Biological effects of calcium sulfate as a bone graft substitute in ovine metaphyseal defects

Calcium sulfate has been used as a bone graft substitute in many fields, from dentistry to orthopedics. However, the results of many studies have yielded inconclusive results. In the present study, a sheep model was used with tibial and femoral metaphyseal defects to determine whether calcium sulfate was as effective as autograft and allograft in promoting new bone formation in a critical size defect. Medical-grade calcium sulfate pellets, autograft bone, allograft bone, or nothing was used to fill the metaphyseal defects. The sheep were allowed to heal for 12 weeks. Sagittal sections from the bones were analyzed with high-resolution contact radiographs, backscattered electron microscopy, and light microscopy. The volume fractions of bone within the defect perimeter were determined, and the histologic quality of the bone was observed. The volume fraction of new bone in the autograft, calcium sulfate, and allograft were not statistically different, but all were significantly different than the untreated control. The majority of the calcium sulfate had been resorbed at 12 weeks, and the histologic quality of the bone appeared similar to the autograft-treated bone. Calcium sulfate appears to be a useful biocompatible bone graft substitute that yields results similar to autograft bone in sheep metaphyseal defects.     

全髋翻修髋臼骨缺损中颗粒打压植骨的应用

背景：髋臼重建植骨分为颗粒植骨、结构植骨和混合植骨,而颗粒骨由于制作简便、愈合时间短等优点而被大量使用。 目的：探讨全髋人工关节翻修中髋臼AAOSIII型骨缺损颗粒打压植骨技术的应用要点和临床效果。 方法：16例髋关节翻修AAOSIII骨缺损患者采用单纯颗粒打压植骨技术、结合金属器械或结构植骨处理髋臼AAOSIII型骨缺损。对比治疗前及治疗后定期随访的髋关节Harris评分及影像学资料,评估颗粒打压植骨对该型髋臼骨缺损的治疗效果。 结果与结论：按照治疗后3,6,12个月及每半年周期随访中,16例患者髋关节疼痛症状均得到明显缓解,并恢复行走功能。16例患者治疗后Harris髋关节功能评分由治疗前平均48.00分提高到84.94分(P < 0.01),其中优5例,良8例,可2例,差1例,优良率为81%,患者满意率为94%。16例患者术后X射线片示髋臼旋转中心均恢复(接近)正常,臼杯骨性覆盖良好,植骨颗粒获得放射学骨整合,臼杯假体未发生移位,假体植入物未发生位置改变或断裂现象。结果提示颗粒打压植骨技术修复翻修髋臼AAOSIII型骨缺损,有效重建了髋臼的骨性结构,保留并恢复了髋臼的骨量,具有良好的技术优势和临床疗效。     

自体骨髓移植复合人工骨治疗骨缺损

背景：到目前为止,国内人工骨联合自体骨髓移植治疗新鲜骨折、骨缺损方面的基础与临床研究尚未见报道。 目的：分析自体骨髓移植复合人工骨修复四肢粉碎性骨折骨缺损的作用途径。 方法：42例四肢骨缺损患者按治疗方法分为3组,均采用内固定方法修复骨折骨缺损。复合组采用自体骨髓移植复合人工骨,人工骨移植组仅作单纯的人工骨移植,自体骨髓移植组仅将单纯的自体骨髓注射入骨缺损处。所有患者均行骨特异性碱性磷酸酶活性检测和影像学随访,观察骨痂形成及骨折愈合情况。 结果与结论：在内固定后第3,4,6周,复合组伤肢骨痂形成率、骨特异性碱性磷酸酶活性均显著高于人工骨移植组及自体骨髓移植组(P < 0.01)。提示自体骨髓移植复合人工骨较单纯的人工骨移植或自体骨髓移植更能促进早期骨痂反应,加速骨折后骨缺损愈合,缩短骨愈合时间及住院时间。     

Behaviour of tricalcium phosphate and hydroxyapatite granules in sheep bone defects

