In vitro and in vivo studies of Zn-Mn biodegradable metals designed for orthopedic applications

Jiang

Shang

et al. 2021

Biodegradable metals are promising candidates for bone defect repair. With an evidence-based approach, this study investigated and analyzed the performance and degradation properties of biodegradable metals in animal models for bone defect repair to explore their potential clinical translation. Animal studies on bone defect repair with biodegradable metals in comparison with other traditional biomaterials were reviewed. Data was carefully collected after identification of population, intervention, comparison, outcome, and study design (PICOS), and following the inclusion criteria of biodegradable metals in animal studies. 30 publications on pure Mg, Mg alloys, pure Zn and Zn alloys were finally included after extraction from a collected database of 2543 publications. A qualitative systematic review and a quantitative meta-analysis were performed. Given the heterogeneity in animal model, anatomical site and critical size defect (CSD), biodegradable metals exhibited mixed effects on bone defect repair and degradation in animal studies in comparison with traditional non-degradable metals, biodegradable polymers, bioceramics, and autogenous bone grafts. The results indicated that there were limitations in the experimental design of the included studies, and quality of the evidence presented by the studies was very low. To enhance clinical translation of biodegradable metals, evidence-based research with data validity is needed. Future studies should adopt standardized experimental protocols in investigating the effects of biodegradable metals on bone defect repair with animal models.

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Biodegradable metals for bone defect repair: A systematic review and meta-analysis based on animal studies

Jiang

Shang

et al. 2021

“…Thirdly, using the SYBR Premix Ex Taq Ⅱ (2 × ) as PCR reagent, the real-time PCR was conducted on a ABI 7500 Fast machine (Applied Biosystems, Countaboeuf, France), under the conditions as-followed: 95 °C 30s; 95 °C 5s + 60 °C 40s, 40 cycles; dissolution curve, 95 °C 15s + 60 °C 60s + 95 °C 15s. Finally, the results were calculated through the 2 −ΔΔCT method [ 39 ].…”

Section: Methodsmentioning

confidence: 99%

“…However, the mechanical properties of pure Zn is unsatisfactory [ 18 , 19 ]. To enhance the performance of Zn-based biodegradable metals, alloying elements, including Li [ 20 , 21 ], Mg [ [22] , [23] , [24] , [25] , [26] , [27] , [28] ], Ca [ 29 , 30 ], Sr [ 12 , 31 ], Cu [ [32] , [33] , [34] , [35] ], Ag [ [36] , [37] , [38] ], Mn [ [39] , [40] , [41] , [42] ] and Fe [ 43 , 44 ], were introduced into the system. Among these researches, element Li have brought the most significant improvement in mechanical strength [ 45 ].…”

Section: Introductionmentioning

confidence: 99%

Biodegradable ZnLiCa ternary alloys for critical-sized bone defect regeneration at load-bearing sites: In vitro and in vivo studies

Jia

Yang

et al. 2021

Self Cite

A novel biodegradable metal system, ZnLiCa ternary alloys, were systematically investigated both in vitro and in vivo . The ultimate tensile strength (UTS) of Zn0.8Li0.1Ca alloy reached 567.60 ± 9.56 MPa, which is comparable to pure Ti, one of the most common material used in orthopedics. The elongation of Zn0.8Li0.1Ca is 27.82 ± 18.35%, which is the highest among the ZnLiCa alloys. The in vitro degradation rate of Zn0.8Li0.1Ca alloy in simulated body fluid (SBF) showed significant acceleration than that of pure Zn. CCK-8 tests and hemocompatibility tests manifested that ZnLiCa alloys exhibit good biocompatibility. Real-time PCR showed that Zn0.8Li0.1Ca alloy successfully stimulated the expressions of osteogenesis-related genes (ALP, COL-1, OCN and Runx-2), especially the OCN. An in vivo implantation was conducted in the radius of New Zealand rabbits for 24 weeks, aiming to treat the bone defects. The Micro-CT and histological evaluations proved that the regeneration of bone defect was faster within the Zn0.8Li0.1Ca alloy scaffold than the pure Ti scaffold. Zn0.8Li0.1Ca alloy showed great potential to be applied in orthopedics, especially in the load-bearing sites.

“…On the other hand, Zn and its alloys exhibit a moderate degradation rate, compared to Fe and Mg, and the degradation products released do not contain hydrogen [ 9 , 20 ]. More importantly, the potential osteoinductive ability of Zn and Zn-based materials has been demonstrated [ [21] , [22] , [23] ]. Nevertheless, the limitation of as-cast pure zinc is its insufficient mechanical properties concerning most medical implants, i.e.…”

Section: Introductionmentioning

confidence: 99%

Appropriately adapted properties of hot-extruded Zn–0.5Cu–xFe alloys aimed for biodegradable guided bone regeneration membrane application

Li²,

Shen

et al. 2021

Appropriately adapted comprehensive mechanical properties, degradation behavior and biocompatibility are prerequisites for the application of Zn-based biodegradable implants. In this study, hot-extruded Zn–0.5Cu–xFe (x = 0.1, 0.2 and 0.4 wt%) alloys were fabricated as candidates for biodegradable materials for guided bone regeneration (GBR) membranes. The hot-extrusion process and Cu alloying were expected mostly to enhance the mechanical properties, and the Fe alloying was added mainly for regulating the degradation. The microstructure, mechanical properties and in vitro degradation behavior were systematically investigated. The ZnCuFe alloys were composed of a Zn matrix and FeZn 13 phase. With increasing Fe content, a higher FeZn 13 phase precipitation with larger particles was observed. Since elongation declined significantly until fracture with increasing Fe content up to 0.4 wt%, the ZnCuFe (0.2 wt%) alloy achieved a good balance between mechanical strength and ductility, with an ultimate tensile strength of 202.3 MPa and elongation at fracture of 41.2%. Moreover, the addition of Fe successfully accelerated the degradation of ZnCuFe alloys. The ZnCuFe (0.2 wt%) alloy showed relatively uniform corrosion in the long-term degradation test. Furthermore, extracts of the ZnCuFe (0.2 wt%) alloy showed no apparent cytotoxic effects against L929 fibroblasts, Saos-2 osteoblasts or TAg periosteal cells. The ZnCuFe (0.2 wt%) alloy exhibited the potential to inhibit bacterial adhesion of Streptococcus gordonii and mixed oral bacteria. Our study provides evidence that the ZnCuFe (0.2 wt%) alloy can represent a promising material for the application as a suitable GBR membrane.