纳米化表面钛合金内植物的界面组织学和生物力学评价

背景：假体松动是造成人工关节置换失败和翻修的主要原因之一。材料表面处理能够促进假体和骨组织界面的骨整合,提高假体的稳定性。目的：研究纳米化表面钛合金(Ti6A14V)內植物在动物体内的骨整合情况。方法：基于严重塑性变形原理制备纳米化表面钛合金。在比格犬股骨髁间植入普通表面、羟基磷灰石表面和纳米化表面钛合金内植物,置入后3个月取材,处死前行影像学观察,处死后取带有内植物的股骨髁制作不脱钙骨组织磨片,行Van Gieson苦味酸一品红染色,观察内植物和骨组织界面组织学情况,并进行骨动力学参数计算。同时行推出实验,比较不同表面内植物和骨组织界面生物力学情况。结果与结论：影像学检查,见内植物和骨组织结合良好;界面组织学可见羟基磷灰石表面和纳米化表面钛合金与骨界面有大量成熟骨小梁直接结合,两者界面骨结合率相似(P > 0.05),但都优于普通表面钛合金(P < 0.01);推出实验显示羟基磷灰石表面和纳米化表面钛合金內植物和骨组织的结合力相似(P > 0.05),但都优于普通表面钛合金(P < 0.001)。提示严重塑性变形原理制备的纳米化表面钛合金和羟基磷灰石表面钛合金一样具有成骨诱导活性,能够促进骨整合,具有良好的临床应用前景。

Histological and biomechanical evaluation in the interface between nano-surface titanium alloy implants and bone

BACKGROUND: Prosthetic looseness is the main cause of arthroplasty failure and revision. Surface treatment of the materials can promote the osseointegration rate and the stability of implants.OBJECTIVE:To evaluate the osseointergration of nano-surface titanium alloy (Ti6A14V) implant in animals. METHODS:Novel nanophase Ti6A14V substrates were prepared according to the severe plastic deformation principle. Ti6A14V substrate implants with common surface, hydroxyapatite-coated surface and nanophase surface were transplanted into each femoral intercondylar notch of beagle dogs. Three months later, all the beagle dogs were checked with X-ray film, then sacrificed. The condyles of femur with the implants were taken out, non-decalcification group sections were prepared for Van Gieson staining, bone ingrowth between the interfaces of the bone-implant were studied and kinesics parameter was measured. Pull-out test was applied to compare the shear strength between the interfaces of the bone-implant.RESULTS AND CONCLUSION:Radiographic examinations showed bone recovery around the implant and no obvious lucent gap in the interface of implant-bone. Histological examination suggested that lots of mature trabecular bone formed around Ti6A14V substrate implants with hydroxyapatite-coated surface and nanophase surface, the interface osseointegration rates showed no difference between them (P > 0.05), but all significantly higher than that of Ti6A14V substrate implants with common surface (P < 0.001). Pull-out test demonstrated that shear strength showed no difference between Ti6A14V substrate implants with hydroxyapatite-coated surface and nanophase surface (P > 0.05), but all significantly stronger than that of Ti6A14V substrate implants with common surface (P < 0.001). Ti6A14V substrate implants with nanophase surface improves the bone-implant osseointegration in vivo as hydroxyapatite-coated surface did, suggesting that novel nanophase Ti6A14V substrates prepared according to the severe plastic deformation principle may has a bone induction activity and might has a prosperous future for implant applications.