Granules of hydroxyapatite (HA) and tricalcium phosphate (TCP) were implanted in separate holes drilled in mandibular bone of sheep to check the bone growth and in vivo behaviour of the materials. The experiment was performed in three sheep, killed respectively at 4, 8, 12 month. Samples of bone with the materials were explanted, microradiographed and sectioned to evaluate the interface under optical and electron scanning electron microscope. The hole, left empty as a reference, showed no full repair; whereas 4 month after implantation the TCP granules induce total repair of the hole. HA granules crumbled and no new bone induction was seen even 12 month after implantation.     

自体微小颗粒骨植骨混合万古霉素开放性植骨修复感染性胫骨缺损

背景：研究发现直径300-500 μm微米结构的微小颗粒骨比直径4.0-5.0 mm的经典颗粒骨更容易在非感染骨缺损中成活。 目的：评价采用自体微小颗粒骨植骨混合万古霉素开放性植骨修复感染性胫骨骨缺损的可行性及临床效果。 方法：选择28例胫骨感染性骨缺损或骨不连患者,其中男23例,女5例,平均年龄35.2岁;胫骨上段19例,胫骨中段2例,胫骨下段7例;开放性骨折术后感染病例17例,骨折术后感染合并骨不连11例。随访6-30个月观察创面及骨折愈合情况。 结果与结论：术后平均6周移植微小颗粒骨表面被肉芽组织覆盖,平均8周创面完全闭合,经植骨后骨缺损处均骨性愈合,2例骨折愈合差,经二次植骨后达到骨性愈合,平均愈合时间5个月。未发生神经血管损伤及药敏反应。表明自体微小颗粒骨植骨混合万古霉素开放性植骨修复治疗感染性胫骨缺损是可行的。     

Biological and mechanical enhancement of impacted allograft seeded with human bone marrow stromal cells: potential clinical role in impaction bone grafting

With the demographics of an aging population the incidence of revision surgery is rapidly increasing. Clinical imperatives to augment skeletal tissue loss have brought mesenchymal stem cells to the fore in combination with the emerging discipline of tissue engineering. Impaction bone grafting for revision hip surgery is a recognized technique to reconstitute bone, the success of which relies on a combination of mechanical and biological factors. The use of morsellized allograft is currently the accepted clinical standard providing a good mechanical scaffold with little osteoinductive biological potential. We propose that applying the principles of a tissue engineering paradigm, the combination of human bone marrow stromal cells (hBMSCs) with allograft to produce a living composite, offers a biological and mechanical advantage over the current gold standard of allograft alone. This study demonstrates that hBMSCs combined with allograft can withstand the forces equivalent to a standard femoral impaction and continue to differentiate and proliferate along the bony lineage. In addition, the living composite provides a biomechanical advantage, with increased interparticulate cohesion and shear strength when compared with allograft alone.     

大块异体骨联合自体骨髓移植修复股骨上段肿瘤切除后缺损

背景：由于骨肿瘤切除造成的骨组织缺损是临床面临的难题之一,而如何修复缺损是骨科领域的热点问题。 目的：探讨采用大块异体骨联合自体骨髓移植治疗股骨上段肿瘤的临床应用及疗效。 方法：于2000-07/2005-06采用辐照冻存的大块异体骨联合自体骨髓移植治疗股骨上段良性肿瘤切除后遗留大块骨缺损12例,手术采用类似脊柱的“蛋壳”技术,掏空股骨头,保留股骨头圆韧带及头的皮质骨,尽量保留股骨头的1/3的血供,应用大块异体骨联合自体骨髓移植加内固定治疗。 结果与结论：患者术后随访6~11年。术后所有12例患者的大块异体骨联合自体骨髓在X射线中均显示整合血管化良好,骨小梁通过自体骨。MSTS93总体平均评分为26.33分,患者肢体功能总的优良率为83.3%。提示大块异体骨联合自体骨髓移植是修复股骨上段肿瘤切除后骨大块缺损的有效方法,并能充分整合成周围的自体骨。     

