Repair Of Defects Research Articles

Pilot Validation of a 3-Dimensional Printed Pituitary Adenoma, Vascular Injury, and Cerebrospinal Fluid Leak Surgical Simulator.

Endoscopic skull base surgery is a subspecialty field which would benefit significantly from high-fidelity surgical simulators. Giving trainees the opportunity to flatten their learning curve by practicing a variety of procedures on surgical simulators will inevitably improve patient outcomes. Four neurosurgeons, 8 otolarynologists, and 6 expert course faculty agreed to participate. All participants were asked to perform a transsphenoidal exposure and resection of a pituitary adenoma, repair a cerebrospinal fluid (CSF) leak, control a carotid injury, and repair a skull base defect. The content, face, and construct validity of the 3-dimensional printed model was examined. The heart rate of the participants significantly increased from baseline when starting the carotid injury simulation (mean 90 vs 121, P = .029) and significantly decreased once the injury was controlled (mean 121 vs 110, P = .033, respectively). The participants reported a significant improvement in anxiety in facing a major vascular injury, as well as an increase in their confidence in management of major vascular injury, resecting a pituitary adenoma and repair of a CSF leak using a 5-point Likert scale (mean 4.42 vs 3.58 P = .05, 2 vs 3.25 P < .001, 2.36 vs 4.27 P < .001 and 2.45 vs 4.0 P = .001, respectively). The mean Objective Structured Assessment of Technical Skills score for experienced stations was 4.4, significantly higher than the Objective Structured Assessment of Technical Skills score for inexperienced stations (mean 3.65, P = .016). We have demonstrated for the first time a validated 3-dimensional printed surgical simulator for endoscopic pituitary surgery that allows surgeons to practice a transsphenoidal approach, surgical resection of a pituitary adenoma, repair of a CSF leak in the diaphragma sellae, control of a carotid injury, and repair of skull base defect.

Sr-Incorporated Bioactive Glass Remodels the Immunological Microenvironment by Enhancing the Mitochondrial Function of Macrophage via the PI3K/AKT/mTOR Signaling Pathway.

The repair of critical-sized bone defects continues to pose a challenge in clinics. Strontium (Sr), recognized for its function in bone metabolism regulation, has shown potential in bone repair. However, the underlying mechanism through which Sr2+ guided favorable osteogenesis by modulating macrophages remains unclear, limiting their application in the design of bone biomaterials. Herein, Sr-incorporated bioactive glass (SrBG) was synthesized for further investigation. The release of Sr ions enhanced the immunomodulatory properties and osteogenic potential by modulating the polarization of macrophages toward the M2 phenotype. In vivo, a 3D-printed SrBG scaffold was fabricated and showed consistently improved bone regeneration by creating a prohealing immunological microenvironment. RNA sequencing was performed to explore the underlying mechanisms. It was found that Sr ions might enhance the mitochondrial function of macrophage by activating PI3K/AKT/mTOR signaling, thereby favoring osteogenesis. Our findings demonstrate the relationship between the immunomodulatory role of Sr ions and the mitochondrial function of macrophages. By focusing on the mitochondrial function of macrophages, Sr2+-mediated immunomodulation sheds light on the future design of biomaterials for tissue regenerative engineering.

Urine high–sensitive troponin I in children cannot offer an applicable alternative to serum

IntroductionIn children, congenital heart defects represent the primary cause of increased serum troponin I. The elimination process of cardiac troponin I from the bloodstream and the factors influencing this process remain unknown. The objective of this study was to explore the role of troponin I as an indicator of cardiac damage in children both in serum and urine, a concept previously investigated in adults.MethodsOur prospective study involved 70 children under 24 months of age. The first group underwent ventricular septal defect repair, while the second group involved children who had undergone partial cavopulmonary anastomosis. For these groups, urine and serum troponin I were assessed on four occasions. The third group, consisting of healthy children, underwent a single measurement of urine troponin I.ResultsSerum troponin I values exhibited an expected elevation in the early postoperative period, followed by a return to lower levels. Significantly higher concentrations of serum troponin I were observed in the first group of children (p &amp;lt; 0.05). A positive correlation was found between troponin I in the first three measurements and cardiopulmonary bypass and aortic cross-clamping time. There was no discernible increase in urine troponin I directly related to myocardial damage; troponin I couldn't be detected in most urine samples.DiscussionThe inability to detect troponin I in urine remains unexplained. Potential explanatory factors may include the isoelectric point of troponin I, elevated urinary concentrations of salts and urea, variations in urine acidity (different pH levels), and a relatively low protein concentration in urine.

