The Experts below are selected from a list of 1113 Experts worldwide ranked by ideXlab platform
Andrea Meyerlindenberg - One of the best experts on this subject based on the ideXlab platform.
-
evaluation of the biocompatibility of two magnesium alloys as Degradable Implant materials in comparison to titanium as non resorbable material in the rabbit
2013Co-Authors: Carolin Hampp, Janin Reifenrath, Dirk Bormann, Nina Angrisani, Janmarten Seitz, Andrea MeyerlindenbergAbstract:Abstract The aim of this study is to compare the biocompatibility of the two magnesium based alloys LAE442 and LANd442 with that of titanium. For this purpose, cylindrical Implants were introduced into the medullary cavity of rabbit's tibiae for 4 and 8 weeks. Animals without any Implant served as a control. In the follow-up, clinical, X-ray and μCT-investigations were performed to evaluate the reactions of the bone towards the Implanted materials. After euthanasia, ex vivo μCT- and histological investigations were performed to verify the results of the in vivo tests. It could be shown that all materials induce changes in the bone. Whereas LANd442 caused the most pronounced reactions, such as increasing bone volume and bone porosity and decreasing bone density, titanium showed the most bone–Implant contact by forming trabeculae. The tibiae of rabbits without Implants also reacted by forming cavities, it is therefore assumed that the surgery method itself influences the bone.
-
histological and molecular evaluation of iron as Degradable medical Implant material in a murine animal model
2012Co-Authors: Pete P Muelle, Sylvia Arnold, Muhammad Ada, Dirk Orma, Friedrichwilhelm Ach, Andreas Drynda, Andrea Meyerlindenberg, Hansjorg Hause, Matthias PeusteAbstract:A small animal model was established to evaluate the potential of iron as a Degradable Implant material. After insertion into the tail of mice, the Implants gradually degraded over a clinically relevant time period of several months. Histological analysis and gene expression data from whole-genome microarray analyses indicated a limited inflammatory reaction. No evidence of cellular responses to excess iron ions was detected, suggesting that the iron degradation products were metabolically inactive. Iron-rich compounds could be detected in the vicinity of the Implant and in individual cells distant from the Implantation site. These results demonstrate that the mouse model could be useful for the primary in vivo evaluation of novel Implant materials and that iron degradation products can accumulate in diverse organs of the body.
-
biocompatible magnesium alloys as Degradable Implant materials machining induced surface and subsurface properties and Implant performance
2011Co-Authors: Berend Denkena, Arne Lucas, Fritz Thorey, Hazibullah Waizy, Nina Angrisani, Andrea MeyerlindenbergAbstract:Annually several million people suffer bone fractures caused by accidents or diseases. Many of those fractures are too complex for an external medical treatment but have to be surgically fixated by internal bone Implants. Traditional methods of osteosynthesis or osteotomy use permanent metal Implants e.g. bone screws and bone plates made of steel or titanium alloys, but permanent metal Implants have to be excised. Especially young patients in growth require the Implant removal. Usually, metal Implants should be removed latest one or two years after the first surgery. BioDegradable Implants, which dissolve in the human organism, therefore represent an appropriate solution. Here magnesium as a Degradable Implant material provides both biocompatibility and sufficient mechanical properties. Studies have shown that magnesium, which is an essential element of the human organism, is suitable as a Degradable biomaterial for use in medical Implants. Also in relation to biomechanical requirements the suitability of magnesium as an Implant material in has already been proven. Due to mechanical properties superior to the bone, magnesium Implants show biomechanical properties comparable to conventional steel Implants in standardized biomechanical tests. Also an influence of surface properties on the degradation behavior is already known. Interdisciplinary research between medical and engineering sciences focuses on the development of Degradable magnesium Implants for osteosynthesis. The removal of those Implants after convalescence of the fractured bone is no longer necessary, resulting in a considerable benefit for patients and the public health care system. The aim is to preset individual degradation kinetics for Implants made of biocompatible magnesium alloys through adjusting surface and subsurface properties of the magnesium Implants for specific indications. Adapted machining processes exhibit possibilities to adjust those properties. The idea of Implants specifically adapted to their desired function and functional period within a possible range of surface or subsurface modifications is illustrated schematically in Figure 1for different Implant designs (V1 and V2). The healing