可注射型人工骨与异体松质骨治疗骨质疏松性胫骨平台Schatzker Ⅱ型骨折的植骨效果比较

目的比较可注射型人工骨与异体松质骨治疗骨质疏松性胫骨平台Schatzker Ⅱ型骨折的植骨效果。方法2015年8月至2017年3月解放军第180医院骨科共收治43例骨质疏松性胫骨平台Schatzker Ⅱ型骨折患者。所有病人随机分为两组,其中治疗组17例,应用Genex-S慢凝型可注射型人工骨进行胫骨平台关节面下注射植骨;对照组26例,应用异体松质骨关节面下填压植骨。分别在术后1周内、术后3个月、术后6个月与术后12个月进行膝关节正侧位X线片及植骨区域骨密度检查,记录胫骨外髁关节面塌陷高度、膝关节外侧间隙高度、外侧间隙角、植骨区域骨密度。结果治疗组术后12个月胫骨外髁关节面总体塌陷高度(1.8 mm±0.7 mm)、外侧间隙总体丢失高度(0.20 mm±0.10 mm)与外侧间隙角总体增加角度(4.62°±0.41°)均小于对照组(8.4 mm±1.7 mm,0.20 mm±0.10 mm,4.62°±0.41°),差异有统计学意义(P0.01)。治疗组各时间点植骨区域骨密度T值均高于对照组,差异均有统计学意义(P0.01)。结论在骨质疏松性胫骨平台Schatkzer Ⅱ型骨折的治疗中,可注射型人工骨的植骨强度与稳定性优于异体松质骨,可能是一种适用于骨质疏松性骨折支撑植骨的良好生物填充材料。     

Establishment and effects of allograft and synthetic bone graft substitute treatment of a critical size metaphyseal bone defect model in the sheep femur

Assessment of bone graft material efficacy is difficult in humans, since invasive methods like staged CT scans or biopsies are ethically unjustifiable. Therefore, we developed a novel large animal model for the verification of a potential transformation of synthetic bone graft substitutes into vital bone. The model combines multiple imaging methods with corresponding histology in standardized critical sized cancellous bone defect. Cylindrical bone voids (10 ml) were created in the medial femoral condyles of both hind legs (first surgery at right hind leg, second surgery 3 months later at left hind leg) in three merino‐wool sheep and either (i) left empty, filled with (ii) cancellous allograft bone or (iii) a synthetic, gentamicin eluting bone graft substitute. All samples were analysed with radiographs, MRI, μCT, DEXA and histology after sacrifice at 6 months. Unfilled defects only showed ingrowth of fibrous tissue, whereas good integration of the cancellous graft was seen in the allograft group. The bone graft substitute showed centripetal biodegradation and new trabecular bone formation in the periphery of the void as early as 3 months. μCT gave excellent insight into the structural changes within the defects, particularly progressive allograft incorporation and the bone graft substitute biodegradation process. MRI completed the picture by clearly visualizing soft tissue ingrowth into unfilled bone voids and presence of fluid collections. Histology was essential for verification of trabecular bone and osteoid formation. Conventional radiographs and DEXA could not differentiate details of the ongoing transformation process. This model appears well suited for detailed in vivo and ex vivo evaluation of bone graft substitute behaviour within large bone defects.     