Nucleolar Localization of the RNA Helicase DDX21 Predicts Survival Outcomes in Gynecological Cancers.

Cancer cells with DNA repair defects (e.g., BRCA1/2 mutant cells) are vulnerable to PARP inhibitors (PARPi) due to induction of synthetic lethality. However, recent clinical evidence has shown that PARPi can prevent the growth of some cancers irrespective of their BRCA1/2 status, suggesting alternative mechanisms of action. We previously discovered one such mechanism in breast cancer involving DDX21, an RNA helicase that localizes to the nucleoli of cells and is a target of PARP1. We have now extended this observation in endometrial and ovarian cancers and provided links to patient outcomes. When PARP1-mediated ADPRylation of DDX21 is inhibited by niraparib, DDX21 is mislocalized to the nucleoplasm resulting in decreased rDNA transcription, which leads to a reduction in ribosome biogenesis, protein translation, and ultimately endometrial and ovarian cancer cell growth. High PARP1 expression was associated with high nucleolar localization of DDX21 in both cancers. High nucleolar DDX21 negatively correlated with calculated IC50s for niraparib. By studying endometrial cancer patient samples, we were able to show that high DDX21 nucleolar localization was significantly associated with decreased survival. Our study suggests that the use of PARP inhibitors as a cancer therapeutic can be expanded to further types of cancers and that DDX21 localization can potentially be used as a prognostic factor and as a biomarker for response to PARPi.

Management of Pulmonary Vascular Disease Associated with Congenital Left to Right Shunts: A Single Center Experience.

To describe the course and outcomes of children under 18 with left-to-right (LR) shunts and pulmonary arterial hypertension (PAH) undergoing one of two management approaches: PAH treatment prior to LR shunt repair (Treat First) and LR shunt repair first, with or without subsequent PAH treatment (Repair First). Retrospective single center study, conducted from September 2015 to September 2021, of children LR shunts and PAH (defined as indexed pulmonary vascular resistance (PVRi) ≥ 4WU*m2) but without Eisenmenger physiology. Patient characteristics, longitudinal hemodynamics data, PAH management, LR shunt repair, and outcomes were reviewed. Of 768 patients evaluated for LR shunt closure, 51 (6.8%) had LR shunt associated PAH [median age 1.1 (0.37,5) years, median PVRi 6 (5.2,8.7) WU*m2]. Of the "Treat First" group (n=33, 65%), 27 (82%) underwent LR shunt closure and 6 (18%) did not respond to PAH therapy and did not undergo LR shunt closure. In the "Repair First" group (n=18, 35%), 12 (67%) received PAH therapy and 6 (33%) did not. Mortality rates were 6% in "Treat First" and 11% in "Repair First", follow-up of 3.4 and 2.5 years, respectively. After LR shunt closure, there was no significant change in PVRi over a median follow-up of 2 years after surgery (p=0.77). In children with LR shunts and associated PAH, treatment with PAH-targeted therapy before defect repair does not appear to endanger the subjects and may have some benefit. The response to PAH-targeted therapy before shunt closure persists 2-3 years post-closure, providing valuable insights into the long-term management of these patients.

Integration of BMP-2/PLGA microspheres with the 3D printed PLGA/CaSO4 scaffold enhances bone regeneration

Treatment of large and complex irregular bone defects is a major clinical challenge in orthopedic surgery. The current treatment includes bone transportation using the Ilizarov technique and bone cement repair using the Masquelet technique, but they require long-term manual intervention or secondary operation. To improve this situation, we compared the different implanting materials in the literature published in the past 10 years, finding that glycolic acid copolymer (PLGA) and Calcium sulfate (CaSO4) are appropriated to be used as synthetic bone materials due to their advantages of easy-availability, nontoxicity, osteogenic properties and rapid degradation. Meanwhile, the development of 3D printing technique and devices makes it relatively easier to synthetize customized bio-mimetic porous scaffolds, thus facilitating the release of modified protein. In this study, we compounded BMP-2/PLGA microspheres with polylactic glycolic acid copolymer/CaSO4 (PC) 3D printed scaffold to improve the osteogenic properties of the scaffold. The result of our in vitro experiment demonstrated that the prepared PCB scaffold not only had satisfactory bio-compatibility, but also promoted osteogenic differentiation. This 3D printed scaffold is capable to accelerate the repair of complex bone defects by promoting new bone formation, suggesting that it may prove to be a potential bone tissue engineering substitute.

