Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Paar, L.
Evaluation of a magnesium-based implant in the growing rat model
Humanmedizin; [ Diplomarbeit ] Medical University Graz; 2021. pp. 62
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- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Sommer Nicole
- Weinberg Annelie-Martina
- Altmetrics:
- Abstract:
- Background: Osteosynthesis has significantly gained in relevance in pediatric orthopedics and traumatology over the last decades. Permanent metal implants like titanium, stainless steel and other metallic alloys are used for fracture treatment. Currently, implant removal is performed frequently in order to avoid possible long term side effects such as growth disturbance, discomfort or accumulation of corrosion products. Accordingly, another anesthesia and hospitalization is needed. New implant materials composed of magnesium (Mg) and Mg alloys exhibit promising features including excellent biocompatibility and mechanical properties meeting the demands for an enhanced fracture stabilizing implant in pediatric orthopedics and traumatology. Moreover, Mg-based implants dissolve after a certain period of time to their full extent, rendering a second surgery for implant removal unnecessary. In this study we investigated the in vivo degradation behavior of an Mg-based alloy synthesized with zinc and calcium (ZX00) in rats over a time period of 24 weeks. Methods: Seven, female 6-weeks old Sprague Dawley rats underwent bilateral and transcortical implantation of cylindrical ZX00 pins into the proximal metaphysis of the tibia. Three Sprague Dawley rats underwent the same surgical intervention without implant, thereby serving as sham controls. To observe implant degradation and osseointegration, in vivo low-medium resolution micro-computed tomography was performed immediately after as well as 2, 6, 12, 15, 18 and 24 weeks after implantation. Images were three-dimensionally reconstructed and implant volume, implant surface and hydrogen gas formation was calculated using MIMICS Software, version 22. Results: Our results showed a good osseointegration and homogenous degradation behavior of ZX00 with appropriate hydrogen gas formation. Although implants were inserted in close proximity to the growth plate, no negative effect on longitudinal bone growth could be observed. Conclusion: We showed homogenous degradation, adequate gas evolution and good osseointegration of Mg-based ZX00 implants without bone growth determination. We conclude that ZX00 constitutes an appropriate biodegradable material for utilization in pediatric orthopedics and traumatology, however, further studies are needed to prove rigidity of the material especially in the first six to twelve weeks of fracture healing.