Biodegradable magnesium wire promotes regeneration of compressed sciatic nerves

Magnesium（Mg） wire has been shown to be biodegradable and have anti-inflammatory properties. It can induce Schwann cells to secrete nerve growth factor and promote the regeneration of nerve axons after central nervous system injury. We hypothesized that biodegradable Mg wire may enhance compressed peripheral nerve regeneration. A rat acute sciatic nerve compression model was made, and AZ31 Mg wire（3 mm diameter; 8 mm length） bridged at both ends of the nerve. Our results demonstrate that sciatic functional index, nerve growth factor, p75 neurotrophin receptor, and tyrosine receptor kinase A m RNA expression are increased by Mg wire in Mg model. The numbers of cross section nerve fibers and regenerating axons were also increased. Sciatic nerve function was improved and the myelinated axon number was increased in injured sciatic nerve following Mg treatment. Immunofluorescence histopathology showed that there were increased vigorous axonal regeneration and myelin sheath coverage in injured sciatic nerve after Mg treatment. Our findings confirm that biodegradable Mg wire can promote the regeneration of acute compressed sciatic nerves.

Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications

Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding durations.The oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the matrix.The oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding duration.The matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) precipitates.The precipitates almost disappeared in the transition layer.Enhanced passivation effect was observed in the samples treated by a suitable high temperature oxidation.The original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day immersion.The casted and solution treated samples lost roughly half of the weight after 28-day immersion.The high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day immersion.The substantially improved corrosion resistance was contributed to the gradient structure at the surface.On one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of precipitates.Overall,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.

Bio-inspired barnacle cement coating of biodegradable magnesium alloy for cerebrovascular application

Ischemic stroke is increasing worldwide,and stent intervention has gradually become one of the effective treatments.Owing to its good mechanical properties and biocompatibility,biodegradable Mg-Zn-Y-Nd alloy(ZE21B)has good application prospects in vascular stents.However,too fast degradation and delayed endothelialization are the bottleneck problem to limit its further application.In this study,the bio-inspired coating barnacle cement cp19k is constructed on ZE21B surface through electrostatic spraying to improve the corrosion resistance and pro-endothelialization ability.The coating was evaluated through electrochemistry,static immersion corrosion,in vitro blood experiments and cell experiments.Cp19k effectively improved the corrosion resistance of the substrate ZE21B,reduced the degradation rate,improved endothelial cell proliferation and migration capabilities,inhibited smooth muscle cells proliferation and regulated contractile phenotype,inhibited macrophage adhesion,regulated macrophage M2 phenotype,and reduced the expression of inflammatory factor of TNF-a and inhibited fibroplasia in vivo.Our data indicated that the barnacle cement cp19k coating had potential application on the surface modification of Mg alloy cerebrovascular stent.

Surface Modification on Biodegradable Magnesium Alloys as Orthopedic Implant Materials to Improve the Bio-adaptability:A Review

Magnesium （Mg） and its alloys as a novel kind of biodegradable material have attracted much funda- mental research and valuable exploration to develop its clinical application, Mg alloys degrade too fast at the early stage after implantation, thus commonly leading to some problems such as osteolysis, early fast mechanical loss, hydric bubble aggregation, gap formation between the implants and the tissue. Surface modification is one of the effective methods to control the degradation property of Mg alloys to adapt to the need of organism. Some coatings with bioactive elements have been developed, especially for the micro-arc oxidation coating, which has high adhesion strength and can be added with Ca, P, and Sr elements. Chemical deposition coating including bio-mimetic deposition coating, electro-deposition coating and chemical conversion coating can provide good anticorrosion property as well as better bioactivity with higher Ca and P content in the coating. From the biodegradation study, it can be seen that surface coating protected the Mg alloys at the early stage providing the Mg alloy substrate with lower degra-dation rate. The biocompatibility study showed that the surface modification could provide the cell and tissue stable and weak alkaline surface micro-environment adapting to the cell adhesion and tissue growth. The surface modification also decreased the mechanical loss at the early stage adapting to the load- bearing requirement at this stage. From the interface strength between Mg alloys implants and the surrounding tissue study, it can be seen that the surface modification improved the bio-adhesion of Mg alloys with the surrounding tissue, which is believed to be contributed to the tissue adaptability of the surface modification. Therefore, the surface modification adapts the biodegradable magnesium alloys to the need of hiodegradation, biocompatibility and mechanical loss property. For the different clinical application, different surface modification methods can be provided to adapt to the clinical requirements for the Mg alloy implants.