Recent advances in micro-pixel light emitting diode technology

Display technology has developed rapidly in recent years, with III–V system-based micro-light-emitting diodes (μLEDs) attracting attention as a means to overcome the physical limitations of current display systems related to their lifetime, brightness, contrast ratio, response time, and pixel size. However, for μLED displays to be successfully commercialized, their technical shortcomings need to be addressed. This review comprehensively discusses important issues associated with μLEDs, including the use of the ABC model for interpreting their behavior, size-dependent degradation mechanisms, methods for improving their efficiency, novel epitaxial structures, the development of red μLEDs, advanced transfer techniques for production, and the detection and repair of defects. Finally, industrial efforts to commercialize μLED displays are summarized. This review thus provides important insights into the potential realization of next-generation display systems based on μLEDs.

Strategies to improve the performance of polyetheretherketone (PEEK) as orthopedic implants: from surface modification to addition of bioactive materials.

Polyetheretherketone (PEEK), as a high-performance polymer, is widely used for bone defect repair due to its homogeneous modulus of elasticity of human bone, good biocompatibility, excellent chemical stability and projectability. However, the highly hydrophobic surface of PEEK is biologically inert, which makes it difficult for cells and proteins to attach, and is accompanied by the development of infections that ultimately lead to failure of PEEK implants. In order to further enhance the potential of PEEK as an orthopedic implant, researchers have explored modification methods such as surface modification by physical and chemical means and the addition of bioactive substances to PEEK-based materials to enhance the mechanical properties, osteogenic activity and antimicrobial properties of PEEK. However, these current modification methods still have obvious shortcomings in terms of cost, maneuverability, stability and cytotoxicity, which still need to be explored by researchers. This paper reviews some of the modification methods that have been used to improve the performance of PEEK over the last three years in anticipation of the need for researchers to design PEEK orthopedic implants that better meet clinical needs.

A Biomimetic Fibrous Composite Scaffold with Nanotopography-Regulated Mineralization for Bone Defect Repair.

The effective regeneration of large bone defects via bone tissue engineering is challenging due to the difficulty in creating an osteogenic microenvironment. Inspired by the fibrillar architecture of the natural extracellular matrix, we developed a nanoscale bioengineering strategy to produce bone fibril-like composite scaffolds with enhanced osteogenic capability. To activate the surface for biofunctionalization, self-adaptive ridge-like nanolamellae were constructed on poly(ε-caprolactone) (PCL) electrospinning scaffolds via surface-directed epitaxial crystallization. This unique nanotopography with a markedly increased specific surface area offered abundant nucleation sites for Ca2+ recruitment, leading to a 5-fold greater deposition weight of hydroxyapatite than that of the pristine PCL scaffold under stimulated physiological conditions. Bone marrow mesenchymal stem cells (BMSCs) cultured on bone fibril-like scaffolds exhibited enhanced adhesion, proliferation, and osteogenic differentiation in vitro. In a rat calvarial defect model, the bone fibril-like scaffold significantly accelerated bone regeneration, as evidenced by micro-CT, histological histological and immunofluorescence staining. This work provides the way for recapitulating the osteogenic microenvironment in tissue-engineered scaffolds for bone repair.

Durable and Robust Antibacterial Polypropylene Hernia Mesh for Abdominal Wall Defect Repair.

