Negative Effect of Rapidly Resorbing Properties of Bioactive Glass-Ceramics as Bone Graft Substitute in a Rabbit Lumbar Fusion Model

이재협,유현승,Jun-Hyuk Seo,이도윤,장봉순,이춘기 대한정형외과학회 2014 Clinics in Orthopedic Surgery Vol.6 No.1

Background: Bioactive glass-ceramics have the ability to directly bind to bones and have been widely used as bone graft substitutes due to their high osteoconductivity and biocompatibility. CaO-SiO2-P2O5-B2O3 glass-ceramics are known to have good osteoconductivity and are used as bone graft extenders. Methods: This study aimed to evaluate the effects of the resorbing properties of glass-ceramics in bone fusion after producing and analyzing three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with high osteoconductivity that had enhanced resorption by having an increased B2O3 content. The three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with B2O3 contents of 8.0, 9.0, and 9.5 weight % were designated and grouped as P20B80, P10B90, and P5B95, respectively. Glass-ceramic types were tested for fusion rates and bone formation by employing the lumbar 5–6 intertransverse process fusion model in 51 New Zealand male rabbits. Bioactivity was assessed by soaking in simulated body fluid (SBF). Results: In vitro study results showed sufficient hydroxycarbonate apatite layer formation occurred for P20B80 in1 day, for P10B90 in 3 days, and for P5B95 in 5 days after soaking in SBF. For the rabbit lumbar spine posterolateral fusion model, the autograft group recorded a 100% fusion rate with levels significantly higher than those of P20B80 (29.4%), P10B90 (0%), and P5B95 (14.3%), with high resorbing properties. Resorbing property differences among the three glass-ceramic groups were not significant. Histological results showed new bone formation confirming osteoconductivity in all three types of glass-ceramics. Radiomorphometric results also confirmed the resorbing properties of the three glass-ceramic types. Conclusions: The high resorbing properties and osteoconductivity of porous glass-ceramics can be advantageous as no glass-ceramics remain in the body. However, their relatively fast rate of resorption in the body negatively affects their role as an osteoconductive scaffold as glass-ceramics are resorbed before bony fusion.

Treatment of Bone Defects in Rabbit Tibiae using CaO-SiO2-P2O5-B2O3 Bioactive Ceramics: Radiological, Biomechanical, and Histological Evaluation

( Ki Hyoung Koo ),( Chang Ju Hwang ),( Jae Hyup Lee ),( Bong Soon Chang ),( Choon Ki Lee ) 한국조직공학·재생의학회 2009 조직공학과 재생의학 Vol.6 No.4

Many calcium phosphate ceramics have been developed as bone graft substitutes to treat bone defect. Bioactive glass ceramics have been improved in terms of mechanical strength and bioabsorbance. The purpose of this study was to compare bone binding capacity of hydroxyapatite and bioactive ceramics made by CaO-SiO2-P2O5-B2O3(Bonglass 6, 7). Bioactive ceramics(Bonglass 6, 7) or hydroxyapatite plates of 5 mm height were inserted to tibial bony defect of New Zealand white rabbits weighing 3-3.5 kg. Total number of rabbits was 36 and divided into 3 groups randomly. Bony binding and fusion capacity were evaluated through the radiological study every 2 weeks. 12 weeks after surgery gross examination, manual palpation, biomechanical and histological studies were made. Seven rabbits in all group died during breeding but in autopsy finding, there was no evidence suggesting infection or graft rejection. Fusion rates were 77.8%(7/9) in Bonglass 6 group , 80%(8/10) in Bonglass 7group, and 70%(7/10) in hydroxyapatite group. Mean values of the tensile strengths were 126.3 ± 74.6 N in Bonglass 6 group , 136.6 ± 77.2 N in Bonglass 7 group, and 135.6 ± 113 N in hydroxyapatite group. In histological analysis of 2 specimens from each group, porous hydroxyapatite group showed slightly better bone binding capacity. Bonglass and hydroxyapatite group showed similar bone binding capacity and there was no statistically significant difference between 3 groups.

Quantitative Comparison of Novel CaO-SiO2-P2O5-B2O3 Glass-Ceramics (BGS-7) with Hydroxyapatite as Bone Graft Extender in Rabbit Ilium

( Jae Hyup Lee ),( Ul Oh Jeung ),( Do Hwan Jeon ),( Bong Soon Chang ),( Choon Ki Lee ) 한국조직공학과 재생의학회 2010 조직공학과 재생의학 Vol.7 No.5

Bioactive glass-ceramics are known to have osteoconductivity and good mechanical properties. The purpose of this study was to evaluate the osseointegrative characteristics of CaO-SiO2-P2O5-B2O3 glass-ceramics (BGS- 7) and HA quantitatively. Seventy-two BGS-7, titanium, PEEK, and HA implants were inserted into the iliums of 72 New Zealand white male rabbits. The biomechanical and histomorphometric analysis was performed. Mean tensile force of BGS-7 was significantly higher than those of titanium and PEEK at 2 and 4 weeks postoperatively and significantly higher than the other three implants at 8 weeks postoperatively. The mean tensile force of HA was also significantly higher than those of titanium and PEEK at 2 and 8 weeks. Histologic evaluations showed broad-based bone bonding to HA and BGS-7 and histomorphometric analysis of the bone-to-implant contact percentages of BGS-7 and HA for all observation periods were significantly higher than those of titanium or PEEK. These findings suggest that BGS-7 promotes bone bonding and that it may be considered as a possible bone graft extender.

