Relationship between bone mineral density and bone stiffness in bone fracture

Objectives Using cancellous bone blocks of racehorses, the relationship between bone mineral density (BMD), which indicates bone strength, and stiffness in bone fracture occurrences was studied.Methods Two groups of cancellous bone blocks were prepared: a fractured group, using the first phalangeal bones of seven racehorses with sagittal fractures; and a nonfractured group, using the first phalangeal bones of nine autopsied racehorses without any fractures. By a peripheral quantitative computed tomography scan, the BMD values were shown as color images and evaluated. In addition, the BMD values obtained from the fractured and nonfractured groups were compared with the stiffness values obtained from a compression test.Results The difference between the average BMD values of the fractured and nonfractured groups was easily observed on the BMD color-conversion display image. The average BMD of the fractured group (472.1 mg/cm³) was significantly higher than that of the nonfractured group (284.5 mg/cm³, P = 0.005). Moreover, the average stiffness of the fractured group (5564.5 N/cm) was significantly higher than that of the nonfractured group (3808.6 N/cm, P = 0.008).Conclusion These results suggest that the occurrence of a fracture does not depend on the BMD or the bone stiffness value.     

颌骨动脉瘤样骨囊肿的临床分析

目的：探讨颌骨动脉瘤样骨囊肿的临床表现、治疗方法及预后特点。方法收集8例颌骨动脉瘤样骨囊肿患者的临床资料,包括性别、年龄、病程、症状、影像学检查、治疗及预后等,并对患者的临床资料进行回顾性分析。结果8例患者中,女性5例,男性3例,年龄5～48岁;发生于上颌骨3例,下颌骨5例,均为原发性病变;颌骨CT扫描显示为多囊性膨胀性占位病变,内见分隔、残留骨嵴及液?液平面形成,增强后病灶周围可显示迂曲扩张的小血管影。所有患者均经病理检查明确诊断,光镜下观察,可见囊壁由梭形纤维细胞、组织细胞、破骨样多核巨细胞及慢性炎症细胞构成,呈飘带样结构,囊腔由含骨及类骨碎片的纤维组织分隔,见有出血及含铁血黄素沉积。8例患者均以病灶根治性切除为主要治疗手段。经1～6年的随访,均无复发。结论颌骨动脉瘤样骨囊肿的影像学表现具有其自身特点,确诊依靠病理诊断,治疗以病灶根治性切除为主。多数病例在病灶彻底切除后能够获得较好的预后。     

Crosstalk between cancer and bone microenvironment in bone metastasis

Bone is one of the most preferential target sites for cancers such as breast, prostate and lung cancers to metastasize.     

The effcct of eel bone powder on bone mineral density in mouse femoral bone

Improvement in bone mineral density (BMD) in the femur after administration of eel bone powder (EBP) was evaluated in ovariectomized (OVX) mice. Female ICR mice were given ovariectomies or sham operations at 9 weeks of age, then housed for 2 weeks during which they were allowed free access to a normal diet. Subsequently, the mice were divided into 3 groups: sham-operated mice fed a normal diet, OVX mice fed a normal diet, and OVX mice fed a diet containing EBP. After the mice in these 3 groups had been housed for 2 months (during which time they were allowed free access to their respective diets), they were dissected and analyzed. The BMD values in the removed femurs were measured by peripheral quantitative computed tomography (pQCT). Femoral total and femoral cancellous BMD values were higher in the EBP-treated group than in the nontreated group. Total BMD: the value in the EBP-treated group was 573 mg/cm³, and that in the non-treated group was 451 mg/cm³ (p<0.05). Cancellous BMD: the value in the EBP-treated group was 242 mg/cm³, and that in the non-treated group was 143 mg/cm³ (p<0.05). However, cortical BMD values did not significantly differ between the EBP-treated group and the non-treated group. Cortical BMD: The value in the EBP-treated group was 1891 mg/cm³, and that in the non-treated group was 1900 mg/cm³. pQCT was used to measure the cortical and cancellous BMD in the long bones. By use of a color conversion technique to display BMD, regional changes in the long bones can be expressed and easily measured. It has been well documented that EBP is effective for improvement or prevention of BMD reduction associated with OVX.     

