Ceramic Scaffolds Research Articles

Exploring the mechanical and biological properties of a resin-ceramic composite with biomimetic nacre structure containing zinc used for prosthodontics

Enhancement of the mechanical and biological properties of dental restoration materials is of significant importance. Drawing inspiration from the architecture and mechanical properties of natural nacre, we employed a low-cost accumulative rolling process to develop resin-ceramic composites with suitable hardness and high toughness. Plate-like aluminum oxide powder with diameters of 5–10 μm and nano-zinc oxide (ZnO) with antibacterial properties were mixed as the ceramic phase of the composite. Aluminum oxide ceramic plates were stacked using an accumulative rolling process to achieve a consistent orientation, followed by sintering to obtain porous ceramic scaffolds. The ceramic scaffolds were subsequently immersed in methyl methacrylate resin to complete the fabrication of the biomimetic composites. The mechanical and biological properties of the composites were comprehensively tested. The composites had a suitable hardness (1.09–1.63 GPa), excellent flexural strength (156.7–167.8 MPa), and fracture toughness (KIC = 2.66–3.59 MPa m1/2). Biomimetic composites are expected to mitigate the wear of natural teeth without developing fractures or deformations, while also exhibiting excellent cytocompatibility and antibacterial activity. This study investigated the factors influencing crack propagation in fracture tests and provided insights into enhancing the toughness of dental restorative materials. The biomimetic resin-ceramic composites containing Zn developed in this study have the potential to be used as functional dental restoration materials.

Biphasic Calcium Phosphate Ceramic Scaffold Composed of Zinc Doped β-Tricalcium Phosphate and Silicon Doped Hydroxyapatite for Bone Tissue Engineering.

The rapid repair of bone defects remains a significant clinical challenge to this day. To address this issue, a 3D-printed biphasic calcium phosphate (BCP) scaffold consisting of 40 wt % hydroxyapatite (HA) and 60 wt % β-tricalcium phosphate (β-TCP) was created. Silicon and zinc were incorporated into HA and β-TCP, respectively, to enhance the angiogenic and osteogenic properties of the BCP scaffold. The physicochemical properties, in vitro cell responses, and bone defect repair efficacy of the modified BCP scaffold were comprehensively investigated. Results showed that the fabricated scaffold possessed a 3D interconnected pore structure. Zinc doping enhanced the sintering of the BCP scaffold, increased its density and strength, but decreased its degradation rate. Conversely, silicon doping had the opposite effect. The modified scaffold was capable of a gradual release of zinc/silicon ions, which promoted the proliferation and differentiation of cells. Specifically, the scaffold doped with zinc significantly promoted the osteogenic differentiation of stem cells. Moreover, co-doping with silicon and zinc synergistically promoted in vitro angiogenesis, with BCP-3 (doped with 2.5 mol % zinc and 4 mol % silicon) exhibiting the best pro-angiogenic activity. BCP-3 significantly induced regeneration of blood vessels and bone tissue in vivo, indicating its potential to accelerate the process of bone defect repair.

All-Natural Ceramic Whitlockite/Wollastonite Fiber Composite Bone Scaffolds: DLP Additive Manufacturing, Microstructure, and Performance

In this study, we introduced a novel approach by using natural calcium phosphate-based ceramic whitlockite as the matrix, natural silicon-based ceramic wollastonite fiber as the secondary phase, and desktop-level DLP 3D printing as the fabrication method to develop an all-natural ceramic porous bone scaffold with excellent mechanical, degradable, biomineralization, and cell responses. The results demonstrated that, at a solid loading of 75 wt% and a sintering temperature of 1000°C, the compressive strength of the whitlockite porous scaffold reached 20.0 MPa. With the incorporation of wollastonite fiber, the compressive strength of the composite ceramic scaffold further increased to 31.0 MPa, achieving a top-tier level for desktop-level DLP-printed porous ceramic bone scaffolds. This mechanical enhancement effect was mainly attributed to the grain refinement effect of WF on whitlockite and the fiber reinforcement effect of WF. Additionally, the degradation rate of the composite ceramic scaffold increased with higher WF content, attributed to the rapid degradation rate of WF and the microstructural changes in the whitlockite matrix induced by WF doping. Furthermore, the biomineralization capability and cellular response of the composite ceramic scaffold were enhanced with WF doping, due to the improved degradation ability promoting the release of calcium, phosphate, and silicon ions. This study further validates the applicability of desktop-level DLP for fabricating ceramic bone scaffolds and provides evidence of the potential of all-natural ceramic whitlockite/WF as bone scaffold materials.