Morsellised sawbones is an acceptable experimental substitute for the in vitro elastic and viscoelastic mechanical characterisation of morsellised cancellous bone undergoing impaction grafting

Impaction grafting using morsellised bone chips is widely used during surgery to mitigate the effects of bone loss. The technique typically involves the packing of morsellised allograft cancellous bone into bone defects, and has found extensive application in revision hip and knee surgery. In the ideal situation, the presence of the bone graft prevents subsidence of the revised prosthesis in the short term, and integrates with the host bone in the longer term. However, the configuration of particles within the graft remains to be optimised, and is highly likely to vary across potential sites and loading conditions. Human bone, for use in experimental investigation, is often difficult to obtain with properties that are relevant from a clinical point of view. This study, therefore, has explored the mechanical response of a Sawbones based experimental substitute. An established confined compression technique was used to characterise the morsellised Sawbones material. Comparison of the results with published values for bovine and human bone indicate that the mechanical response of the morsellised Sawbones material map well onto the elastic and viscoelastic response of bone of a biological origin.     

Micromelic dwarfism with cone epiphyses,metaphyseal dysplasia,and vertebral segmentation defects

We present the clinical and radiological findings in a newborn male with severe micromelic dwarfism, short neck, short and narrow upper thorax, and brachydactyly. At the age of 1 year mental development is slightly retarded. The X-ray findings of severe vertebral segmentation defects and a generalized metaphyseal skeletal dysplasia did not lead to a final, conclusive diagnosis. The present patient may be the first example of a new type of micromelic spondyloepi-metaphyseal dysplasias. © 1996 Wiley-Liss, Inc.     

Bone regeneration within a tailor-made tricalcium phosphate bone implant with both horizontal and vertical cylindrical holes transplanted into the skull of dogs

A new tailor-made bone implant (TI) with six horizontal cylindrical holes fabricated from α-tricalcium phosphate powder, as described in our previous report, was modified to include five additional vertical holes (TI-v) in an attempt to accelerate the bone regeneration through the holes. This TI-v implant and hydroxyapatite implants (HI) as controls were transplanted into experimental skull defects in dogs. Computed tomography (CT) was performed immediately after the surgery and then every 4 weeks. The dogs were killed for histological analysis at 24 weeks of implantation. On CT, bone bridging between the implant and the skull was observed in the TI-v group from 8 weeks of implantation, whereas a clear bone bridge was not formed in the HI group after 24 weeks of implantation. Histological analysis revealed collagen tissues and new bone formation in the horizontal cylindrical holes in most of the TI-v group, whereas mainly connective tissues invaded the porous structures in the HI group. In the Ti-v group, at the middle of the horizontal holes where they crossed the vertical holes, fibrous collagen tissues and muscular tissue filled up the hole and new bone formation seemed to be blocked. However, in the TI-v group more collagen and bone tissues were formed than in the HI group; when compared with the data in our previous report, however, the total volume of regenerated bone in the horizontal cylindrical holes in the TI-v seemed to be less than that in the TI. Thus, the addition of vertical cylindrical holes in the TI-v was not effective in promoting the faster stabilization of the TI-v in the skull of the dog.     

Examination of osteoarthritis and subchondral bone alterations within the stifle joint of an ovariectomised ovine model

The exact relationship between osteoporosis and osteoarthritis is still a matter for debate for many. The ovariectomised ewe is frequently used as a model for osteoporosis, resulting in significant alterations in bone morphometry and turnover in both trabecular and subchondral bone after 1 year. This study examines whether ovariectomy has any impact on development of osteoarthritis within the ovine stifle joint at the same time point. In addition, we investigate whether there are any significant correlations present between articular cartilage degeneration and alterations in microstructural parameters or turnover rates in the underlying bone. Twenty‐two sheep were examined in this study; 10 of the sheep underwent ovariectomy and 12 were kept as controls. Five distinctive fluorochrome dyes were administered intravenously at 12‐week intervals to both groups, to label sites of bone turnover. All animals were then sacrificed 12 months postoperatively. Although most specimens showed some evidence of osteoarthritis, no measurable difference between the two study groups was detected. Osteoarthritis was associated with a thinning of the subchondral plate, specifically the subchondral cortical bone; however, whereas previous studies have suggested a link between trabecular thinning and osteoarthritis, this was not confirmed. No correlation was found between osteoarthritis and bone turnover rates of either the subchondral trabecular bone or bone plate. In conclusion, despite the fact that ovariectomy results in marked morphological and structural changes in the ovine stifle joint at 1‐year postoperatively, no evidence was found to suggest that it plays a direct role in the aetiology of osteoarthritis.     