Research and development strategy for biodegradable magnesium-based vascular stents:a review

Magnesium alloys are an ideal material for biodegradable vascular stents,which can be completely absorbed in the human body,and have good biosafety and mechanical properties.However,the rapid corrosion rate and excessive localized corrosion,as well as challenges in the preparation and processing of microtubes for stents,are restricting the clinical application of magnesium-based vascular stents.In the present work we will give an overview of the recent progresses on biodegradable magnesium based vascular stents including magnesium alloy design,high-precision microtubes processing,stent shape optimisation and functional coating preparation.In particular,the Triune Principle in biodegradable magnesium alloy design is proposed based on our research experience,which requires three key aspects to be considered when designing new biodegradable magnesium alloys for vascular stents application,i.e.biocompatibility and biosafety,mechanical properties,and biodegradation.This review hopes to inspire the future studies on the design and development of biodegradable magnesium alloy-based vascular stents.

Zinc-doped hydroxyapatite-zeolite/polycaprolactone composites coating on magnesium substrate for enhancing in-vitro corrosion and antibacterial performance

This work is focused on developing zinc-doped hydroxyapatite-zeolite(Zn HA-Zeo)and polycaprolactone(PCL)composite coatings on magnesium(Mg)substrate to improve the corrosion resistance and antimicrobial properties.Dip-coating technique was used to coat Zn HA-Zeo/PCL on the Mg substrate at room temperature.The samples were subjected to field emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),Fourier transform infrared(FTIR),energy dispersive X-ray spectroscopy(EDX)and antimicrobial potential.Results demonstrated that composite coatings consist of HA,scholzite,zeolite,and PCL phases.EDX spectra indicated the presence of calcium(Ca),silicon(Si),aluminum(Al),zinc(Zn),phosphorus(P)and oxygen(O).The composite surface appeared in spherical-like microstructure on coating with thickness ranging 226-260μm.Zinc-doped HA-Zeo composite coating had a high corrosion resistance and provided sufficient protection to the Mg surface against galvanic corrosion.Doped Zn HA-Zeo coating samples exhibited superior disc inhibition by confirming antimicrobial activity against the E.coli as compared to HA-Zeo sample.Altogether these results showed that the Zn HA-Zeo coatings not only improved the corrosion resistance,but also enhanced the antimicrobial property and hence they can be used as suitable candidates for implant applications.

Preparation and characterization of Ca-P coating on AZ31 magnesium alloy

A Ca-P coating consisting of biodegradableβ-tricalcium phosphate[β-TCP,β-Ca3(PO4)2]accepted for medical application was coated on a biodegradable AZ31 alloy by chemical deposition to improve the corrosion resistance.The good bonding strength of the coating is obtained.The results show that the corrosion potential of the Ca-P coated AZ31 alloy increases significantly,and MG63 cells show good adherence,proliferation and differentiation on the surface of the coated alloy.The Ca-P coating might be an effective way to improve the surface bioactivity of magnesium alloys.

Additive manufacturing of porous magnesium alloys for biodegradable orthopedic implants:Process,design,and modification

Biodegradable magnesium(Mg)alloys exhibit excellent biocompatibility,adequate mechanical properties,and osteogenic effect.They can contribute to complete recovery of damaged tissues without concerns about a second surgery and have achieved clinical applications in orthopedic and cardiovascular fields.Porous scaffolds can provide functions such as bone integration and adjustable mechanical properties,thus widely used for bone repair.Additive manufacturing(AM)offers the advantages of design freedom and high precision,enabling the reliable production of porous scaffolds with customized structures.The combination of biodegradable Mg alloys,porous scaffolds,and AM processes has created tremendous opportunities for the precision treatment of bone defects.This article reviews the current development in the additive manufacturing process and design of Mg alloy biodegradable orthopedic implants,fo-cusing on chemical compositions,structural design,surface treatment,and their effects on mechanical properties,degradation behavior,and biocompatibility.Finally,the future perspective of porous Mg alloy biodegradable orthopedic implants is proposed.