3D printing of porous ceramic scaffold based halloysite clay for efficient seawater desalination

3D printing of porous ceramic scaffold based halloysite clay for efficient seawater desalination

Study on performance regulation of electro-mechanical properties 3D printed BaTiO3/HA porous structure composite ceramic

BaTiO3/Ca10(PO4)6(OH)2 composite ceramic is an outstanding representative of piezoelectric biomaterials, with excellent biocompatibility and piezoelectric effect, and has potential applications in the field of bone tissue repair. In this work, vat photopolymerization 3D printing technology was used to fabricate triply periodic minimal surface structure BaTiO3/Ca10(PO4)6(OH)2 composite ceramic bone tissue scaffolds with different pore sizes and porosity, and their mechanical and electrical properties were studied. First, the ceramic slurry configuration process was optimized to obtain a ceramic slurry with high solid content (45 vol%) and excellent rheological properties. Then the effect of sintering temperature on microstructure, relative density, mechanical properties, and electrical properties is discussed. The results show that when sintering at 1300 °C, the BaTiO3/Ca10(PO4)6(OH)2 composite ceramic has the highest relative density (99.18 %), the highest compressive strength (44 MPa), large relative dielectric constant (379–389), and low dielectric loss. The polarization electric field strength of the BaTiO3/Ca10(PO4)6(OH)2 composite ceramic was set to 15 kV/cm through the test of the hysteresis loop. Finally, based on multi-physics coupled finite element simulation, the effects of different porosity and different pore sizes on stress distribution and piezoelectric potential were analyzed, and the relationship between them was explored through experiments. The results show that as the porosity increases and the pore size decreases, the mechanical properties of the scaffold decrease significantly, and its compressive strength ranges between 1.67 and 4.26 MPa; as the porosity increases and the pore size increases, the piezoelectric coefficient (d33) of the scaffold showed a decreasing trend, and its d33 ranged between 2 and 9 pC/N. The mechanical and electrical properties of the scaffold meet the performance requirements of cancellous bone. In summary, this work provides a strategy for the application of customized BaTiO3/Ca10(PO4)6(OH)2 composite ceramic scaffolds in new-generation orthopedic implants.

Ceramic/metal composites fabricated via 3D printing and ultrasonic-assisted infiltration for high specific strength and energy absorption

To address the strength-toughness dilemma, ceramic/metal interpenetrating phase composites (IPCs), fabricated through metal infiltration into ceramic perform, have been investigated. However, infiltrating metal into porous ceramic scaffold with high volume fraction remains a significant challenge. Herein, we propose a novel method to fabricate highly dense Al2O3/AlSi10Mg (Al) interpenetrating phase composites through ultrasonic-assisted pressureless infiltration into 3D printed ceramic scaffolds. Experimental results indicate that the as-fabricated Al2O3/Al IPCs exhibit excellent quasi-static and dynamic mechanical properties. Specifically, the materials can achieve high specific compressive strengths of 148.6 ± 5.2 MPa/(g/cm3) under quasi-static compression and 228.6 ± 4.5 MPa/(g/cm3) under dynamic compression while also exhibiting high specific energy absorption of 33.6 ± 0.9 J/g under quasi-static compression and 37.7 ± 1.1 J/g under dynamic compression. The specific compressive strength and specific energy absorption of the as-fabricated Al2O3/Al IPCs outperform those of the literature-reported ceramic/metal IPCs. This work provides an innovative approach to fabricate strong and tough ceramic composites.

