Ficklin Michael G, Kunkel Kevin A R, Suber Jonathan T, Gerard Patrick D, Kowaleski Michael P
Dr. Kevin A. R. Kunkel, VCA Animal Specialty Center of South Carolina, 3912 Fernandina Road, Columbia, SC 29210, United States, Phone: +1 803 798 0803, Fax: +1 803 798 7916, E-mail:
Vet Comp Orthop Traumatol. 2016 Sep 20;29(5):394-401. doi: 10.3415/VCOT-16-01-0005. Epub 2016 Jul 29.
Numerous studies have examined the biomechanics of polymethyl methacrylate (PMMA) with added antibiotics, but direct comparison between studies is difficult. Our purpose was to evaluate the effects of the addition of antibiotic drugs and silver on compressive and bending strength of PMMA. Our null hypothesis was that there would be no significant difference in the compressive strength or bending strength of PMMA with the addition of silver or varying amounts of antibiotic drugs.
Polymethyl methacrylate was mixed with cefazolin, gentamicin, vancomycin, or silver; the control was PMMA alone. Antibiotic groups contained 20 g PMMA and 0.5 g, 1 g, 2 g, or 3 g of antibiotic. Silver groups had 0.25 g silver powder alone added to 20 g PMMA or silver with PMMA and 0, 0.5 g or 1 g of antibiotic. Samples underwent four-point bending and compression testing in air at room temperature and prevailing humidity. Pairwise comparisons between groups and to the ASTM and ISO standards were performed.
Compression: All antibiotic and silver groups were weaker than the control. Samples with cefazolin tended to be stronger than other antibiotic groups with equivalent doses of antibiotic. All groups were above the ASTM standard, except 3 g vancomycin. Four-point bending: The addition of antibiotics did not significantly affect bending strength in groups with lower doses of antibiotics. The silver + PMMA group was weaker than the control. No groups were significantly below the ISO standard except the 3 g vancomycin group.
The addition of antibiotic or silver decreased the biomechanical strength in all samples, but not below the ASTM or ISO standard for most groups. The addition of cefazolin appears to affect strength the least, while high doses of vancomycin alter strength the most.
众多研究已对添加抗生素的聚甲基丙烯酸甲酯（PMMA）的生物力学进行了研究，但各研究之间的直接比较存在困难。我们的目的是评估添加抗生素药物和银对PMMA抗压强度和抗弯强度的影响。我们的零假设是，添加银或不同剂量抗生素药物的PMMA在抗压强度或抗弯强度上不会有显著差异。
将聚甲基丙烯酸甲酯与头孢唑林、庆大霉素、万古霉素或银混合；对照组仅为PMMA。抗生素组包含20克PMMA和0.5克、1克、2克或3克抗生素。银组是在20克PMMA中单独添加0.25克银粉，或银与PMMA以及0、0.5克或1克抗生素混合。样品在室温及当前湿度的空气中进行四点弯曲和压缩测试。对各实验组之间以及与ASTM和ISO标准进行成对比较。
压缩测试：所有抗生素和银组均比对照组弱。含头孢唑林的样品在等量抗生素情况下往往比其他抗生素组更强。除3克万古霉素组外，所有组均高于ASTM标准。四点弯曲测试：在低剂量抗生素组中，添加抗生素对弯曲强度无显著影响。银+PMMA组比对照组弱。除3克万古霉素组外，没有组显著低于ISO标准。
添加抗生素或银会降低所有样品的生物力学强度，但大多数组未低于ASTM或ISO标准。添加头孢唑林似乎对强度影响最小，而高剂量万古霉素对强度影响最大。
