Processing and coating of open-pored absorbable magnesium-based bone implants

authored by: Stefan Julmi, Ann Kathrin Krüger, Anja Christina Waselau, Andrea Meyer-Lindenberg, Peter Wriggers, Christian Klose, Hans Jürgen Maier
Abstract: Large bone defects or fractures must be treated with an implant or transplant. Resorbable implants are attractive as these require only one surgery, whereas bone autografts, which can be cut off from the same person's hip, require more than one procedure. Moreover, porous structures promote the ingrowth of the patient's bone. Thus, the objective of the present study was to develop open-pored biodegradable implant structures with different pore sizes that provide for both adequate degradation behaviour and mechanical properties that match with those of bone. The magnesium alloys LAE442 and La2 were employed in this study, as these materials are known to feature good biocompatibility and mechanical properties close to bone. It was possible to cast magnesium sponges with different pore sizes using the alloy LAE442. However, with the Mg–La2 alloy, only sponges with a minimum pore size of 0.5 mm could be produced. Overall, the sponges cast with the LAE442 alloy showed higher strength, even though the strengths of the dense parts were similar in both alloys tested. In terms of castability and mechanical behaviour, the LAE442 alloy turned out to be more favourable. In order to adapt the implant degradation behaviour to the bone ingrowth behaviour, coating of the magnesium sponges with calcium phosphate and polylactic acid was also investigated. Additionally, the different coatings were tested on their adhesive forces and influences to the in-vitro degradation behaviour.
Organisation(s): Institute of Materials Science
Institute of Continuum Mechanics
External Organisation(s): Ludwig-Maximilians-Universität München (LMU)
Type: Article
Journal: Materials Science and Engineering C
Volume: 98
Pages: 1073-1086
No. of pages: 14
ISSN: 0928-4931
Publication date: 05.2019
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Condensed Matter Physics, Mechanics of Materials, Mechanical Engineering, General Materials Science
Electronic version(s): https://doi.org/10.1016/j.msec.2018.12.125 (Access: Closed)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{6cf17133d5504265a68cac2d616171fa,
title = "Processing and coating of open-pored absorbable magnesium-based bone implants",
abstract = "Large bone defects or fractures must be treated with an implant or transplant. Resorbable implants are attractive as these require only one surgery, whereas bone autografts, which can be cut off from the same person's hip, require more than one procedure. Moreover, porous structures promote the ingrowth of the patient's bone. Thus, the objective of the present study was to develop open-pored biodegradable implant structures with different pore sizes that provide for both adequate degradation behaviour and mechanical properties that match with those of bone. The magnesium alloys LAE442 and La2 were employed in this study, as these materials are known to feature good biocompatibility and mechanical properties close to bone. It was possible to cast magnesium sponges with different pore sizes using the alloy LAE442. However, with the Mg–La2 alloy, only sponges with a minimum pore size of 0.5 mm could be produced. Overall, the sponges cast with the LAE442 alloy showed higher strength, even though the strengths of the dense parts were similar in both alloys tested. In terms of castability and mechanical behaviour, the LAE442 alloy turned out to be more favourable. In order to adapt the implant degradation behaviour to the bone ingrowth behaviour, coating of the magnesium sponges with calcium phosphate and polylactic acid was also investigated. Additionally, the different coatings were tested on their adhesive forces and influences to the in-vitro degradation behaviour.",
keywords = "Biocompatible magnesium alloys, Coating, Investment casting, Magnesium sponges, Resorbable implants, Magnesium/chemistry, Biocompatible Materials/chemistry, Bone and Bones/metabolism, Humans, Calcium Phosphates/chemistry, Absorbable Implants, Alloys/chemistry, Bone Transplantation/methods, Materials Testing/methods, Porosity",
author = "Stefan Julmi and Kr{\"u}ger, {Ann Kathrin} and Waselau, {Anja Christina} and Andrea Meyer-Lindenberg and Peter Wriggers and Christian Klose and Maier, {Hans J{\"u}rgen}",
note = "Funding Information: This research was supported by the German Research Foundation (DFG) within the project “Interfacial effects and ingrowing behaviour of magnesium-based foams as bioresorbable bone substitute material” (grant No. MA 1175/52-1, ME 1941/3-1 and WR 19/56-1; 271761343). The Xradia 520 Versa (grant No. MA1175/67-1; 316923185) that has been used in this study, was sponsored by the DFG.",
year = "2019",
month = may,
doi = "10.1016/j.msec.2018.12.125",
language = "English",
volume = "98",
pages = "1073--1086",
journal = "Materials Science and Engineering C",
issn = "0928-4931",
publisher = "Elsevier BV",
}