Fabrication, physicochemical properties, and cytocompatibility of 3D-printed Sr2MgSi2O7 bioceramic scaffolds calcined at different temperature for bone repair

3D-printed bioactive ceramic scaffolds hold significant promise for addressing critical-size bone defects, owing to their biodegradable and osteogenic properties. Numerous 3D-printed silicate-based (e.g., Sr2MgSi2O7) ceramic scaffolds have been developed, but the rapid degradation and insufficient mechanical properties of which impede their application efficacy. Despite recognizing the pivotal role of calcination temperature in shaping the physicochemical and biological attributes of 3D-printed scaffolds, its specific influence on Sr2MgSi2O7 bioceramics remains ambiguous. This study elucidated the fabrication, physicochemical properties, and cytocompatibility of 3D-printed Sr2MgSi2O7 ceramic scaffolds calcined at different temperatures. The findings revealed a significant enhancement in compressive strength (up to 19.9 MPa) and a decrease in degradation rate with increasing calcination temperature. Compared to conventional tricalcium phosphate scaffolds, Sr2MgSi2O7 scaffold demonstrated superior osteogenic potential, particularly when calcined at 1250°C. With commendable mechanical strength and remarkable osteogenic capabilities, the Sr2MgSi2O7 scaffold emerges a promising avenue for repairing critical-size bone defects.

3D printing of flexible piezoelectric composite with integrated sensing and actuation applications

3D printing of flexible piezoelectric composites (3D-FPCs) is increasingly attracting the attention due to its unique advantage for customized smart applications. However, current research mainly focuses on the 0–3 piezoelectric composites, in which the piezoelectric ceramics are embedded in polymer matrix in the form of particles. The poor connectivity between particles much reduces the conduction of strain and charge in the composites, seriously limiting its application in actuation. In this work, a continuous lead zirconate titanate (PZT) double-layer ceramic scaffold was prepared by 3D printing and assembled with epoxy resin and interdigital electrodes together to manufacture a multifunctional device. The 3D-FPCs exhibit a free strain of 1830 ​ppm in actuating and are able to actuate a stainless-steel cantilever beam to produce a tip displacement of 5.71 ​mm. Additionally, the devices exhibit a sensitivity of 26.81V/g in sensing applications. Furthermore, 3D-FPCs are demonstrated as actuators for mobile small robots and wearable sensors for sensing joint activities.

Improving mechanical strength and osteo-stimulative capacity of 3D-printed magnesium phosphate ceramic scaffolds by magnesium silicate additives

Magnesium phosphate ceramics are short of osteostimulation capacity to effectively repair the bone defects. Herein, magnesium silicate (MgSi) was utilized as an additive to modify the 3D-printed magnesium phosphate (MgP) ceramic scaffolds. The results presented that the addition of MgSi was conducive to enhancement of compressive strength of the MgP/MgSi ceramic composite scaffolds, and the scaffolds incorporating 20 wt% MgSi had the highest value. The degradation of MgP/MgSi scaffolds resulted in a decrease of mechanical strength and the continuous release of magnesium and silicon ions. In comparison with MgP scaffolds, the MgP/MgSi scaffolds promoted the growth and osteogenic gene expression of bone marrow mesenchymal stem cells. Collectively, the 3D-printed MgP/MgSi scaffolds with high mechanical strength and osteo-stimulation effects are potential biomaterials for the effective restoration of bone defects.

Piezoelectric properties and biocompatibility of barium titanate prepared via digital light processing

Barium titanate (BT) is widely studied in bone repair engineering due to its high dielectric constant, excellent ferroelectric properties, and non-toxic nature. However, one of the research focuses on the preparation of high-precision BT ceramics and enhances their limited mineralization bioactivity. BT is difficult to use for high-precision ceramic molding using Digital Light Processing (DLP) due to its high refractive index and strong ultraviolet absorption. In this manuscript, BT was doped with calcium silicate (CS) which has a refractive index close to photosensitive resin. The printing parameters of the composite ceramic scaffolds were determined to obtain a balance between printing efficiency and accuracy. Experimental results have demonstrated that within a CS doping ratio of up to 20 wt%, the scaffolds simultaneously meet the piezoelectric coefficient and mechanical properties of natural bone. Furthermore, mineralization and cell experiments have shown that the composite scaffold exhibits improved degradation rate, cell activity, and osteoinductivity. Subsequently, bone scaffolds with a doping ratio of 20 wt% were selected, which meet the requirements of natural bone and exhibit significantly enhanced biological activity. Research findings revealed that ceramic scaffolds after piezoelectric stimulation are more conducive to cell proliferation and growth compared to before stimulation.

