title: In vitro physicochemical properties, osteogenic activity, and immunocompatibility of calcium silicate-gelatin bone grafts for load-bearing applications.
abstract: The use of a composite made of natural polymer gelatin and bioactive calcium silicate resembling the morphology and properties of natural bone may provide a solution to the problem of ceramic brittleness for load-bearing applications. The in vitro bioactivity, degradability, osteogenic activity, and immunocompatibility of three types of calcium silicate-gelatin composite bone grafts were characterized. The osteogenic activity and immunocompatibility were evaluated by incubating the bone grafts with human dental pulp cells. After soaking in a simulated body fluid (SBF) for 1 day, all materials were covered with clusters of "bone-like" apatite spherulites. The control material without gelatin exhibited an insignificant change in strength, degradability, and porosity and a small weight loss of 6% after 180 days of soaking in the SBF solution. In contrast, the soaking time imposed in this study did have a statistically significant effect on compressive strength, porosity, and weight loss of the gelatin-containing composites. After 180 days of soaking, the composite with 10 wt % gelatin lost 47% and 10% in compressive strength and weight, respectively, with a porosity of 23%. However, the presence of gelatin promoted greater cell attachment and proliferation on the composite bone grafts. Pulp cells on the calcium silicate-gelatin bone grafts expressed higher levels of osteocalcin, osteopontin, and bone sialoprotein. The inhibition of inducible nitric oxide synthase and interleukin-1 expression and the activation of interleukin-10 were increased with increasing gelatin content. Overall, these findings provide evidence that composite bone grafts containing 10 wt % gelatin with a high initial strength were bioactive, nontoxic, and osteogenic and may be able to promote bone healing for load-bearing applications.
authors.affiliation: Institute of Oral Biology and Biomaterials Science, Chung Shan Medical University, Taichung City 402, Taiwan. sjding@csmu.edu.tw
authors.forename: Shinn-Jyh
authors.initials: SJ
authors.lastname: Ding
authors.forename: Ming-You
authors.initials: MY
authors.lastname: Shie
authors.forename: Chung-Kai
authors.initials: CK
authors.lastname: Wei
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D016025:Bone Transplantation; D017610:Calcium Compounds; D002460:Cell Line; D049109:Cell Proliferation; D002478:Cells, Cultured; D055598:Chemical Phenomena; D005780:Gelatin / Q000737:chemistry*; D015870:Gene Expression; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D010012:Osteogenesis; D053495:Osteopontin / Q000235:genetics / Q000378:metabolism; D016062:Porosity; D017640:Silicates / Q000737:chemistry; D016474:Weight-Bearing
chemical_list: D001672:Biocompatible Materials; D017610:Calcium Compounds; D017640:Silicates; D053495:Osteopontin; D016753:Interleukin-10; D005780:Gelatin