Intervertebral disc spacers using bioactive ceramics have been used to treat degenerative spinal disease. Tooth-shaped spacers are commonly used to prevent migration, but there is a possibility of fracture when inserted or after insertion. Intervertebral disc spacers with either an isosceles triangle-shaped tooth (T1) or a right triangle-shaped tooth (T2) were used as a control group. The design factors for the experimental group were modified to prevent fractures induced by stress concentration, and the surfaces of the spacers were designed as either an isosceles triangle-shaped valley (V1) or a right triangle-shaped valley (V2). Linear analysis using finite element model (FEM) was performed, and Von Mises stress distribution was calculated by applying 1000 N of uniformly distributed load. Samples of the V2 design were made with bioactive glass-ceramics (BGS-7) and evaluated for compressive strength, fatigue degree, and impact strength. Von Mises stress was highest at the first tooth from the posterior side for the control group and at the center for the experimental group. Compared with the control group, the experimental group showed 18.4% and 82.5% reduction (V1 vs. T1 and V2 vs. T2, respectively) in the maximum stress at the bottom of the valleys. The FEM analysis revealed that the V2 design had the most even load distribution. The V2 samples with bioactive glass-ceramics were evaluated for compressive strength, and all six samples were not fractured up to 24 000 N. However, the average impact strength was 19.42 kN, suggesting that momentary force caused damage at a lower load than compression with a steady speed. The BGS-7 intervertebral disc spacer with V2 design was not fractured during the fatigue test at maximum pressure of 8000 N, R ≥10, 5 Hz, and 5 million cycles. These data confirm that the BGS-7 spacer with the V2 design may be clinically applicable. Collectively, the modified surface geometry of the experimental group significantly lowered Von Mises stress values at the bottom of the valleys, and thus the possibility of fracture by compressive load was greatly reduced. Also, impact during insertion was confirmed to cause fracture more easily, as the impact strength was lower than the compressive strength in the experimental group.

译文

使用生物活性陶瓷的椎间盘垫片已用于治疗退行性脊柱疾病。通常使用齿形垫片来防止迁移,但是插入时或插入后有断裂的可能性。将具有等腰三角形牙齿 (T1) 或直角三角形牙齿 (T2) 的椎间盘间隔物用作对照组。修改了实验组的设计因素,以防止应力集中引起的裂缝,并将垫片的表面设计为等腰三角形谷 (V1) 或直角三角形谷 (V2)。使用有限元模型 (FEM) 进行线性分析,并通过1000 N均匀分布的载荷计算Von Mises应力分布。用生物活性玻璃陶瓷 (BGS-7) 制成V2设计的样品,并评估其抗压强度,乏力程度和冲击强度。对照组从后侧开始的第一颗牙齿和实验组的中心位置的Von Mises应力最高。与对照组相比,实验组在谷底的最大应力显示出18.4% 和82.5% 的降低 (分别为V1对T1和V2对T2)。有限元分析表明,V2设计的载荷分布最均匀。评估了具有生物活性微晶玻璃的V2样品的抗压强度,并且所有六个样品的断裂都不超过24 000 N。但是,平均冲击强度为19.42 kN,这表明瞬时力在比稳定速度的压缩低的载荷下引起损坏。在最大压力为8000 N,R ≥ 10、5Hz和500万个循环的疲劳试验中,采用V2设计的BGS-7椎间盘垫片没有断裂。这些数据证实具有V2设计的BGS-7间隔物可以在临床上适用。总的来说,实验组的修改后的表面几何形状显着降低了谷底部的Von Mises应力值,因此大大降低了压缩载荷导致断裂的可能性。此外,由于插入过程中的冲击强度低于实验组的抗压强度,因此确认插入过程中的冲击更容易导致断裂。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录