ABSTRACT
The aim of the present study was to evaluate the biocompatibility and bone mineralization potential of 45S5 Bioglass-derived glass-ceramic scaffolds using a chick embryo shell-less (ex ovo) culture system. Chick embryos were divided into two groups: control (C) and experimental (E). Scaffolds were placed on the chorioallantoic membrane (CAM) in embryos of group E at 10 days of total incubation. The 45S5 Bioglass-derived glass-ceramic scaffolds proved to be biocompatible in terms of the absence of inflammatory response at the implant site (CAM). Moreover, no alterations in the other end-points assessed, i.e. survival, stage of embryonic development and body weight, were detected. However, body length was greater in group E embryos than in group C embryos (p0.05). A marked reduction (93%) in Ca content in the scaffolds was evidenced by energy-dispersive X-ray analysis at 5 days post-implantation. Calcium release from the scaffold implanted on the CAM might have been responsible for the restoration of the bone-like phenotype in chick embryonic skeleton of group E as detected by Alcian blue-Alizarin red double staining, as well as by histological and microchemical analyses. Conversely, the control embryos exhibited a chondrogenic phenotype.
Subject(s)
Biocompatible Materials/chemistry , Bone Substitutes/chemistry , Ceramics/chemistry , Alcian Blue/chemistry , Animals , Anthraquinones/chemistry , Calcium/chemistry , Chick Embryo , Inflammation , Ions , Materials Testing , Phenotype , Tissue Engineering/methods , X-RaysABSTRACT
The aim of the present study was to characterize the neoformed bone tissue around boron-modified bioactive glass particles implanted in rat tibia bone marrow by histologic, histomorphometric and microchemical evaluation. Melt-derived glasses were prepared from a base 45S5 bioactive glass of nominal composition (45% SiO(2), 24.5% CaO, 24.5% Na(2)O and 6% P(2)O(5) in wt%). The glass composition was modified by adding 2% wt of boron oxide (45S5.2B). Histological and histomorphometric analyses using undecalcified sections showed that at 15 days post-implantation the area of neoformed bone tissue around the 45S5.2B particles was significantly higher than control 45S5 glass. No statistically significant differences were observed at 30 days post-implantation. The thickness of osseointegrated tissue on 45S5.2B BG particles was significantly greater than on the control at all experimental time-points evaluated. A statistically significant increase in the Ca:P ratio was observed in the neoformed bone around 45S5.2B particles 15 days post-implantation. The results of the present study provide evidence that particles of boron-modified 45S5 BG (45S5.2B) enhance bone formation more than 45S5 glass when implanted into the intramedullary canal of rat tibiae.