Effect of heat treatment on microstructure, mechanical properties and in vitro degradation behavior of as-extruded Mg-2.7Nd-0.2Zn-0.4Zr alloy

Mg-2.7Nd-0.2Zn-0.4Zr （mass fraction, %） alloy was designed for degradable biomedical material. The ingots of the alloy were solution treated and then hot extruded. The extruded rods were heat treated with aging treatment, solution treatment and solution＋aging treatment, respectively. Microstructures of the alloy were observed by optical microscopy （OM） and scanning electron microscopy （SEM）. Mechanical properties at room temperature were tested. In vitro degradation behavior of the alloy immersed in simulated body fluid was measured by hydrogen evolution and mass loss tests. The degradation morphologies of the alloy with and without degradation products were observed by SEM. The results show that the grains grow apparently after solution treatment. Solution treatment improves the elongation of as-extruded alloy significantly and decreases the strength, while aging treatment improves the strength and reduces the elongation of the alloy. The yield ratio is reduced by heat treatment. The in vitro degradation results of the alloy show that solution treatment on the as-extruded alloy results in a little higher degradation rate and aging treatment on the alloy can reduce degradation rate slightly.

Electrochemical noise analysis on the pit corrosion susceptibility of biodegradable AZ31 magnesium alloy in four types of simulated body solutions

Magnesium alloys have been investigated as biodegradable implant materials since the last century. Non-uniform degradation caused by local corrosion limits their application, and no appropriate technology has been used in the research. In this study, electrochemical noise has been used to study the pit corrosion on magnesium alloy AZ31 in four types of simulated body solutions, and the data have been analyzed using wavelet analysis and stochastic theory. Combining these with the conventional polarization curves, mass loss tests and scanning electron microscopy, the electrochemical noise results implied that AZ31 alloy in normal saline has the fastest corrosion rate, a high pit initiation rate, and maximum pit growth probability. In Hanks＇ balanced salt solution and phosphate-buffered saline, AZ31 alloy has a high pit initiation rate and larger pit growth probability, while in simulated body fluid, AZ31 alloy has the slowest corrosion rate, lowest pit initiation rate and smallest pit growth probability.

Corrosion fatigue of the extruded Mg-Zn-Y-Nd alloy in simulated body fluid

Magnesium alloys were considered to be used as biodegradable implants due to their biocompatibility,biodegradability and nontoxicity.However,under the simultaneous action of corrosive environment and mechanical loading in human body,magnesium alloys are easy to be affected by corrosion fatigue and stress corrosion cracking.In this work,the fatigue behavior of the extruded Mg-Zn-Y-Nd alloy used for vascular stents was studied both in air and in simulated body fluid(SBF).It was revealed that the fatigue limit of as-extruded Mg-Zn-Y-Nd alloy in air is about 65 MPa at 10^7 cycles,while there is no limit in SBF and shows a linear relationship between the fatigue life and stress amplitudes.The fatigue crack source in air was formed by the inclusions and defects.However,the stress corrosion and hydrogen embrittlement are the main reasons for the formation of the fatigue initial crack source in SBF.

Magnesium Alloy for Repair of Lateral Tibial Plateau Defect in Minipig Model

Bone graft substitutes are widely-studied as alternatives to bone grafts in the clinic. The currently available products are mostly ceramics and polymers. Considerable progress has been made in the study of the biodegradable magnesium alloys, which possess the necessary attributions of a suitable substitute, including an excellent mechanical property. In the present study, a minipig model of a lateral tibial plateau defect was used to evaluate the effectiveness of a magnesium alloy in the repair of a critical-sized defect. The micro-arc oxidation （MAO）-coated ZK60 alloy tablets and medical-grade calcium sulfate pellets were used as the test and control materials, respectively. Bone morphology was monitored by computed tomography after the implantation for 2 and 4 months. It was found that the bone morphology in minipigs following magnesium treatment was similar to that of the normal bone, whereas an abnormal and concave morphology was displayed following the calcium sulfate treatment. The average bone healing rate for the magnesium-treated defects was higher than that of the calcium sulfate-treated defects at the first 4 months following the implantation. Overall, magnesium treatment appeared to calcium sulfate treatment. Thus, the MAO-coated ZK60 al substitute, and further research on its biological activity in improve the defect repair as compared with the oy appears to be a useful biocompatible bone graft vivo is needed.