-
magnesium alloys as promising Degradable Implant materials in orthopaedic research
2011Co-Authors: Janin Reifenrath, Dirk Bormann, Andrea MeyerlindenbergAbstract:Magnesium alloys as Degradable Implant materials in orthopaedic research received a lot of interest in recent years (Witte et al., 2007a; Xu et al., 2008; Zhang et al., 2010). The application of resorbable Implant material avoids an Implant removal surgery and therewith helps to diminish the costs and the burden for the patient. In comparison to other Degradable Implant materials like polymers, magnesium alloys excel in higher tensile and compressive strength and the young’s modulus is near to cortical bone (Hofmann, 1995; Staiger et al., 2006; Kaese, 2002). Another advantage that leads to the choice of magnesium alloys as Implant material is the fact, that magnesium is a natural component of the body and furthermore has many important functions within the body (Hartwig, 2001). Magnesium is tested as non-allergenic (Witte et al., 2007a) and due to several studies it is assumed, that it stimulates new bone formation in vitro and in vivo (Revell et al., 2004; Zreitqat et al., 2002; Witte et al., 2007b). For the application as orthopedic Implant material in weight bearing bones, only magnesium alloys with a slow corrosion rate are useful. A high corrosion rate results in gas formation, a too fast loss of mechanical stability and a considerably higher bone remodelling activity (Thomann et al., 2009; Krause et al., 2010). Beside to different coating facilities (Witte et al., 2009; Zhang et al., 2010) and surface treatments (von der Hoh et al., 2006; Hanzi et al., 2008), in particular the alloying of aluminium, lithium, rare earth metals or calcium decrease the corrosion rate in vitro and in vivo (Kaese, 2002; Staiger, 2006; Hanzi et al., 2008; Krause et al., 2010; Thomann et al., 2009). However, in vivo and in vitro corrosion rates can be quite different (Witte et al., 2006; Zhang et al., 2010), which makes it more difficult to develop and adapt magnesium alloys for biomedical use. In order to investigate if the chosen magnesium-alloys are suitable for the use in orthopedic applications, in vivo-studies in rabbit tibiae were conducted. Therefor the selected and in vitro examined magnesium alloys LAE442, WE43, MgCa0.8, AX30, ZEK100 were Implanted into the rabbit tibia and examined with regard to the mechanical stability, the in vivo corrosion rate and the biocompatibility. For the in vivo investigation of the Implant materials, the rabbit was used as established animal model for orthopaedic applications (Pearce, 2007). All animal experiments were conducted under an ethic committee approved protocol in accordance with German federal welfare legislation. Five rabbits were used for each group. Extruded pins with 2.5 mm in
-
degradation behaviour and mechanical properties of magnesium Implants in rabbit tibiae
2010Co-Authors: Annett Krause, Dirk Bormann, Christian Krause, Friedrichwillhelm Bach, Henning Windhagen, Andrea MeyerlindenbergAbstract:To investigate the initial mechanical strength and the degradation behaviour with the associated changes in mechanical properties of magnesium-based osteosynthesis Implants, 30 rabbits were Implanted with cylindrical pins of the alloys MgCa0.8 (magnesium with 0.8 wt% calcium), LAE442 (magnesium with 4 wt% lithium, 4 wt% aluminium and 2 wt% rare earths) and WE43 (magnesium with 4 wt% yttrium and 3 wt% rare earths). The Implants were inserted into the medullary cavity of both tibiae. After 3 and 6 months, each half of the animals was euthanized, respectively, and the Implants were taken out. A determination of volume, three-point bending tests, scanning electron microscopy (SEM) and energy dispersive X-ray analyses as well as metallographic and μ-computed tomography examinations were accomplished. All Implants were clinically well tolerated. MgCa-Implants showed the least initial strength and the highest loss in volume after 6 months. SEM- and μ-computed tomography examinations revealed a pronounced pitting corrosion. Therefore, their use as Degradable Implant material seems to be limited. LAE442 has the best initial strength which seems to be sufficient for an application in weight-bearing bones. The degradation behaviour is very constant. However, possible unknown side effects of the rare earths have to be excluded in further investigations on biocompatibility. Considering all results of WE43, its application as osteosynthesis material for fracture repair is ineligible due to its heterogeneous and unpredictable degradation behaviour.
Peter J Uggowitzer - One of the best experts on this subject based on the ideXlab platform.
