Department of Urology, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Kobe, Japan.
Department of Mechanical Engineering, Kobe University, Kobe, Japan.
World J Urol. 2021 Jan;39(1):201-208. doi: 10.1007/s00345-020-03138-7. Epub 2020 Feb 28.
Metallic medical devices are typically constructed from non-bioabsorbable metals that remains in the body and causes considerable complications. Particularly in the urinary tract, calculus, intractable infection, and misdiagnosis as calculus are often caused by non-bioabsorbable metals. Here, we developed a zinc-magnesium alloy as a new bioabsorbable metal and sought to evaluate the bioabsorbable behavior of zinc and zinc-magnesium alloy in a rat bladder implantation model.
We prepared zinc-magnesium alloy wires with various proportions of magnesium and investigated the strength, shape retention, formability, and absorbability of these novel materials. Then, we implanted zinc and zinc-magnesium alloy rings formed by the wires into rat bladder. Rats were euthanized at the end of the observation period, and the rings were removed for volume evaluation. Extracted bladder tissues were subjected to histological analysis.
The strength of the zinc wire was enhanced by more than fourfold upon the addition of magnesium, without loss of ductility. Linear reduction of ring volume in urine was observed based on the concentration of magnesium within the ring. Nearly all rings were covered with a thin layer of calculus. Histological findings of the transected urinary bladder tissues did not differ among groups.
Zinc-magnesium alloy is a promising candidate for use as a bioabsorbable medical device in the urinary tract.
金属医疗器械通常由不可生物降解的金属制成，这些金属留在体内会引起严重的并发症。特别是在泌尿道中，结石、难治性感染和误诊为结石的情况经常由不可生物降解的金属引起。在这里，我们开发了一种锌镁合金作为一种新型可生物降解金属，并试图在大鼠膀胱植入模型中评估锌和锌镁合金的可生物降解行为。
我们制备了具有不同镁比例的锌镁合金线，并研究了这些新型材料的强度、形状保持、可成形性和可吸收性。然后，我们将由这些线材制成的锌和锌镁合金环植入大鼠膀胱。在观察期结束时处死大鼠，并取出环进行体积评估。提取的膀胱组织进行组织学分析。
在添加镁的情况下，锌线的强度提高了四倍以上，而延展性没有损失。根据环内镁的浓度，观察到环体积在尿液中的线性减少。几乎所有的环都被一层薄薄的结石覆盖。各组的膀胱组织横切面的组织学发现没有差异。
锌镁合金是一种很有前途的可生物降解医用材料，可用于泌尿道。