骨替代材料在口腔种植领域中的成骨效果

骨替代材料目前已成为拔牙位点保存术、牙槽嵴骨增量术和上颌窦底提升术的主要材料,而羟磷灰石、磷酸钙和生物活性玻璃以其良好的生物相容性、骨传导性、生物降解性、骨再生能力和骨结合率成为骨替代材料的代表.单一成分骨替代材料的诱导骨再生能力取决于材料本身的表面形貌、结构、成分、孔径和孔隙率.按不同比例复合的新型骨替代材料,可使原单一骨替代材料的性能得以互补.骨替代材料与血小板浓缩物的联合应用,可促进前成骨细胞的增殖与分化,激发成骨细胞的活动,促进血管新生,从而利于骨替代材料存活.骨替代材料与生长因子的联合应用,可获得不同程度骨结合和骨改建,增加材料的细胞黏附率,改善支架的力学性能,在骨愈合早期即能促进新骨形成.随着科技的进步,未来骨替代材料的成骨性能日臻完善,在口腔种植领域的应用前景将会更加广阔.     

The effect of platelet-rich plasma combined with autogenous bone graft for bone regeneration in bone defects

The objective of the present study was to evaluate the effect of PRP on bone healing both quantitatively and qualitatively using histomorphometrical methods in a rabbit model. The examined materials were autogenous bone, PRP alone, a mixture of autogenous bone and PRP, and whole blood (as a control). These materials were implanted into artificial defects prepared in rabbit tibiae. The observation period was set at 1, 2, 3, and 4 weeks. All specimens were used for histologic evaluation and 2- and 4-week specimens were used for histomorphometrical evaluations. The bone quantity increased when autogenous bone was applied but the percentage of mature bone in the autogenous bone site was smaller than in the PRP applied site. The results of this study suggested that the quantity of newly formed bone increased when autogenous bone was applied, but not when PRP only was applied. However, PRP might accelerate bone maturation by activating bone remodeling. According to this study, the bone quality could be altered by the application of PRP.     

Synthetic bone grafts in peri-implant bone dehiscences: histological results in humans

This study describes the histological results found in three patients treated with osseointegrated implants and Bioplant HTR (Hard Tissue Replacement) synthetic bone graft in peri-implant dehiscences adjacent to implants. This therapy was carried out without the use of barrier membranes. Bioplant HTR is reported to act as its own barrier and prevent gingival soft tissue migration ingrowth. The histologic picture demonstrated that Bioplant HTR is osteoconductive and biocompatible, and can be used both as bone substitute and as a barrier for guided bone regeneration in implant therapy.     

引导洞形骨缺损再生模型中的哈弗氏管

目的 观察可吸收性海藻酸钙膜引导骨再生过程中哈弗氏管的再建及意义。方法 在家兔双侧下颌角前切迹处形成骨缺损。实验侧骨缺损上覆盖海藻酸钙膜，对照侧覆盖胶元膜。分别在术后1、2、4、6、8周时取出下颌骨，进行大体观察，X线观察，组织学观察，TGF-β与VEGF免疫组化染色。结果 海藻酸钙膜4周-6周吸收，胶元膜6周-8周吸收；前者异物巨噬细胞反应程度轻，后者反应程度重；术后6周内实验组哈弗氏管比对照侧出现早而多；前者大体观骨缺损愈合表面平整，后者表面突起；术后4周内实验侧TGF-β与VEGF阳性明显强于对照侧。结论 海藻酸钙膜比较元膜效果更好，哈弗氏系统再建和成骨作用均更快，且不影响骨再生修复。     

自体骨移植术中引导骨再生技术的应用研究

目的:比较单纯块状自体骨移植与自体骨 GBR技术水平骨增量效果.方法:20 例上颌前牙区牙槽嵴骨量不足的患者进行了牙槽嵴骨增量手术,其中8 例患者仅采用下颌骨颏部供骨Onlay植骨(A组),12患者采用自体骨移植 GBR技术(B组).骨增量后牙槽嵴的厚度分别在术后即刻以及术后4~6 月进行了测量.结果:2 组患者皆在术后4~6月出现了移植骨的吸收,A组患者出现的骨吸收较B组患者更为明显(P<0.01).结论:自体骨移植 GBR技术骨增量效果明显优于单纯的自体骨移植.     