-
on the immersion testing of Degradable Implant materials in simulated body fluid active ph regulation using co2
2013Co-Authors: Michael Schinhammer, Joelle Hofstetter, Christian Wegmann, Frank Moszner, Jorg F Loffler, Peter J UggowitzerAbstract:Predictions of in vivo degradation behavior derived from laboratory experiments are of great importance in the development of bioDegradable materials. A key issue is the simulation of the physiological conditions found in living organisms. Generally, the testing solution and in particular the pH buffer have a significant influence on the outcome of degradation experiments. This study presents results obtained from immersion tests in SBF buffered with gaseous CO2. The control of the pH value by means of CO2 has the advantage of better reflecting physiological conditions, and allows the carrying out of in vitro experiments which are closer to the in vivo situation.
-
high strength magnesium alloys for Degradable Implant applications
2011Co-Authors: Petra Gunde, Anja C Hanzi, Alla S Sologubenko, Peter J UggowitzerAbstract:This article describes the design principles deployed in developing high-strength and ductile Mg-Zn-Zr-Ca-Mn(-Yb) alloys based on a concept, which aims to restrict grain growth considerably during alloy casting and forming. The efficiency of the development approach is discussed. Moreover, the microstructure and phase analysis of the alloys subjected to different thermal treatments are presented and the influence of the alloy composition, particularly the addition of Yb, on the evolution of the microstructure is discussed in connection with the mechanical properties of the materials. The newly developed alloys exhibit high strength (yield stress of up to 350 MPa) at considerable ductility (elongation to fracture of up to 19%) in the as-extruded state and reveal age hardening potential (increase in hardness of 10-15% compared to that in the recrystallization heat-treated state). Appropriate heat treatments enable tailoring of the strength-ductility relation. Thermal annealing of the material resulted in a remarkable increase in ductility (elongation to fracture of more than 20% for all heat-treated samples) while high strength is retained (yield stress ranging from 210 to 315 MPa). We attribute the attractive mechanical properties of the developed alloys to their fine-grained microstructure, where the grain boundaries and lattice defects are stabilized by second phase particles formed during casting and thermal treatments.
-
on the in vitro and in vivo degradation performance and biological response of new bioDegradable mg y zn alloys
2010Co-Authors: Anja C Hanzi, Michael Schinhammer, Jorg F Loffler, Isabel Gerber, Peter J UggowitzerAbstract:A design strategy deployed in developing new bioDegradable Mg–Y–Zn alloys is summarized and the key factors influencing their suitability for medical applications are described. The Mg–Y–Zn alloys reveal microstructural features and mechanical characteristics expected to be appropriate for vascular intervention applications. The focus of this article lies in the evaluation of the degradation performance and biological response of the alloys with respect to their potential as Implant materials (stents). The degradation characteristics analyzed by immersion testing and electrochemical impedance spectroscopy in simulated physiological media reveal slow and homogeneous degradation. In vitro cell tests using human umbilical vein endothelial cells indicate good cytocompatibility on the basis of the alloys’ eluates (extracts). Animal studies carried out with pigs on Mg–2Y–1Zn (in wt.%) reveal an auspicious in vivo performance. Evaluation of preparations derived from Implants in various types of tissues indicates homogeneous degradation and only limited gas formation during in vivo testing. The characteristics of the tissue reactions indicate good biocompatibility. The new Mg–Y–Zn alloys show an interesting combination of preferred microstructural, mechanical, electrochemical and biological properties, which make them very promising for Degradable Implant applications.
Dirk Bormann - One of the best experts on this subject based on the ideXlab platform.
-
evaluation of the biocompatibility of two magnesium alloys as Degradable Implant materials in comparison to titanium as non resorbable material in the rabbit
2013Co-Authors: Carolin Hampp, Janin Reifenrath, Dirk Bormann, Nina Angrisani, Janmarten Seitz, Andrea MeyerlindenbergAbstract:Abstract The aim of this study is to compare the biocompatibility of the two magnesium based alloys LAE442 and LANd442 with that of titanium. For this purpose, cylindrical Implants were introduced into the medullary cavity of rabbit's tibiae for 4 and 8 weeks. Animals without any Implant served as a control. In the follow-up, clinical, X-ray and μCT-investigations were performed to evaluate the reactions of the bone towards the Implanted materials. After euthanasia, ex vivo μCT- and histological investigations were performed to verify the results of the in vivo tests. It could be shown that all materials induce changes in the bone. Whereas LANd442 caused the most pronounced reactions, such as increasing bone volume and bone porosity and decreasing bone density, titanium showed the most bone–Implant contact by forming trabeculae. The tibiae of rabbits without Implants also reacted by forming cavities, it is therefore assumed that the surgery method itself influences the bone.