Microstructure and mechanical properties of freeze-casted in-situ ABOw@Al2O3/AZ91 composites

In this work, the A18B4O33w (ABOw) was in-situ generated on the surface of Al2O3 through the reaction of B2O3 and Al2O3, resulting in the thorn structure. Then, the ABOw@Al2O3/AZ91 composites were fabricated through a combination of freeze casting and pressure casting. The influence of the initial content of B2O3 on the microstructure and mechanical properties of ABOw@Al2O3/AZ91 composites was investigated. The results show that the lamellar structure of ABOw@Al2O3/AZ91 composites were weakened, which gradually changed to dendritic structure with the increasing B2O3 content. The in-situ formation of ABOw on the surface of Al2O3 was favorable to improve the compressive strength of both ABOw@Al2O3 ceramic scaffold and ABOw@Al2O3/AZ91 composites, while also reducing the anisotropy of the composites. Furthermore, the in-situ generated ABOw within the ceramic layer could effectively relieve stress concentration and delay crack initiation and propagation, which led to the enhancement of the load-bearing capacity of ABOw@Al2O3/AZ91 composites. The ABOw@Al2O3/AZ91 composite exhibited the outstanding mechanical properties with the compressive strength of ∼685 MPa, when the B2O3's content is 5 wt%.

In-situ grown columnar mullite reinforced SiC porous ceramic membrane support with excellent mechanical performance and corrosion resistance: Using TiO2 as the key to form columnar mullite

In this study, in-situ growth of columnar mullite reinforced silicon carbide porous membrane supports were prepared, and the addition of TiO2 helped to reduce the sintering temperature for the anisotropic growth of necked columnar mullite crystals. The synthesis of in situ columnar mullite makes reasonable use of the oxidized silica of silicon carbide, and in turn reduces the loss of the silicon carbide porous membrane support under strong corrosive conditions. The material showed a flexural strength of up to 72.95 MPa, and a water flux of 31612.83 L·m−2·h−1·bar−1 when sintered for 2 h in an air environment at 1250 °C. The flexural strength after corrosion in 20 vol% H2SO4 and 1 wt% NaOH solution (90 °C) exceeded 93 %. This shows that this porous silicon carbide ceramic membrane scaffold has potential applications in the field of water treatment under harsh environments.

Rapid prototyping of perfusion cell culture devices for three-dimensional imaging of mesenchymal stem cell deposition and proliferation

Perfusion of porous scaffolds transports cells to the surface to yield cellular constructs for 3D models of disease and for tissue engineering applications. While ceramic scaffolds mimic the structure and composition of trabecular bone, their opacity and tortuous pores limit the penetration of light into the interior. Scaffolds that are both perfusable and amenable to fluorescence microscopy are therefore needed to visualize the spatiotemporal dynamics of cells in the bone microenvironment. In this study, a hybrid injection molding approach was designed to enable rapid prototyping of collector arrays with variable configurations that are amenable to longitudinal imaging of attached human mesenchymal stem cells (hMSCs) using fluorescence microscopy. Cylindrical collectors were arranged in an array that is permeable to perfusion in the xy-plane and to light in the z-direction for imaging from below. The effects of the collector radius, number, and spacing on the collection efficiency of perfused hMSCs was simulated using computational fluid dynamics (CFD) and measured experimentally using fluorescence microscopy. The effect of collector diameter on simulated and experimental cell collection efficiencies followed a trend similar to that predicted by interception theory corrected for intermolecular and hydrodynamic forces for the arrays with constant collector spacing. In contrast, arrays designed with constant collector number yielded collection efficiencies that poorly fit the trend with collector radius predicted by interception theory. CFD simulations of collection efficiency agreed with experimental measurements within a factor of two. These findings highlight the utility of CFD simulations and hybrid injection molding for rapid prototyping of collector arrays to optimize the longitudinal imaging of cells without the need for expensive and time-consuming tooling.