Polypropylene (PP) mesh is commonly used in repairing abdominal wall hernia (AWH). However, the use of synthetic prosthesis comes with the risk of developing a prosthetic infection, resulting in delayed healing, secondary surgery, and potentially increased mortality. To address these issues, a facile surface functionalization strategy for PP mesh based on phytic acid (PA) and polyhexamethylene guanidine (PHMG) was constructed through a one-step co-deposition process, referred to as the PA/PHMG coating. The development of PA/PHMG coating is mainly attributed to the surface affinity of PA and the electrostatic interactions between PA and PHMG. The PA/PHMG coating could be completed within 4 h under mild conditions. The prepared PA/PHMG coatings on PP mesh surfaces exhibited desirable biocompatibility toward mammalian cells and excellent antibacterial properties against the notorious "superbug" methicillin-resistant Staphylococcus aureus (MRSA) and tetracycline-resistant Escherichia coli (TRE). The PA/PHMG-coated PP meshes showed killing ratios of over 99% against MRSA in an infected abdominal wall hernia repair model. Furthermore, histological and immunohistochemical analysis revealed a significantly attenuated degree of neutrophil infiltration in the PA/PHMG coating group, attributed to the decreased bacterial numbers alleviating the inflammatory response at the implant sites. Meanwhile, the pristine PP and PA/PHMG-coated meshes showed effective tissue repair, with the PA/PHMG coating group exhibiting enhanced angiogenesis compared with pristine PP meshes, suggesting superior tissue restoration. Additionally, PP meshes with the highest PHMG weight ratio (PA/PHMG(3)) exhibited excellent long-term robustness under phosphate-buffered saline (PBS) immersion with a killing ratio against MRSA still exceeding 95% after 60 days of PBS immersion. The present work provides a facile and promising approach for developing antibacterial implants.

Versatile Biomass‐Based Injectable Photothermal Hydrogel for Integrated Regenerative Wound Healing and Skin Bioelectronics

AbstractThe continuously growing utilization of wound healing materials and skin bioelectronics urges the development of flexible hydrogels for personal therapy and health management. Versatile conductive hydrogels prepared from natural biomass are ideal candidates as one of the promising solutions for chronic wound management. Here, the study proposes a kind of robust (strain: 1560.8%), adhesive, self‐healing, injectable, antibacterial (sterilization rate: 99%), near‐infrared (NIR) photothermal responsive, biocompatible, and conductive hydrogel (CPPFe@TA) composed of carboxymethyl cellulose and tannic acid/iron ion complex (TA@Fe3+), featuring rapid self‐assembly and tunable crosslinking time. TA@Fe3+ facilitated the self‐catalysis of the polymerization reaction, and the crosslinking time could be controlled by adjusting Fe3+ concentration. Under NIR irradiation, the hydrogel exhibited remarkable photothermal antibacterial performance. In the full‐thickness skin defect repair experiment on mice, the prepared hydrogel dressing significantly enhanced wound healing. After 14 days, the wound healing rate (95.49%) of CPPFe@TA3 hydrogel + NIR treatment greatly exceeded that of commercial dressings. Meanwhile, the hydrogels has good electrical conductivity and thermo‐responsiveness, making them promising for skin bioelectronics in physiological signal monitoring and rehabilitation exercise management. This work therefore offers a promising strategy for developing versatile biomass‐based hydrogels, which is expected to be applicable to integrated regenerative wound healing and skin bioelectronics.

Silicon-induced biofilm improves peripheral nerve defect in rats mediated by VEGF/VEGFR2/ERK

ABSTRACT Background: Injury of peripheral nerve capable of regeneration with much poorer prognosis affects people’s life quality. The recovery of nerve function after transplantation for peripheral nerve injury remain a worldwide problem. Silicon-induced biofilms as vascularized biological conduits can promote nerve regeneration by encapsulating autologous or allogeneic nerve graft. Objective: We proposed to explore the effect of silicon-induced biofilms on nerves regeneration and whether the VEGF/VEGFR2/ERK pathway was involved in the present study. Methods: Biofilms around the transplanted nerves in peripheral nerve injury rats were induced by silicon. Vascularization and proteins related to VEGF/VEGFR2/ERK were measured. Pathology and morphology of nerves were investigated after encapsulating the transplanted nerves by silicon-induced biofilms. Results: Our results indicated that the biofilms induced by silicon for 6 weeks showed the most intensive vascularization and the optimal effect on nerve regeneration. Moreover, silicon-induced biofilms for 4, 6 and 8 weeks could significantly secrete VEGF with the highest content at week 6 after induction. VEGFR2, VEGF, p-VEGFR2, ERK1, ERK2, p-ERK1 and p-ERK2 were expressed in the biofilms. p-VEGFR2, p-ERK1 and p-ERK2 expression were different at each time point and significantly increased at week 6 compared with that at week 4 or week 8 which was consistent with that 6 week of was the optimum time for biofilms induction to improve the nerve repair after peripheral nerve injury. Conclusion: Our results suggested that combination of silicon-induced autologous vascularized biofilm and autologous transplantation may promote the repair of rat sciatic nerve defect quickly through VEGF/VEGFR2/ERK pathway.