Unclassified sclerosing bone dysplasia with osteopathia striata,cranial sclerosis,metaphyseal undermodeling,and bone fragility

Sclerosing bone dysplasias are diagnosed on the basis of a characteristic pattern of osteosclerosis and clinical manifestations; in many of them, cause and pathogenesis are still unknown. A 33-year-old man had five fractures of the humerus, tibiae, and femur as a result of mild traumatic incidents that occurred between the ages of 18 and 33 years as well as a remnant of rib fractures without apparent trauma on radiographs. His height was 158 cm (−2.2 SD). Radiographic evaluation showed cranial sclerosis, longitudinal striations in the metaphyses of the femur and tibia, fan-like striation in the ilium, metaphyseal widening in the femur and tibia, and sclerosis of the ribs. The blood chemistry findings, including serum calcium, phosphorus, and alkaline phosphatase, were normal. Biopsy from the ilium showed thick trabeculae composed of woven bone. The coexistence of osteopathia striata, cranial sclerosis, metaphyseal undermodeling, and bone fragility has not been recognized previously. Our case appears to represent a new form of sclerosing bone dysplasia. Am. J. Med. Genet. 76:389–394, 1998. © 1998 Wiley-Liss, Inc.     

引导组织再生联合植骨修复根分叉病变的Meta分析

BACKGROUND: Numerous experimental and clinical observations have shown new attachment formation in the periodontium by guided tissue regeneration. OBJECTIVE: To evaluate the efficacy of guided tissue regeneration combined with bone grafting for the treatment of root furcation defects. METHODS: A computer-based online search combined with manual retrieval was conducted up to 2015 to screen the relevant English and Chinese literatures addressing guided tissue regeneration, bone grafting, and root furcation defects. Vertical and horizontal probing depth and attachment loss were analyzed. Meta-analysis was performed using Stata/SE version 12.0 software by extracting data from the relevant articles. Moreover, the publication bias was tested. RESULTS AND CONCLUSION: The meta-analysis results showed that at 6 months after treatment, the alterations in vertical probing depth and periodontal attachment were significantly increased after guided tissue regeneration compared with open-flap debridement (P < 0.000 01); the alterations and increment in the periodontal attachment were significantly increased after combined treatment of guided tissue regeneration and bone grafting compared with open-flap debridement (P < 0.000 01); the reduction in the vertical and horizontal probing depth and the increment in periodontal attachment were significantly increased after combined treatment of guided tissue regeneration and bone grafting compared with guided tissue regeneration (P < 0.000 01 or P = 0.01). At 12 months after treatment, the reduction in vertical probing depth and the increment in attachment loss were significantly increased after combined treatment of guided tissue regeneration and bone grafting compared with guided tissue regeneration (P < 0.000 01). These results indicate that the guided tissue regeneration combined with bone grafting in the treatment of root furcation defects is superior to guided tissue regeneration or open-flap debridement. In addition, in the latter two therapies, guided tissue regeneration shows a better therapeutic effect. However, the therapeutic effects of various types of regenerated membranes and bone grafts need further in-depth study to define the optimal treatment strategy. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

The effect of licochalcone A on cell-aggregates ECM secretion and osteogenic differentiation during bone formation in metaphyseal defects in ovariectomized rats