红骨髓在骨移植中的应用

红骨髓是具有成骨性能的物质．它在骨移植中的应用已有较多的报道，近来，随着新的使用方法和新型材料的出现，红骨髓的应用又受到重视，可注射使用治疗不连接性骨折，与异体骨、异种骨或羟基磷灰石人工骨(HA)复合使用修复各种骨质缺损．临床报道效果十分理想．本文就红骨髓在骨移植方面的应用情况及近期进展作一综述。     

Selective COX-2 inhibitor reduces bone healing in bone defects

Anti-inflammatory agents have been reported to regulate bone healing. The aim of this study was to investigate the effect of a selective cyclooxygenase-2 inhibitor (meloxicam) on bone healing in calvarial defects in rats. Thirty-six adult male Wistar rats were included. After anesthesia, a linear incision was made through the skin of the scalp, a full-thickness flap was reflected and a 4 mm round defect was made with a trephine drill. The animals were randomly assigned to one of the following 4 treatment groups (9 animals each), including daily subcutaneous injections: A: saline solution for 15 days; B: saline solution for 45 days; C: 3 mg/kg of meloxicam for 15 days and D: 3 mg/kg of meloxicam for 45 days. The animals were sacrificed and the specimens, routinely processed. The bone filling was histometrically measured and statistical analysis, performed. Intergroup comparisons demonstrated that the meloxicam groups presented a significant reduction in bone healing when compared to their respective controls (group A, 44.5 +/- 5.75%, against group C, 57.5 +/- 7.25%, p < 0.05; group B, 40.25 +/- 13.75%, against group D, 52.25 +/- 17.25%). Within the limits of the present study, it can be concluded that selective cyclooxygenase-2 inhibitors may reduce bone healing in calvarial defects in rats after continuous administration.     

Three-dimensional technology and bone morphogenetic protein in frontal bone reconstruction

Osteoinductive bone morphogenetic proteins (BMPs) may be used in humans to facilitate healing of bony defects. The effect of different BMPs is, as with many other growth factors, highly dependent on the delivery vehicle. Bovine type I collagen is currently used in the clinical setting as a carrier and has been approved in several countries for human use. Here, we report the reconstruction of a frontal bone defect using heparin together with bovine type I collagen, hyaluronic acid, and fibrin as vehicles for BMP-2. A bony structure was created on the back of the patient by treating the latissimus dorsi muscle with the growth factor. A polyamide mold was used as a template to achieve the desired shape. The bone structure was transplanted into the defect site via microsurgical techniques. Although the prefabricated bone was not large enough tocover the entire frontal defect, the reconstruction was completed by using an additional cranial implant.     