Repair of Adjacent Superior Helix and Posterior Auricle Defects.

Repair of Adjacent Superior Helix and Posterior Auricle Defects.

Outcomes and Complications of Sole Reconstruction Using Lateral Thoracic Free Tissue Transfer.

The complex structure of the sole of the foot makes the repair of extensive defects challenging. The present study, therefore, aimed to address a gap in current research by evaluating the potential of the lateral thoracic free flap, including perforator options and chimeric configurations, to be used as an advanced solution for comprehensive sole reconstruction. We retrospectively collected the following data from the charts of patients with sole defects, due to various causes, who underwent lateral thoracic free tissue transfers: patient demographics; etiologies; comorbidities; flap types and dimensions; pedicle length; operative time; follow-up period; complications; and management. The present study included 54 patients who underwent lateral thoracic free tissue transfer, citing infection, trauma, tumor, and posttraumatic sequelae as the major etiologies. We used the following techniques for the reconstruction of sole defects: thoracodorsal artery perforator free flap (83.3%); latissimus dorsi musculocutaneous free flap (1.9%); and various chimeric pattern flaps (14.8%). Free tissue transfer in the lateral thoracic region offers versatility for reconstruction, as well as low donor site morbidity. Complications observed in the present study included wound dehiscence (9.3%), partial necrosis (9.3%), and pressure ulcers (22.2%), although most patients healed favorably without flap loss. The lateral thoracic free flap is a viable option for the reconstruction of the sole of the foot and allows for the effective reconstruction of complex defects. It contains a sustainable skin paddle, and multiple components can be easily included as a chimeric type. Further studies should seek to identify ways to prevent pressure ulcers, which was the only known long-term complication in the present study.

Investigation of structure, morphology, and corrosion behavior of carboxylic acids/hydroxyapatite/chitosan coatings on Ti discs for implants

Titanium (Ti) and its alloys are widely used in bone defect repair owing to their advantages, including high strength, corrosion resistance, and biocompatibility. The formation of a stable oxide layer on Ti implants enhances the osseointegration process. Nevertheless, additional progress is required to improve the incorporation of these implants at the microscopic and nanoscopic levels to achieve a biocompatible interface. The main objective of this study was to enhance the morphology of hydroxyapatite and the corrosion resistance of Ti implants by applying hydroxyapatite/chitosan (HA/Cs) nanocomposite coatings embedded with carboxylic acids. The coatings were fabricated by electrodeposition, wherein various acid concentrations (acrylic and acetic acids) were employed as Cs electrolyte solvents to enhance the adhesion and bond strength with the titanium metal substrate. The microstructures of the HA/Cs coatings were analyzed using X-ray diffraction. The results demonstrated that the structure of HA was affected by the type of acid used and its concentration as the crystallinity increased with a high concentration of acrylic acid. Additionally, the morphology of HA/Cs was analyzed using a transmission electron microscope. The results showed that the morphology of HA/Cs changed from a hexagonal rod-like shape with acrylic acid samples into a needle-like shape in acetic acid samples. The corrosion behavior was investigated using electrochemical impedance spectroscopy (EIS) in a simulated body fluid (SBF) at 37±2ºC. The EIS results showed a high corrosion resistance with phase angles close to −80° and high impedance values of 80.5 kΩ cm2 with a high concentration of acrylic acid. These results indicated the formation of a highly adhesive and stable film on the implants in the test solution. In conclusion, based on this study and our previous work, the corrosion resistance, good biocompatibility, and biomineralization properties of the prepared HA/Cs-coated Ti recommend it as an alternative implant for clinical applications.