Treatment of weight-bearing bones fractures with defects is critical for patients with osteoporosis's rehabilitation. Although various tissue engineering methods were reported, the best treating strategy for tissue engineering remains to be identified as the limitation of enhancing the ability of the osteogenetic differentiation potential of seed cell is one of the cardinal issues to be solved. The objective of this study is to investigate the feasibility of applying licochalcone-A (L-A) and bone marrow mesenchymal stem cells (BMSC)-aggregate in bone repairing tissue engineering and further study the biological effects of L-A on the cell aggregate formation and osteogenic properties. 80 female Sprague Dawley rats underwent bilateral ovariectomy were made with a 3.5 mm femurs bone defects without any fixation. These rats were then randomly assigned to five different treatment groups: (1) empty defect (n = 16), (2) CA-LA (n = 16), (3) CA-N (n = 16), (4) CA-L (n = 16), (5) CA-S (n = 16) and 16 female SD rats were treated as a control. Data showed that L-A administrated cell aggregate had a stronger osteogenic differentiation and mineralized formation potential than non-administrated group both in vitro and in vivo. For in vitro study, L-A administrated group had a more significant expression of ECM, osteogenic associated maker in addition with more mineralized area and higher ALP activity compared with the control group. For in vivo study, 3D reconstruction of micro-CT, HE staining and bone strength results showed that newly formed bone in groups administrated by L-A was significant higher than that in Sham group at 2, 4, 8 and 12 weeks after transplantation, especially for groups which was systematically injected with L-A at 8 weeks. Results of our study demonstrated that LA could positively affect cell behavior in cell-aggregate engineering and could be a promising strategy in treating osteoporotic weight-bearing bones fractures with defects.     

异种煅烧骨材料修复骨缺损：特点、优势与问题

文题释义： 拔牙位点保存：当由于各种原因拔除牙齿后,其周围的牙槽骨在前6个月将会发生水平向和垂直向上的严重吸收,导致种植手术时骨量不足,严重影响种植修复的成功率。许多学者建议在彻底拔除牙齿的同时,于拔牙窝内放置骨粉和骨膜进行保护和修复性干预,将会显著减少周围牙槽嵴生理或病理性的骨吸收、阻断周围龈缘和龈乳头的退缩,保存牙槽窝周围软硬组织的高度和形态,并改善新生软硬组织的质量,为后期的种植美学修复创造良好条件。 爬行替代：在具有良好血供的骨损伤区域植入骨移植材料后,将会激活骨再生程序：破骨细胞开始活动,并在植骨材料上进行骨吸收,形成一条条“沟”状缺损,引导骨原细胞进入,随之分化为成骨细胞,成骨细胞分泌大量的类骨质,钙化成骨基质,成熟为骨单位。即在骨移植材料逐渐吸收的部位新生骨组织逐渐形成,充填骨吸收的凹陷。 背景：牙种植区域的牙槽骨骨量不足增加了种植手术难度,植骨材料的出现成功解决了此类难题。在所有单一植骨材料中,异种煅烧骨被广泛用于治疗骨缺损,但单独使用煅烧骨时仍然存在一些缺点。 目的：结合最新的相关研究动态,对异种煅烧骨材料修复骨缺损的相关研究进展作以综述。 方法：第一作者以“calcined bone,xenogeneic bone,bone augmentation,bone substitute”为英文检索词,以“煅烧骨、异种骨、骨增量、骨替代材料”为中文检索词,应用计算机检索 PubMed、维普、万方、知网数据库中1986年1月至2019年11月已发表的相关文献,并进行筛选、归纳与总结,最终纳入69篇相关文献进行综述。 结果与结论：在所有骨移植材料中,异种煅烧骨的结构与人类骨骼相似,具有良好的互连孔性,便于血管因子和骨原细胞进入,为新骨形成提供了通道和支架作用,同时具有良好的生物相容性及一定的降解作用,受到临床医生们的青睐。但其本身仍然存在溶解度较低、吸收缓慢、机械性能较差等不足,这就促使研究者们研发出将煅烧骨与陶瓷、聚合物、骨诱导因子及金属离子等其他材料复合,发挥出所参与材料的优点,从而使复合材料成为骨增量材料的首选。 ORCID: 0000-0002-0313-7462(李芳) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