-
magnesium alloys as promising Degradable Implant materials in orthopaedic research
2011Co-Authors: Janin Reifenrath, Dirk Bormann, Andrea MeyerlindenbergAbstract:Magnesium alloys as Degradable Implant materials in orthopaedic research received a lot of interest in recent years (Witte et al., 2007a; Xu et al., 2008; Zhang et al., 2010). The application of resorbable Implant material avoids an Implant removal surgery and therewith helps to diminish the costs and the burden for the patient. In comparison to other Degradable Implant materials like polymers, magnesium alloys excel in higher tensile and compressive strength and the young’s modulus is near to cortical bone (Hofmann, 1995; Staiger et al., 2006; Kaese, 2002). Another advantage that leads to the choice of magnesium alloys as Implant material is the fact, that magnesium is a natural component of the body and furthermore has many important functions within the body (Hartwig, 2001). Magnesium is tested as non-allergenic (Witte et al., 2007a) and due to several studies it is assumed, that it stimulates new bone formation in vitro and in vivo (Revell et al., 2004; Zreitqat et al., 2002; Witte et al., 2007b). For the application as orthopedic Implant material in weight bearing bones, only magnesium alloys with a slow corrosion rate are useful. A high corrosion rate results in gas formation, a too fast loss of mechanical stability and a considerably higher bone remodelling activity (Thomann et al., 2009; Krause et al., 2010). Beside to different coating facilities (Witte et al., 2009; Zhang et al., 2010) and surface treatments (von der Hoh et al., 2006; Hanzi et al., 2008), in particular the alloying of aluminium, lithium, rare earth metals or calcium decrease the corrosion rate in vitro and in vivo (Kaese, 2002; Staiger, 2006; Hanzi et al., 2008; Krause et al., 2010; Thomann et al., 2009). However, in vivo and in vitro corrosion rates can be quite different (Witte et al., 2006; Zhang et al., 2010), which makes it more difficult to develop and adapt magnesium alloys for biomedical use. In order to investigate if the chosen magnesium-alloys are suitable for the use in orthopedic applications, in vivo-studies in rabbit tibiae were conducted. Therefor the selected and in vitro examined magnesium alloys LAE442, WE43, MgCa0.8, AX30, ZEK100 were Implanted into the rabbit tibia and examined with regard to the mechanical stability, the in vivo corrosion rate and the biocompatibility. For the in vivo investigation of the Implant materials, the rabbit was used as established animal model for orthopaedic applications (Pearce, 2007). All animal experiments were conducted under an ethic committee approved protocol in accordance with German federal welfare legislation. Five rabbits were used for each group. Extruded pins with 2.5 mm in
-
degradation behaviour and mechanical properties of magnesium Implants in rabbit tibiae
2010Co-Authors: Annett Krause, Dirk Bormann, Christian Krause, Friedrichwillhelm Bach, Henning Windhagen, Andrea MeyerlindenbergAbstract:To investigate the initial mechanical strength and the degradation behaviour with the associated changes in mechanical properties of magnesium-based osteosynthesis Implants, 30 rabbits were Implanted with cylindrical pins of the alloys MgCa0.8 (magnesium with 0.8 wt% calcium), LAE442 (magnesium with 4 wt% lithium, 4 wt% aluminium and 2 wt% rare earths) and WE43 (magnesium with 4 wt% yttrium and 3 wt% rare earths). The Implants were inserted into the medullary cavity of both tibiae. After 3 and 6 months, each half of the animals was euthanized, respectively, and the Implants were taken out. A determination of volume, three-point bending tests, scanning electron microscopy (SEM) and energy dispersive X-ray analyses as well as metallographic and μ-computed tomography examinations were accomplished. All Implants were clinically well tolerated. MgCa-Implants showed the least initial strength and the highest loss in volume after 6 months. SEM- and μ-computed tomography examinations revealed a pronounced pitting corrosion. Therefore, their use as Degradable Implant material seems to be limited. LAE442 has the best initial strength which seems to be sufficient for an application in weight-bearing bones. The degradation behaviour is very constant. However, possible unknown side effects of the rare earths have to be excluded in further investigations on biocompatibility. Considering all results of WE43, its application as osteosynthesis material for fracture repair is ineligible due to its heterogeneous and unpredictable degradation behaviour.