MiR-26b-5p/TET3 regulates the osteogenic differentiation of human bone mesenchymal stem cells and bone reconstruction in female rats with calvarial defects

MiR-26b-5p/TET3 regulates the osteogenic differentiation of human bone mesenchymal stem cells and bone reconstruction in female rats with calvarial defects

Study on liver tissue derived-extracellular vesicles regulating the osteogenic differentiation ability of mesenchymal stem cells and promoting the healing of jaw bone defects

Objective: To explore the biological process of liver tissue-derived extracellular vesicle (LT-EV) in promoting osteogenic differentiation of mesenchymal stem cells and healing of jaw defects to provide a feasible treatment method for the clinical treatment of jaw bone defects. Methods: Enzymatic hydrolysis and differential centrifugation were used to extract LT-EV, scanning electron microscopy, Western blotting, and nanoparticle tracking analyzers were used to identify and characterize LT-EV, and further to explore the biological functions of LT-EV through proteomics and Kyoto Encyclopedia of Genes and Genomes. Flow cytometry was used to detect LT-EV plasma concentration and to calculate the plasma half-life of LT-EV. Small animal in vivo imaging system was used to detect the biological distribution of LT-EV 24 hours after injection. Six C57BL/6 mice were divided into control group and LT-EV group (3 mice in each group) by simple random sampling method. All mice underwent jaw bone defect surgery and tail vein injection every 7 days (the control group was injected with phosphoric buffer saline, LT-EV group was injected with LT-EV), micro-CT was used to evaluate the degree of mouse jaw bone healing 28 days after surgery, HE staining was used to analyze the multi-organ biosafety of LT-EV, and immunofluorescence staining was used to detect the jaw bone expression of osteogenic marker proteins in the defect area. Human jaw bone mesenchymal stem cells (hJBMSC) induced by osteogenic differentiation were treated with LT-EV (obtained from orthognathic surgery patients provided by the Department of Traumatology and Orthognathic Surgery of School of Stomatology of The Fourth Military Medical University resected normal jaw bone fragments), and the difference in osteogenic differentiation ability between the hJBMSC group and the control group (phosphate buffer saline treatment) was compared, and the in vitro bone differentiation promoting effect of LT-EV was verified through alkaline phosphatase (ALP) staining and real-time fluorescence quantitative PCR. Results: The yield of LT-EV was high, and proteomics and Kyoto Encyclopedia of Genes and Genomes showed that LT-EV contained a series of proteins that regulated cell biological functions. LT-EV injected into the tail vein could reach the mouse jaw bone defect area and promote the regeneration and repair of the jaw bone defect [the bone volume fractions of the LT-EV group and the control group were (36.06±4.20)% and (18.58±5.61)%, respectively; t=4.32, P=0.013], and had good biosafety. LT-EV could promote osteogenic differentiation of hJBMSC in vitro. Compared to the control group, ALP staining and osteogenic gene expression levels were significantly enhanced after osteogenic differentiation of hJBMSC (P<0.05). Conclusions: LT-EV exhibits a high yield, ease of acquisition, high biological safety, and excellent bone-promoting effects. It holds promise as a novel cell-free therapy strategy for regenerating craniofacial bone defects.

Repair of a Complex Medial Canthal Defect

Repair of a Complex Medial Canthal Defect

Improving the UV transmittance of synthetic quartz through defect repair methods

Synthetic quartz materials with high ultraviolet transmittance are widely used in lenses and other optical devices. However, the relatively insufficient transmittance limits the application. In this paper, method of Defect Compensation is proposed to reduce the content of ODC, E'center and NBOHC and synthetic quartz glass with UV high transmittance was prepared successfully. The glass has high transmittance with internal transmittance of 99.9%@193nm, low stress birefringence with 0.9nm/cm @632.8nm and good optical homogeneity with 0.78ppm @ 632.8nm.

Mechanistic study on the role of 3D-Printed biomimetic coral bone scaffolds in bone defect repair

With the continuous innovation and development of 3D printing technology, 3D-printed biomimetic coral bone scaffolds have demonstrated significant potential in the field of bone defect repair. This paper aims to explore in-depth the mechanistic study of 3D-printed biomimetic coral bone scaffolds in bone defect repair, by systematically reviewing relevant literature and analyzing their potential mechanisms in promoting bone growth and improving the success rate of bone defect repair. Firstly, this paper introduces the fabrication process and material characteristics of 3D-printed biomimetic coral bone scaffolds. Secondly, the paper discusses the mechanisms of 3D-printed biomimetic coral bone scaffolds in terms of biocompatibility, biomechanical performance, as well as their roles in vascularization and bone formation. Finally, the paper outlines future research directions for 3D-printed biomimetic coral bone scaffolds, including further optimization of material properties, improvement of printing precision, and expansion of clinical applications.