Controlled release of hydrogen by implantation of magnesium induces P53-mediated tumor cells apoptosis

Hydrogen has been used to suppress tumor growth with considerable efficacy.Inhalation of hydrogen gas and oral ingestion of hydrogen-rich saline are two common systemic routes of hydrogen administration.We have developed a topical delivery method of hydrogen at targeted sites through the degradation of magnesium-based biomaterials.However,the underlying mechanism of hydrogen’s role in cancer treatment remains ambiguous.Here,we investigate the mechanism of tumor cell apoptosis triggered by the hydrogen released from magnesium-based biomaterials.We find that the localized release of hydrogen increases the expression level of P53 tumor suppressor proteins,as demonstrated by the in vitro RNA sequencing and protein expression analysis.Then,the P53 proteins disrupt the membrane potential of mitochondria,activate autophagy,suppress the reactive oxygen species in cancer cells,and finally result in tumor suppression.The anti-tumor efficacy of magnesium-based biomaterials is further validated in vivo by inserting magnesium wire into the subcutaneous tumor in a mouse.We also discovered that the minimal hydrogen concentration from magnesium wires to trigger substantial tumor apoptosis is 91.2μL/mm^(3)per day,which is much lower than that required for hydrogen inhalation.Taken together,these findings reveal the release of H2 from magnesium-based biomaterial exerts its anti-tumoral activity by activating the P53-mediated lysosome-mitochondria apoptosis signaling pathway,which strengthens the therapeutic potential of this biomaterial as localized anti-tumor treatment.

Black Mn-containing layered double hydroxide coated magnesium alloy for osteosarcoma therapy, bacteria killing, and bone regeneration

Osteosarcoma (OS) tissue resection with distinctive bactericidal activity, followed by regeneration of bone de-fects, is a highly demanded clinical treatment. Biodegradable Mg-based implants with desirable osteopromotive and superior mechanical properties to polymers and ceramics are promising new platforms for treating bone-related diseases. Integration of biodegradation control, osteosarcoma destruction, anti-bacteria, and bone defect regeneration abilities on Mg-based implants by applying biosafe and facile strategy is a promising and challenging topic. Here, a black Mn-containing layered double hydroxide (LDH) nanosheet-modified Mg-based implants was developed. Benefiting from the distinctive capabilities of the constructed black LDH film, including near-infrared optical absorption and reactive oxygen species (ROS) generation in a tumor-specific microenvi-ronment, the tumor cells and tissue could be effectively eliminated. Concomitant bacteria could be killed by localized hyperthermia. Furthermore, the enhanced corrosion resistance and synergistic biofunctions of Mn and Mg ions of the constructed black LDH-modified Mg implants significantly facilitated cell adhesion, spreading and proliferation and osteogenic differentiation in vitro, and accelerated bone regeneration in vivo. This work offers a new platform and feasible strategy for OS therapeutics and bone defect regeneration, which broadens the biomedical application of Mg-based alloys.