Effects of Bisphosphonate-Treated Bioactive Ceramic Grafts for the Proliferation and Osteoblastic Differentiation of Human Bone Marrow Mesenchymal Stem Cells

( Jae Hyup Lee ),( Kyung Mee Lee ),( Soo Jeong Jang ),( Hye Soo Lee ),( Hae Ri Baek ) 한국조직공학·재생의학회 2011 조직공학과 재생의학 Vol.8 No.1

Bisphosphonates have been reported to accelerate osteoblastic differentiation of human mesenchymal stem cells, and bioactive glass-ceramics have been used as bone graft extender due to high osteoconductivity. The purpose of this study is to find out what effects CaO-SiO2-P2O5-B2O3 glass-ceramics (BGS-7) treated with alendr-onate have on the osteoblastic differentiation of human mesenchymal stem cells. Human bone marrow mesenchymal stem cells cultured on BGS-7, hydroxyapatite and cell plate are treated with different concentrations of alendronate and analyzed by MTS assay, ALP assay, RT-PCR, western blot analysis and SEM. The result of the MTS assay shows that the OD value was highest in BGS-7, followed by HA and the plate, and the ALP assay shows that the OD value was higher in the BGS-7 group than the plate group when treated with 10-7 M alendronate. According to the RT-PCR analysis, osteopontin had higher expression in the alendronate-treated group than the non-treated group upon one-week differentiation, showing a clear increase in BGS-7, and osteocalcin and runx-2 showed enhanced expression in the BGS-7 group treated with 10-7M alendronate during week 3 of differentiation. Also, in the western blot analysis, the expression of osteocalcin and runx-2 was increased in the BGS-7 group compared to the plate group in terms of protein expression. The SEM assay shows that the presence of osteoblasts was more evident and the mineral content was higher in the alendronate-treated BGS-7 group than in the alendronate-non treated BGS-7 and alendronate-treated HA. When treated with alendronate, BGS-7, HA and cell plate all accelerated the osteoblastic differentiation of human bone marrow mesenchymal stem cells and especially, the osteoblastic differentiation was accelerated even more in CaO-SiO2-P2O5-B2O3 glass-ceramics (BGS-7) than hydroxyapatite.

Synthesis and characterization of silk fibroin-bioactive glass hybrid xerogels

Wu, Xiaohong,Yan, Fuhua,Liu, Wei,Zhan, Hongbing,Yang, Wenrong Techno-Press 2014 Biomaterials and Biomechanics in Bioengineering Vol.1 No.2

This study aimed to develop a novel bioactive hybrid xerogel consisting of silk fibroin /$SiO_2-CaO-P_2O_5$ by sol-gel process at room temperature. Scanning electron microscopy (SEM), FT-IR Spectroscopy, pore measurement, mechanical property testing, in vitro bioactivity test and cytotoxicity assay were performed to characterize the xerogel for bone tissue engineering application. We have found that the xerogel possessed excellent pore structures and mechanical property. Once immersed in a simulated fluid (SBF), the xerogel exhibited profound bioactivity by inducing hydroxyapatite layers on its surfaces. The cell toxicity study also demonstrated that there was little toxic to MC3T3-E1 cells. These results indicate that silk fibroin /$SiO_2-CaO-P_2O_5$ hybrid xerogel potentially could be used as a bone tissue engineering material.

Synthesis and characterization of silk fibroin-bioactive glass hybrid xerogels

Wu, Xiaohong,Yan, Fuhua,Liu, Wei,Zhan, Hongbing,Yang, Wenrong Techno-Press 2014 Biomaterials and biomedical engineering Vol.1 No.2

This study aimed to develop a novel bioactive hybrid xerogel consisting of silk fibroin /$SiO_2-CaO-P_2O_5$ by sol-gel process at room temperature. Scanning electron microscopy (SEM), FT-IR Spectroscopy, pore measurement, mechanical property testing, in vitro bioactivity test and cytotoxicity assay were performed to characterize the xerogel for bone tissue engineering application. We have found that the xerogel possessed excellent pore structures and mechanical property. Once immersed in a simulated fluid (SBF), the xerogel exhibited profound bioactivity by inducing hydroxyapatite layers on its surfaces. The cell toxicity study also demonstrated that there was little toxic to MC3T3-E1 cells. These results indicate that silk fibroin /$SiO_2-CaO-P_2O_5$ hybrid xerogel potentially could be used as a bone tissue engineering material.