-
degradation behaviour and mechanical properties of magnesium Implants in rabbit tibiae
2010Co-Authors: Annett Krause, Dirk Bormann, Christian Krause, Friedrichwillhelm Bach, Henning Windhagen, Nina Von Der Hoh, Andrea MeyerlindenbergAbstract:To investigate the initial mechanical strength and the degradation behaviour with the associated changes in mechanical properties of magnesium-based osteosynthesis Implants, 30 rabbits were Implanted with cylindrical pins of the alloys MgCa0.8 (magnesium with 0.8 wt% calcium), LAE442 (magnesium with 4 wt% lithium, 4 wt% aluminium and 2 wt% rare earths) and WE43 (magnesium with 4 wt% yttrium and 3 wt% rare earths). The Implants were inserted into the medullary cavity of both tibiae. After 3 and 6 months, each half of the animals was euthanized, respectively, and the Implants were taken out. A determination of volume, three-point bending tests, scanning electron microscopy (SEM) and energy dispersive X-ray analyses as well as metallographic and μ-computed tomography examinations were accomplished. All Implants were clinically well tolerated. MgCa-Implants showed the least initial strength and the highest loss in volume after 6 months. SEM- and μ-computed tomography examinations revealed a pronounced pitting corrosion. Therefore, their use as Degradable Implant material seems to be limited. LAE442 has the best initial strength which seems to be sufficient for an application in weight-bearing bones. The degradation behaviour is very constant. However, possible unknown side effects of the rare earths have to be excluded in further investigations on biocompatibility. Considering all results of WE43, its application as osteosynthesis material for fracture repair is ineligible due to its heterogeneous and unpredictable degradation behaviour.
F T Cheng - One of the best experts on this subject based on the ideXlab platform.
-
effect of ph on the in vitro corrosion rate of magnesium Degradable Implant material
2010Co-Authors: Wf F Ng, Ky Y Chiu, F T ChengAbstract:Magnesium (Mg) has been recently advocated as a potential metallic material for Degradable bone plates. The corrosion behavior of Mg in body fluids at different pH values, however, has not been fully studied. The pH value of the body fluid at the location of bone fracture changes during the course of recovery, and study of the effect of pH on the corrosion rate of Mg provides important information in the development and design of Mg Implants. In the present study, the corrosion behavior of Mg in Hanks' solution (a simulated body fluid) at pH value ranging from 5.5 to 8.0 was studied via monitoring the rate of hydrogen gas evolution. The experimental results show that the pH value has very large effect on the corrosion rate in Hanks' solution within the range 5.5 to 8.0. The corrosion rate (penetration rate) at pH 5.5 exceeds 800 μm per day, which is extremely high. On the other hand, it drops to about 6 μm and 3 μm per day at pH 7.4 and 8.0, respectively. The corrosion behavior of Mg at different pH values was also studied using electrochemical methods, including potentiodynamic polarization measurement and electrochemical impedance spectroscopy (EIS).
-
characterization and corrosion studies of fluoride conversion coating on Degradable mg Implants
2007Co-Authors: K Y Chiu, F T Cheng, M H Wong, H C ManAbstract:Abstract Fluoride conversion coating was synthesized on magnesium (Mg) by immersion treatment in hydrofluoric acid (HF) at room temperature, with the aim of improving the corrosion resistance of Mg in applications as Degradable Implant material. After an immersion period of 24 h in 48% HF, the samples carried a bronze color, and the conversion coating was dense and free of cracks. Field-emission scanning-electron microscopy (FE-SEM) of the cross-section revealed a coating thickness of about 1.5 μm. Atomic-force microscopy (AFM) recorded an average surface roughness of ∼ 21 nm for the coated sample, similar to that of the untreated one (∼ 17 nm). The coating was mainly composed of magnesium fluoride (MgF 2 ) as identified by thin-film X-ray diffractometry (TF-XRD), consistent with compositional analysis using X-ray photoelectron spectroscopy (XPS). The MgF 2 was in the form of crystallites of a few nm. A small amount of oxygen was present inside the coating, suggesting that some F − ions are replaced by hydroxyl (OH − ) ions in the MgF 2 structure, or that a small amount of Mg(OH) 2 was present. The corrosion resistance of untreated and conversion coated Mg in Hanks' solution was studied using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization tests, and immersion tests. EIS results showed a polarization resistance of 0.18 kΩ cm 2 for the untreated Mg and 5.2 kΩ cm 2 for the coated sample, giving an improvement of about 30 times. Polarization tests also recorded a reduction in corrosion current density from 400 μA/cm 2 to 10 μA/cm 2 , showing an improvement of about 40 times. The galvanic effect between untreated and fluoride-coated Mg samples was small. Immersion tests in Hanks' solution also resulted in a much milder and more uniform corrosion damage on the fluoride-coated samples. The results of the present study showed that fluoride coating by conversion treatment is a simple and promising way of enhancing the corrosion resistance of Mg in Hanks' solution, or that it may be employed as a pretreatment step for subsequent coating.