Leukemia inhibitory factor enhances bone formation in calvarial bone defect

For bone defect reconstruction, locally administered cytokine plasmid was examined. Leukemia inhibitory factor (LIF) can bind to the osteoblast cell surface and induce bone formation both in vitro and in vivo. The authors investigated the local mouse LIF complementary deoxyribonucleic acid (cDNA) plasmid in the pcDNA 3 expression vector, which is promoted by cytomegalovirus and is stabilized by bovine growth hormone polyadenylation, with a gelatin sponge carrier. A total of 150 male Wistar rats were used. They were divided into three groups. Group 1 (N = 30) was treated with the gelatin carrier of the pcDNA 3 vector, group 2 (N = 90) was treated with three different doses of LIF cDNA (0.1, 1, and 10 micrograms) in the pcDNA 3-vector plasmid along with the gelatin carrier, and group 3 (N = 30) was treated with recombinant human bone morphogenetic protein -2. Ten animals in each group were euthanized at 1, 3, and 5 weeks postoperatively. Animals treated with LIF cDNA showed significantly enhanced bone mineral density (p < 0.05), as confirmed by dual-energy X-ray absorptiometry (DEXA), in 3 weeks compared with the control vehicle. By 3 weeks, the number of fibroblast-like cells and collagen fibers decreased, whereas the osteoblast-like cells increased inversely, as revealed during histological examination. LIF messenger ribonucleic acid demonstrated by in situ hybridization was observed most markedly in osteocytes of the LIF cDNA-treated group. Also, LIF peptide was detected in the same cell type by immunohistochemistry. Locally administered LIF cDNA plasmid in a gelatin carrier can increase bone density significantly, with subsequent bone formation, probably via osteocyte activation.     

Complications in bone grafting

Autogenous bone grafts continue to have wide use for reconstructing alveolar defects because of the many advantages associated with them. Although complications are low, the harvesting of bone grafts does have the risk of morbidity, which varies based on the harvest site chosen. Patients should be informed of possible complications associated with bone harvest as well as complications that many develop at the grafted site.     

A comparative study of anorganic xenogenic bone and autogenous bone implants for bone regeneration in rabbits

The aim of this study was to investigate the possible use and ultimate fate of anorganic xenogenic bone for the restoration of defects in the maxillae and mandibles of adult rabbits. Furthermore, anorganic xenogenic bone was compared with implanted autogenous bone particles with regard to the response of the surrounding connective tissue and possible resorption of these implants by multinucleated cells. Results showed that after 12 weeks, the implanted autogenous bone was actively resorbed by multinucleated cells, and new bone was formed in close apposition to the particles. In contrast, implanted anorganic xenogenic bone was degraded to a much lesser extent, and new bone was seen adjacent to the anorganic bone particles without signs of resorption. Further long-term studies are needed to determine whether anorganic xenogenic bone may be regarded as a resorbable material and whether any side effects occur as a result of this material's tendency to linger on in the recipient bed.     

Bio-Oss骨粉联合富血小板纤维蛋白在牙槽骨缺损种植引导骨再生后的骨量变化

目的：探讨Bio-Oss骨粉联合富血小板纤维蛋白在牙槽骨缺损种植引导骨再生后骨量的变化。方法：选择106例单颗前牙缺失伴唇侧骨缺损患者,进行种植体种植同期引导骨再生。按随机数字表法随机分为2组,实验组（53例）采用Bio-Oss骨粉联合富血小板纤维蛋白+生物膜引导骨再生,对照组（53例）采用Bio-Oss骨粉联合生物膜引导骨再生。评价2组种植成功率、术后并发症率、种植体唇侧骨壁厚度、骨缺损再生情况。采用SPSS 25.0软件包对数据进行统计学分析。结果：2组种植体种植成功率差异无统计学意义（96.23%:88.68%,P>0.05）。种植后12个月,实验组种植体唇侧骨壁厚度显著大于对照组[（2.72±0.43） mm:（2.51±0.36） mm,P<0.05],不同位点种植体唇侧骨壁厚度大于对照组（P<0.05）,出血指数[（0.32±0.02）:（0.42±0.03）]、探诊深度[（3.31±0.69） mm:（4.32±0.95） mm]、附着丧失[（3.06±0.52） mm:（5.24±1.35） mm]均显著小于对照组（P<0.05）,植骨高度[（2.61±0.52） mm:（2.31±0.35） mm]、成骨高度[（2.59±0.32） mm:（2.01±0.16） mm] 显著大于对照组（P<0.05）。2组患者并发症发生率相比差异无统计学意义（1.89%:5.66%, P>0.05）。结论：Bio-Oss骨粉联合富血小板纤维蛋白可减少骨缺损种植引导骨再生后骨量丢失,促进骨缺损再生。