Microstructure, Mechanical Properties, Corrosion Behavior and Biocompatibility of As-Extruded Biodegradable Mg–3Sn–1Zn–0.5Mn Alloy

The microstructure evolution and mechanical properties of biodegradable Mg-3Sn-1Zn-0.5Mn alloys were investigated by the optical microscopy, X-ray diffractometer and a universal material testing machine. The corrosion and degradation behaviors were studied by potentiodynamic polarization method and immersion test in a simulated body fluid （SBF）. It was found that the as-extruded Mg-3Sn-1Zn-0.5Mn alloy has the fine equiaxed grains which underwent complete dynamic recrystallization during the hot extrusion process, with the second phase particles of Mg2Sn precipitated on the grain boundaries and inside the grains. The tensile strength and elongation of as-extruded Mg-3Sn-1Zn-0.5Mn alloys were 244 ± 3.7 MPa and 19.3% ± 1.7%, respectively. The potentiodynamic polarization curves in SBF solution indicated the better corrosion resistance of the as-extruded Mg-3Sn-1Zn-0.5Mn alloy in the SBF solution. Immersion test in the SBF solution for 720 h revealed that the corrosion rate of as-extruded Mg-3Sn-1Zn-0.5Mn alloy was nearly 4±0.33 ram/year. The hemolysis rate of as-extruded Mg-3Sn-1Zn-0.5Mn alloy was lower than the safe value of 5% according to ISO 10993-4. As-extruded Mg-3Sn- 1Zn-0.5Mn alloy showed good biocompatibility after being implanted into the dorsal muscle and the femoral shaft of the rabbit, and no abnormalities were found after short-term implantation. It was revealed that the as-extruded Mg-3Sn-1Zn-0.5Mn alloy is a promising material for biodegradable implants, which possesses an interesting combination of preferred mechanical properties, better corrosion resistance and biocompatibility.

Design of single-phased magnesium alloys with typically high solubility rare earth elements for biomedical applications:Concept and proof

Rare earth elements(REEs)have been long applied in magnesium alloys,among which the mischmetal-containing WE43 alloy has already got the CE mark approval for clinical application.A considerable amount of REEs(7 wt%)is needed in that multi-phased alloy to achieve a good combination of mechanical strength and corrosion resistance.However,the high complex RE addition accompanied with multiple second phases may bring the concern of biological hazards.Single-phased Mg-RE alloys with simpler compositions were proposed to improve the overall performance,i.e.,“Simpler alloy,better performance”.The single-phased microstructure can be successfully obtained with typical high-solubility REEs(Ho,Er or Lu)through traditional smelting,casting and extrusion in a wide compositional range.A good corrosion resistance with a macroscopically uniform corrosion mode was guaranteed by the homogeneously single-phased microstructure.The bimodal-grained structure with plenty of sub-grain microstructures allow us to minimize the RE addition to<1 wt%,without losing mechanical properties.The single-phased Mg-RE alloys show comparable mechanical properties to the clinically-proven Mg-based implants.They exhibited similar in-vitro and in-vivo performances(without local or systematic toxicity in SD-rats)compared to a high purity magnesium.In addition,metal elements in our single-phased alloys can be gradually excreted through the urinary system and digestive system,showing no consistent accumulation of RE in main organs,i.e.,less burden on organs.The novel concept in this study focuses on the simplification of Mg-RE based alloys for biomedical purpose,and other biodegradable metals with single-phased microstructures are expected to be explored.

Sustained release of magnesium and zinc ions synergistically accelerates wound healing

Skin wounds are a major medical challenge that threaten human health.Functional hydrogel dressings demonstrate great potential to promote wound healing.In this study,magnesium(Mg)and zinc(Zn)are introduced into methacrylate gelatin(GelMA)hydrogel via low-temperature magnetic stirring and photocuring,and their effects on skin wounds and the underlying mechanisms are investigated.Degradation testing confirmed that the GelMA/Mg/Zn hydrogel released magnesium ions(Mg^(2+))and zinc ions(Zn^(2+))in a sustained manner.The Mg^(2+) and Zn^(2+)not only enhanced the migration of human skin fibroblasts(HSFs)and human immortalized keratinocytes(HaCats),but also promoted the transformation of HSFs into myofibroblasts and accelerated the production and remodeling of extracellular matrix.Moreover,the GelMA/Mg/Zn hydrogel enhanced the healing of full-thickness skin defects in rats via accelerated collagen deposition,angiogenesis and skin wound re-epithelialization.We also identified the mechanisms through which GelMA/Mg/Zn hydrogel promoted wound healing:the Mg^(2+) promoted Zn^(2+)entry into HSFs and increased the concentration of Zn^(2+)in HSFs,which effectively induced HSFs to differentiate into myofibroblasts by activating the STAT3 signaling pathway.The synergistic effect of Mg^(2+) and Zn^(2+)promoted wound healing.In conclusion,our study provides a promising strategy for skin wounds regeneration.