Freeze-dried and irradiated allograft bone combined with fresh autologous coagula promotes angiogenesis in an ectopic bone allograft implantation model

Background: Freeze-dried and irradiated allograft bone (FIAB) is more easily impacted than fresh-frozen allograft bone (FAB), but has weaker incorporation efficiency. We combined FIAB with fresh autologous coagula to enhance donor-host incorporation after impaction during hip revision. Methods: Thirty adult male Sprague–Dawley (SD) rats were sacrificed for bone allograft harvesting, and nine male rats were subjected to ectopic bone allograft implantation. For each rat, the container on the left (study) side was filled with freeze-dried allograft bone powder and fresh autologous blood coagula, whereas the right (control) side was filled with freeze-dried allograft bone powder and physiological saline. The extent of angiogenesis (VEGFα) was investigated at postoperative weeks 1, 4, and 8. The deformability of the material was evaluated by performing a confined-impaction mechanical test. Results: At postoperative weeks 4 and 8, angiogenesis within FIAB on the left side was more pronounced than that on the right side. At postoperative week 1, the left side showed significantly higher VEGFα expression than that on the right side. The delta ratios of compression of the allografts were found to be influenced by bone height and impaction frequency, but not by stiffness or elastic modulus (EM). Conclusion: Supplementation with fresh autologous coagula promoted angiogenesis within the FIABs. Moreover, FIABs were equivalent to FABs in terms of deformability.     

Effect of adipose tissue-derived osteogenic and endothelial cells on bone allograft osteogenesis and vascularization in critical-sized calvarial defects

The use of processed bone allograft to repair large osseous defects of the skull has been limited, given that it lacks the osteogenic cellularity and intrinsic vascular supply which are essential elements for successful graft healing and, at the same time, the areas to be targeted through tissue-engineering applications. In this study, we investigated the effect of predifferentiated rat adipose tissue-derived osteoblastic cells (OBs) and endothelial cells (ECs) on calvarial bone allograft healing and vascularization using an orthotopic critical-sized calvarial defect model. For this purpose, thirty-seven 8?mm critical calvarial defects in Lewis rats were treated with bone allografts seeded with no cells, undifferentiated adipose tissue-derived stem cells (ASC), OBs, ECs, and OBs and ECs simultaneously. After 8 weeks, the bone volume and mineral density were calculated using microcomputed tomography and the microvessel formation using immunohistochemical staining and imaging software. The amount of bone within the 8?mm defect was significantly higher for the allografts treated with ECs compared with the allografts treated with OBs (p=0.05) and simultaneously with the two cell lineages (p=0.02). There were no significant differences in bone formation between the latter two groups and the control groups (allografts treated with no cells and undifferentiated ASC). There were no significant differences in bone mineral density among the groups. The amount of microvessels was significantly higher in the group treated with ECs relative to all groups (p=相似文献   

Repair of segmental bone defects using bioactive bone cement: comparison with PMMA bone cement.

We developed a bioactive bone cement (BABC) that consists of apatite and wollastonite containing glass ceramic (AW-GC) powder and bisphenol-A-glycidyl dimethacrylate (Bis-GMA) based resin. In the present study, the effectiveness of the BABC for repair of segmental bone defects under load-bearing conditions was examined using a rabbit tibia model. Polymethylmethacrylate (PMMA) bone cement was used as a control. A 15-mm length of bone was resected from the middle of the shaft of the tibia, and the tibia was fixed by two Kirschner wires. The defects were replaced by cement. Each cement was used in 12 rabbits; six rabbits were sacrificed at 12 and 25 weeks after surgery, and the tibia containing the bone cement was excised and tension tested. At both the intervals studied, the failure loads of the BABC were significantly higher than those of the PMMA cement. The BABC was in direct contact with bone, whereas soft tissue was observed between the cement and bone in all PMMA cement specimens. Results indicated that the BABC was useful as a bone substitute under load-bearing conditions.