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Effects of Electrical Polarization of Hydroxyapatite ceramics on Bone Conduction

羟基磷灰石陶瓷的电极化对骨传导的影响

基本信息

批准号：
17500302
负责人：
ITOH Soichiro
金额：
$ 2.24万
依托单位：
Tokyo Medical and Dental University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

Experiment 1.Large surface charges can be induced on hydroxyapatite (HAp) ceramics by proton transport polarization, but this does not affect β-tricalcium phosphate (β-TCP) because of its low polarizability. We wished to examine differences in osteogenic cell activity and new bone growth between positively or negatively surface charged HAp and HAp/TCP plates using a calvarial bone defect model. In the first group of rats, test pieces were placed with their positively charged surfaces face down on the dura mater. In a second group, test pieces were placed with their negatively charged surfaces face down on the dura mater. A third group received non-charged test pieces. Histological examination, including enzymatic staining for osteoblasts and osteoclasts, was carried out. While no bone formation was observed at the pericranium, direct bone formation on the cranial bone debris and new bone growth expanded from the margins of the sites of injury to bridge across both the positively and ne … More gatively charged surfaces of HAp and HAp/TCP plates occurred. Electrical polarization of implanted plates, including positive charge, led to enhanced osteoblast activity, though decreased osteoclast activity was seen on the positively charged plate surface. Thus, polarization of HAp ceramics may modulate new bone formation and resorption.Experiment 2.Hydroxyapatite ceramics are used as implants to repair damaged/removed bone, and negative or positive electrical polarization enhances osteoblast and decreases osteoclast activity, respectively, in vivo. We compared the ability of electrically polarized and non-polarized hydroxyapatite with interconnected pores (IPHA) implants to promote bone growth. Polarized or non-treated IPHAs were implanted into the right or left femoral condyle of rabbits (N=10 in each group), and we performed histological examination, including enzymatic staining for osteoblasts and osteoclasts, three and six weeks after implantation. We observed improved bone ingrowth and increased osteoblast activity in polarized implants with complete bone penetration into polarized implants occurring as early as three weeks after surgery. In contrast, non-polarized implants were not fully ossified at six weeks after surgery. Furthermore, positively charged implant regions had decreased osteoclast activity compared to negatively charged or uncharged regions. We propose two different models to explain these observations. Less

实验1.质子输运极化可以在羟基磷灰石（HAp）陶瓷上产生较大的表面电荷，但由于β-磷酸三钙（β-TCP）的极化率较低，这对β-TCP陶瓷没有影响。我们希望使用颅骨骨缺损模型来检查表面带正电荷或负电荷的HAp和HAp/TCP板之间的成骨细胞活性和新骨生长的差异。在第一组大鼠中，将测试件以其带正电荷的表面面朝下放置在硬脑膜上。在第二组中，将测试件以其带负电荷的表面面朝下放置在硬脑膜上。第三组接受不带电的测试件。进行组织学检查，包括成骨细胞和破骨细胞的酶染色。虽然在颅骨周围没有观察到骨形成，但在颅骨碎片上有直接骨形成，新骨生长从损伤部位的边缘扩展到桥接阳性和阴性骨。 ...更多信息 HAp和HAp/TCP板的表面产生了负电荷。植入板的电极化，包括正电荷，导致成骨细胞活性增强，尽管在带正电荷的板表面上观察到破骨细胞活性降低。实验2.将羟基磷灰石陶瓷作为植入体用于修复损伤/去除的骨，负或正电极化分别增强成骨细胞和降低破骨细胞的活性。我们比较了电极化和非电极化多孔羟基磷灰石（IPHA）植入物促进骨生长的能力。将极化或未处理的IPHA植入兔的右侧或左侧股骨髁（每组N=10），并在植入后3周和6周进行组织学检查，包括成骨细胞和破骨细胞的酶染色。我们观察到极化种植体中骨长入改善，成骨细胞活性增加，早在术后三周就发生了完全骨渗透到极化种植体中。相比之下，非极化种植体在术后6周没有完全骨化。此外，与带负电荷或不带电荷的区域相比，带正电荷的植入区域具有降低的破骨细胞活性。我们提出了两种不同的模型来解释这些观察结果。少