MSC - Page 34

PERIODONTICS Scaffolds of silk fibroin were used for ligament tissue engineering applications (31), (32). Mesenchymal stem cells were seeded on a hybrid scaffold, comprised of knitted silk fibroin and aligned silk fibroin electrospun fibers, and led to the expression and production of ligament-related proteins (32). 2.2 Silk fibroin in bone regeneration Silk fibroin scaffold may be a good substitute for bone regeneration with better results than a commercially available polylactic acid scaffold (33). In vitro study showed that silk fibroin led to increase activity of the obsteoblasts than polylactic acid, while the in vivo tests revealed that the silk fibroin scaffold regenerated 78.30% of the original bone volume, while the polylactic acid implantation led to only 49.31% bone formation in rats (33). Also silk fibroin hydrogels injected in critical-sized defects in rabbits resulted in greater trabecular bone volume and thickness,significantly higher mineral and rate of bone formation when compared to PLGA copolymer of polylactic-polyglycolid acid (34). Not only scaffolds, but also silk fibroin membranes proved bone regeneration abilities in animal studies (35). Silk fibroin nanofiber membranes were implanted in calvarial defects of rabbits for guided bone r