Charité - Universitätsmedizin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Department of Oral and Maxillofacial Surgery, Augustenburger Platz 1, 13353 Berlin, Germany.
Charité - Universitätsmedizin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Department of Oral and Maxillofacial Surgery, Augustenburger Platz 1, 13353 Berlin, Germany.
Acta Biomater. 2024 Sep 1;185:98-110. doi: 10.1016/j.actbio.2024.07.005. Epub 2024 Jul 11.
Magnesium as a biodegradable material offers promising results in recent studies of different maxillo-facial fracture models. To overcome adverse effects caused by the fast corrosion of pure magnesium in fluid surroundings, various alloys, and surface modifications are tested in animal models. In specified cases, magnesium screws already appeared for clinical use in maxillofacial surgery. The present study aims to compare the bone healing outcome in a non-load-bearing fracture scenario of the forehead in sheep when fixed with standard-sized WE43 magnesium fixation plates and screws with plasma electrolytic oxidation (PEO) surface modification in contrast to titanium osteosynthesis. Surgery was performed on 24 merino mix sheep. The plates and screws were explanted en-bloc with the surrounding tissue after four and twelve weeks. The outcome of bone healing was investigated with micro-computed tomography, histological, immunohistological, and fluorescence analysis. There was no significant difference between groups concerning the bone volume, bone volume/ total volume, and newly formed bone in volumetric and histological analysis at both times of investigation. The fluorescence analysis revealed a significantly lower signal in the magnesium group after one week, although there was no difference in the number of osteoclasts per mm. The magnesium group had significantly fewer vessels per mm in the healing tissue. In conclusion, the non-inferiority of WE43-based magnesium implants with PEO surface modification was verified concerning fracture healing under non-load-bearing conditions in a defect model. STATEMENT OF SIGNIFICANCE: Titanium implants, the current gold standard of fracture fixation, can lead to adverse effects linked to the implant material and often require surgical removal. Therefore, degradable metals like the magnesium alloy WE43 with plasma electrolytic oxidation (PEO) surface modification gained interest. Yet, miniplates of this alloy with PEO surface modification have not been examined in a fracture defect model of the facial skeleton in a large animal model. This study shows, for the first time, the non-inferiority of magnesium miniplates compared to titanium miniplates. In radiological and histological analysis, bone healing was undisturbed. Magnesium miniplates can reduce the number of interventions for implant removal, thus reducing the risk for the patient and minimizing the costs.
镁作为一种可生物降解的材料，在不同的颌面骨折模型的研究中取得了有前景的结果。为了克服纯镁在流体环境中快速腐蚀带来的不良影响，各种合金和表面改性都在动物模型中进行了测试。在特定情况下，镁螺钉已经出现在颌面外科的临床应用中。本研究旨在比较在绵羊额骨非承重骨折模型中，使用标准尺寸 WE43 镁固定板和螺钉与等离子电解氧化（PEO）表面改性与钛骨合成物固定时的骨愈合结果。在 24 只美利奴混合羊身上进行了手术。在四周和十二周后，将带有周围组织的板和螺钉整块取出。使用微计算机断层扫描、组织学、免疫组织化学和荧光分析来研究骨愈合的结果。在两次研究中，各组的骨体积、骨体积/总体积和新形成的骨在体积和组织学分析方面均无显著差异。荧光分析显示，尽管破骨细胞数量没有差异，但镁组在一周后信号明显较低。镁组愈合组织中的血管数量明显较少。总之，在缺陷模型中，非承重条件下 WE43 基镁植入物与 PEO 表面改性的非劣效性得到了验证。
作为骨折固定的当前金标准的钛植入物会导致与植入物材料相关的不良影响，并且通常需要手术取出。因此，像 WE43 镁合金这样的可降解金属，具有等离子电解氧化（PEO）表面改性，引起了人们的兴趣。然而，这种合金的带有 PEO 表面改性的微型板尚未在大型动物模型的面部骨骼骨折缺陷模型中进行检查。这项研究首次表明，与钛微型板相比，镁微型板具有非劣效性。在放射学和组织学分析中，骨愈合未受干扰。镁微型板可以减少植入物取出的次数，从而降低患者的风险并最小化成本。