Annett Krause - One of the best experts on this subject based on the ideXlab platform.
-
degradation behaviour and mechanical properties of magnesium Implants in rabbit tibiae
2010Co-Authors: Annett Krause, Dirk Bormann, Christian Krause, Friedrichwillhelm Bach, Henning Windhagen, Andrea MeyerlindenbergAbstract:To investigate the initial mechanical strength and the degradation behaviour with the associated changes in mechanical properties of magnesium-based osteosynthesis Implants, 30 rabbits were Implanted with cylindrical pins of the alloys MgCa0.8 (magnesium with 0.8 wt% calcium), LAE442 (magnesium with 4 wt% lithium, 4 wt% aluminium and 2 wt% rare earths) and WE43 (magnesium with 4 wt% yttrium and 3 wt% rare earths). The Implants were inserted into the medullary cavity of both tibiae. After 3 and 6 months, each half of the animals was euthanized, respectively, and the Implants were taken out. A determination of volume, three-point bending tests, scanning electron microscopy (SEM) and energy dispersive X-ray analyses as well as metallographic and μ-computed tomography examinations were accomplished. All Implants were clinically well tolerated. MgCa-Implants showed the least initial strength and the highest loss in volume after 6 months. SEM- and μ-computed tomography examinations revealed a pronounced pitting corrosion. Therefore, their use as Degradable Implant material seems to be limited. LAE442 has the best initial strength which seems to be sufficient for an application in weight-bearing bones. The degradation behaviour is very constant. However, possible unknown side effects of the rare earths have to be excluded in further investigations on biocompatibility. Considering all results of WE43, its application as osteosynthesis material for fracture repair is ineligible due to its heterogeneous and unpredictable degradation behaviour.
-
degradation behaviour and mechanical properties of magnesium Implants in rabbit tibiae
2010Co-Authors: Annett Krause, Dirk Bormann, Christian Krause, Friedrichwillhelm Bach, Henning Windhagen, Nina Von Der Hoh, Andrea MeyerlindenbergAbstract:To investigate the initial mechanical strength and the degradation behaviour with the associated changes in mechanical properties of magnesium-based osteosynthesis Implants, 30 rabbits were Implanted with cylindrical pins of the alloys MgCa0.8 (magnesium with 0.8 wt% calcium), LAE442 (magnesium with 4 wt% lithium, 4 wt% aluminium and 2 wt% rare earths) and WE43 (magnesium with 4 wt% yttrium and 3 wt% rare earths). The Implants were inserted into the medullary cavity of both tibiae. After 3 and 6 months, each half of the animals was euthanized, respectively, and the Implants were taken out. A determination of volume, three-point bending tests, scanning electron microscopy (SEM) and energy dispersive X-ray analyses as well as metallographic and μ-computed tomography examinations were accomplished. All Implants were clinically well tolerated. MgCa-Implants showed the least initial strength and the highest loss in volume after 6 months. SEM- and μ-computed tomography examinations revealed a pronounced pitting corrosion. Therefore, their use as Degradable Implant material seems to be limited. LAE442 has the best initial strength which seems to be sufficient for an application in weight-bearing bones. The degradation behaviour is very constant. However, possible unknown side effects of the rare earths have to be excluded in further investigations on biocompatibility. Considering all results of WE43, its application as osteosynthesis material for fracture repair is ineligible due to its heterogeneous and unpredictable degradation behaviour.