed osteoinduction of stem cells for bone tissue regeneration

“…Mostly based on ordered incorporation of seed-cells, scaffolds made of biomaterials and osteogenic signaling factors, bone tissue engineering is one of the most effective methods for regeneration of various bones, including weight-bearing bones and non-load-bearing bones [ [1] , [2] , [3] ]. The use of natural or synthetic scaffolds for bone regeneration has been considered as a promising alternative to natural bone grafts [ [4] , [5] , [6] , [7] , [8] , [9] ].…”

In Vitro and In Vivo Characterization of PLLA-316L Stainless Steel Electromechanical Devices for Bone Tissue Engineering—A Preliminary Study

“…The SS316L potential as a non-permanent device for bone remodeling has been widely accepted, and previous groups have been applying this alloy alone or in combination with other biomaterials, showing positive results [ 45 , 46 ]. Previous groups have reported promising outcomes when applying PLLA polymers in bone scaffolding, showing enhanced osteogenesis and proliferation of cell populations from various sources [ 47 , 48 ], as well as positive in vivo outcomes [ 49 ]. Further studies have reported this biomaterial in combination with metal substrates to enhance bone remodeling [ 49 ].…”

“…Previous groups have reported promising outcomes when applying PLLA polymers in bone scaffolding, showing enhanced osteogenesis and proliferation of cell populations from various sources [ 47 , 48 ], as well as positive in vivo outcomes [ 49 ]. Further studies have reported this biomaterial in combination with metal substrates to enhance bone remodeling [ 49 ]. Osteogenic differentiation extension was assessed by Alizarin Red S, with the SS/SIL/PLLA devices presenting greater mineral deposition, when compared to the SS/SIL group ( Figure 3 , Table 3 and Table 4 ).…”