Oriented bone regenerative capacity of octacalcium phosphate/gelatin composites obtained through two-step crystal preparation method

Abstract

The present study was designed to investigate whether composite of coprecipitating octacalcium phosphate and gelatin (C-OCP/Gel) has an effect in repairing critical-sized defect of rat calvaria with oriented regenerative bone if implanted. The materials were prepared through two steps to disperse homogenous and well-elongated OCP toward long axis of the crystals in gelatin (Gel) matrix with the distinct concentration 17-44 wt %: OCP precipitates recovered from the coprecipitated with Gel molecules in aqueous solution (referred to as C-OCP hereafter) were mixed again in fresh aqueous Gel solution with various mixing ratio to form C-OCP/Gel for implantation. C-OCP/Gel disks with 9 mm diameter and 1 mm thickness after the dehydrothermal treatment was implanted in 9 mm diameter rat calvaria critical-sized defect. The histology, the histomorphometry in the regenerated bone and the quantitative analysis of the orientation of collagen with picrosirius red staining were carried out. It was found that C-OCP/Gel is capable of not only inducing sufficiently regenerative bone over 80% of the defect coupled with practically complete material biodegradation but also forming oriented bone significantly in relation to the amount of C-OCP in Gel matrix until 12 weeks after the implantation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1029-1039, 2017.

Osteogenic cellular activity around onlaid octacalcium phosphate‐gelatin composite onto rat calvaria

“…These results strongly suggest that bone augmentation by OCP/Gel with PTFE advances under the inhibition of osteoclastogenesis. 54 The Gel matrix may support the OCP efficacy to induce new bone formation with a better quality. All onlaid materials without PTFE enhanced RANKL expression but also inhibited OPG expression in comparison with OCP/Gel with PTFE, resulting in the enhancement of TRAP-positive osteoclast-like cells (Fig.…”

“…Although OCP with PTFE enhanced RANKL expression but osteoclast genesis could be inhibited by the OPG expression. 54 As a result, OCP may increase the number of oriented collagen fibers and bone quality in the new bone. 5).…”

Octacalcium phosphate/gelatin composite facilitates bone regeneration of critical-sized mandibular defects in rats: A quantitative study

“…The capability of OCP to stimulate the osteoclastic formation and the differentiation of the osteoblasts might be involved in activating bone metabolism around the implanted site. 37 Thus, it is possible that gelatin molecules present in the compound used in the present study influenced these bone-related cells.…”

“…In the present study, 64% of octacalcium phosphate and in the study of Handa et al, 40% of it was used, leading to the slow release of octacalcium phosphate particles in the composite and maintaining up to sixteen weeks after implanting the materials. On the other hand, according to Ishiko-Uzuka's study, 37 the gelatin matrix might support the OCP efficacy to induce new bone formation with better quality. The capability of OCP to stimulate the osteoclastic formation and the differentiation of the osteoblasts might be involved in activating bone metabolism around the implanted site.…”

In vitro and in vivo assessment of glucose cross‐linked gelatin/zein nanofibrous scaffolds for cranial bone defects regeneration

“…Moreover, gelatin nanofibers can be fabricated from environmentally friendly solvents, such as acetic acid. Due to the improved effects of gelatin nanofibers on cell adhesion, proliferation and differentiation, diverse tissue engineering applications for gelatin nanofibers have been reported, such as skin (Dhandayuthapani, Krishnan, & Sethuraman, ), cartilage (Lam et al, ), and bone tissue engineering (Ishiko‐Uzuka et al, ). However, the fast dissolution in body fluid and the weak mechanical properties of gelatin nanofibrous scaffolds have hindered the widespread applications in tissue engineering.…”