Merema Bram B J, Spijkervet Frederik K L, Kraeima Joep, Witjes Max J H
Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands.
Sci Rep. 2025 Jan 3;15(1):644. doi: 10.1038/s41598-024-82964-w.
In cases of large mandibular continuity defects resulting from malignancy resection, the current standard of care involves using patient-specific/custom titanium reconstruction plates along with autogenous grafts (fibula, scapula, or iliac crest segments). However, when grafts are not feasible or desired, only the reconstruction plate is used to bridge the gap. Unfortunately, metal osteosynthesis and reconstruction plates, including titanium, exhibit adverse effects such as stress-shielding and limitations in accurate postoperative irradiation (especially with proton-beam therapy). To address these issues, in this study we explore, develop and validate a non-metallic solution: a topology-optimized polyetheretherketone (PEEK) load-bearing implant for large non-grafted mandibular continuity defects. In order to thoroughly validate the developed PEEK reconstruction, a dedicated MANDYBILATOR testing apparatus was developed. Using the MANDYBILATOR finite element analysis results of the implant were confirmed and the PEEK implant was mechanically validated for both static and dynamic loading. Results show that the PEEK reconstructed mandible is comparably strong as the unreconstructed mandible and is unlikely to fail due to fatigue. Our PEEK implant design has the mechanical potential to act as a substitute for the current titanium plates used in the reconstruction of continuity defects of the mandible. This may potentially lead to optimised patient-specific reconstructions, with the implants matching the bone's stiffness and possessing radiolucent properties which are useful for radiographic follow-ups and radiotherapy. Furthermore, the addition of the dynamic/cyclic MANDYBILATOR apparatus allows for more realistic application of the in-vivo loading of the mandible and can provide added insights in biomechanical behaviour of the mandible.
在因恶性肿瘤切除导致下颌骨连续性大缺损的病例中，当前的标准治疗方法是使用患者特异性/定制钛重建板以及自体移植物（腓骨、肩胛骨或髂嵴段）。然而，当移植物不可行或不被期望时，仅使用重建板来桥接间隙。不幸的是，金属骨固定术和重建板，包括钛板，会表现出诸如应力屏蔽等不良反应以及术后精确放疗（尤其是质子束治疗）方面的局限性。为了解决这些问题，在本研究中我们探索、开发并验证了一种非金属解决方案：一种用于大型非移植下颌骨连续性缺损的拓扑优化聚醚醚酮（PEEK）承重植入物。为了全面验证所开发的PEEK重建物，开发了一种专门的MANDYBILATOR测试装置。利用该装置确认了植入物的有限元分析结果，并对PEEK植入物进行了静态和动态加载的力学验证。结果表明，PEEK重建的下颌骨与未重建的下颌骨强度相当，不太可能因疲劳而失效。我们的PEEK植入物设计在力学上有潜力替代目前用于下颌骨连续性缺损重建的钛板。这可能潜在地导致优化的患者特异性重建，植入物与骨骼的刚度相匹配，并具有射线可透过性，这对影像学随访和放射治疗很有用。此外，动态/循环MANDYBILATOR装置的增加允许更真实地模拟下颌骨的体内加载，并能提供关于下颌骨生物力学行为的更多见解。