The electrical properties and in vitro osteogenic properties of 3D‐printed MgO@BT/HA piezoelectric ceramic disk

AbstractThe repair of bone defects from various causes remains a significant challenge in clinical settings. Piezoelectric materials have been demonstrated to promote osteogenic differentiation, among which barium titanate (BT) has been widely reported. Magnesium oxide (MgO) dopants not only enhance the piezoelectric properties but also stimulate the osteogenic and angiogenic properties in stem cells. In this study, a MgO‐modified BT/hydroxyapatite (MgO@BT/HA) piezoelectric ceramic scaffold was constructed using three‐dimensional (3D)‐printed technology. The results indicated that the addition of MgO improved the electrical properties of BT (d33 = 68.26 pC/N), and facilitated an increase in the proportion of HA (30%) while maintaining the piezoelectric coefficient (d33 = 2.04 pC/N) of the ceramic system. Furthermore, under the induction of low‐intensity pulsed ultrasound (LIPUS) stimulation, in vitro biosafety experiments confirmed that MgO@BT/HA exhibits excellent biosafety and promotes the osteogenic differentiation of dental pulp stem cells (DPSCs).

Fabrication and Evaluation of PCL/PLGA/β-TCP Spiral-Structured Scaffolds for Bone Tissue Engineering.

Natural bone is a complex material that has been carefully designed. To prepare a successful bone substitute, two challenging conditions need to be met: biocompatible and bioactive materials for cell proliferation and differentiation, and appropriate mechanical stability after implantation. Therefore, a hybrid Poly ε-caprolactone/Poly(lactic-co-glycolide)/β-tricalcium phosphate (PCL/PLGA/β-TCP) scaffold has been introduced as a suitable composition that satisfies the above two conditions. The blended PCL and PLGA can improve the scaffold's mechanical properties and biocompatibility compared to single PCL or PLGA scaffolds. In addition, the incorporated β-TCP increases the mechanical strength and osteogenic potential of PCL/PLGA scaffolds, while the polymer improves the mechanical stability of ceramic scaffolds. The PCL/PLGA/β-TCP scaffold is designed using spiral structures to provide a much better transport system through the gaps between spiral walls than conventional cylindrical scaffolds. Human fetal osteoblasts (hFOBs) were cultured on spiral PCL/PLGA/β-TCP (PPBS), cylindrical PCL/PLGA/β-TCP (PPBC), and cylindrical PCL scaffolds for a total of 28 days. The cell proliferation, viability, and osteogenic differentiation capabilities were analyzed. Compared with PCL and PPBC scaffolds, the PPBS scaffold exhibits great biocompatibility and potential to stimulate cell proliferation and differentiation and, therefore, can serve as a bone substitute for bone tissue regeneration.

Ti3C2Tx MXene-Decorated 3D-Printed Ceramic Scaffolds for Enhancing Osteogenesis by Spatiotemporally Orchestrating Inflammatory and Bone Repair Responses.

Inflammatory responses play a central role in coordinating biomaterial-mediated tissue regeneration. However, precise modulation of dynamic variations in microenvironmental inflammation post-implantation remains challenging. In this study, the traditional β-tricalcium phosphate-based scaffold is remodeled via ultrathin MXene-Ti3C2 decoration and Zn2+/Sr2+ ion-substitution, endowing the scaffold with excellent reactive oxygen species-scavenging ability, near-infrared responsivity, and enhanced mechanical properties. The induction of mild hyperthermia around the implant via periodic near-infrared irradiation facilitates spatiotemporal regulation of inflammatory cytokines secreted by a spectrum of macrophage phenotypes. The process initially amplifies the pro-inflammatory response, then accelerates M1-to-M2 macrophage polarization transition, yielding a satisfactory pattern of osteo-immunomodulation during the natural bone healing process. Later, sustained release of Zn2+/Sr2+ ions with gradual degradation of the 3D scaffold maintains the favorable reparative M2-dominated immunological microenvironment that supports new bone mineralization. Precise temporal immunoregulation of the bone healing process by the intelligent 3D scaffold enhances bone regeneration in a rat cranial defect model. This strategy paves the way for the application of β-tricalcium phosphate-based materials to guide the dynamic inflammatory and bone tissue responses toward a favorable outcome, making clinical treatment more predictable and durable. The findings also demonstrate that near-infrared irradiation-derived mild hyperthermia is a promising method of immunomodulation.