AZ91 Magnesium Alloy/Porous Hydroxyapatite Composite for Potential Application in Bone Repair

AZ91/HA composite was prepared by AZ91 magnesium alloy and porous HA using squeeze casting method. The microstructure and mechanical property of the AZ91/HA composite were studied. The results show that the molten AZ91 alloy completely infiltrated the preform without destroying the porous structure of the HA preform. The compressive strength of AZ91/HA composite increased significantly compared with that of the porous HA. The immersion test indicated that AzgI ahoy shows a lower corrosion resistance and is easier to be corroded in comparison with HA.

In vitro and in vivo study on fine-grained Mg-Zn-RE-Zr alloy as a biodegradeable orthopedic implant produced by friction stir processing

Magnesium alloys containing biocompatible components show tremendous promise for applications as temporary biomedical devices. However, to ensure their safe use as biodegradeable implants, it is essential to control their corrosion rates. In concentrated Mg alloys, a microgalvanic coupling between the α-Mg matrix and secondary precipitates exists which results in increased corrosion rate. To address this challenge, we engineered the microstructure of a biodegradable Mg-Zn-RE-Zr alloy by friction stir processing (FSP), improving its corrosion resistance and mechanical properties simultaneously. The FS processed alloy with refined grains and broken and uniformly distributed secondary precipitates showed a relatively uniform corrosion morphology accompanied with the formation of a stable passive layer on the alloy surface. In vivo corrosion evaluation of the processed alloy in a small animal model showed that the material was well-tolerated with no signs of inflammation or harmful by-products. Remarkably, the processed alloy supported bone until it healed till eight weeks with a low in vivo corrosion rate of 0.7 mm/year. Moreover, we analyzed blood and histology of the critical organs such as liver and kidney, which showed normal functionality and consistent ion and enzyme levels, throughout the 12- week study period. These results demonstrate that the processed Mg-Zn-RE-Zr alloy offers promising potential for osseointegration in bone tissue healing while also exhibiting controlled biodegradability due to its engineered microstructure. The results from the present study will have profound benefit for bone fracture management, particularly in pediatric and elderly patients.

Multiscale morphological analysis of bone microarchitecture around Mg-10Gd implants

The utilization of biodegradable magnesium(Mg)-based implants for restoration of bone function following trauma represents a transformative approach in orthopaedic application.One such alloy,magnesium-10 weight percent gadolinium(Mg-10Gd),has been specifically developed to address the rapid degradation of Mg while enhancing its mechanical properties to promote bone healing.Previous studies have demonstrated that Mg-10Gd exhibits favorable osseointegration;however,it exhibits distinct ultrastructural adaptation in comparison to conventional implants like titanium(Ti).A crucial aspect that remains unexplored is the impact of Mg-10Gd degradation on the bone microarchitecture.To address this,we employed hierarchical three-dimensional imaging using synchrotron radiation in conjunction with image-based finite element modelling.By using the methods outlined,the vascular porosity,lacunar porosity and the lacunar-canaliculi network(LCN)morphology of bone around Mg-10Gd in comparison to Ti in a rat model from 4 weeks to 20 weeks post-implantation was investigated.Our investigation revealed that within our observation period,the degradation of Mg-10Gd implants was associated with significantly lower(p<0.05)lacunar density in the surrounding bone,compared to Ti.Remarkably,the LCN morphology and the fluid flow analysis did not significantly differ for both implant types.In summary,a more pronounced lower lacunae distribution rather than their morphological changes was detected in the surrounding bone upon the degradation of Mg-10Gd implants.This implies potential disparities in bone remodelling rates when compared to Ti implants.Our findings shed light on the intricate relationship between Mg-10Gd degradation and bone microarchitecture,contributing to a deeper understanding of the implications for successful osseointegration.