Production of ceramic alumina scaffolds via ceramic stereolithography with potential application in bone tissue regeneration

Scaffolds are devices that mimic the characteristics of the extracellular matrix; they are highly porous, with well-distributed and interconnected pores. Tissue engineering proposes scaffolds as an alternative treatment for different diseases and injuries affecting bone tissue. Triply periodic minimal surfaces (TPMS) are geometric structures whose characteristics fit well with the scaffold’s requirements. Ceramic stereolithography enables the production of these complex geometries with high precision using ceramic materials. Alumina (Al2O3) is a well-known ceramic material appreciated for its chemical and mechanical stability properties. The biomedical use of alumina as an alternative to replace metallic parts in bone components has been increasing. In this work, a suspension of alumina particles in a photopolymerizable resin is developed in order to be implemented in the printing of ceramic scaffolds with TPMS-type geometries by ceramic stereolithography for potential biomedical applications. The resin used was characterized in a different work by TGA and FTIR (Duque et al., 2023) and is acrylic in nature, also the alumina particles were characterized by DTP and XRD, these are micrometer sized and a showed an α-alumina phase with a high degree of crystallinity. The rheological behavior of the suspension was studied with ceramic load percentages of 35, 40, and 50 vol% in order to choose the most favorable conditions for piece printing. The three suspensions presented low viscosities, being the 50 vol% sample the one that presented the highest viscosity, with an average value of 0.77 Pa s. These viscosities were suitable for the ceramic stereolithography printing process. The 50 vol% suspension was characterized by TGA and DSC and did not show any difference compared to the resin without particles. Scaffolds with TPMS Gyroid and Schwartz P geometry were obtained by ceramic stereolithography and characterized morphologically and mechanically before and after sintering. The thermal treatment was successful. The polymer-ceramic scaffolds before sintering exhibited better compression resistance than the sintered ones. Fully ceramic scaffolds with gyroid geometry showed compressive strength values of 0.4 MPa, which is comparable to human trabecular bone. The best compression resistance was for the samples with the gyroid geometry. Since the 50 vol% sintered scaffolds with gyroid geometry showed better mechanical results, they were impregnated with propolis extracts from the Arauca region of Colombia in order to evaluate their antimicrobial activity against the standard strains Staphylococcus aureus (ATCC 29212) and Escherichia coli (ATCC 25922). The evaluated scaffolds exhibited better antibacterial activity against the S. aureus strain. After sintering, the 50Al scaffolds were submitted to a degradation test in phosphate-buffered saline (PBS) to assess the chemical stability of the alumina. The results indicated that the samples maintained their initial weight throughout the testing period, with measurements taken on days 1, 5, 8, and 12 showing no significant changes in weight loss percentage. This stability suggests that the alumina scaffolds possess robust chemical resistance under the tested conditions.

Strong and tough β-TCP/PCL composite scaffolds with gradient structure for bone tissue engineering: Development and evaluation

Bioactive ceramic bone scaffolds are limited by their brittleness. To address this limitation, we developed a new method for preparing β-tricalcium phosphate (β-TCP)/polycaprolactone (PCL) porous composite scaffolds with a gradient structure using digital light processing technology and an impregnation process. The composite scaffolds exhibited compressive strength comparable to that of pure β-TCP scaffolds but with substantially higher toughness and reliability, especially during in vitro degradation. Owing to the gradient structure, the composite scaffolds could gradually shift from high strength and stiffness to moderate strength and low stiffness, which is beneficial for bone healing and remodeling. In femoral condyle defects without mechanical stimulation, the β-TCP/PCL composite scaffolds exhibited slightly lower cellular compatibility and osteoinductive ability than those of the pure β-TCP scaffolds. However, in radial defects, composite scaffolds demonstrated a better mechanical response and bone growth capacity. The composite scaffolds maintained their structural integrity after 2–4 months, whereas the β-TCP scaffolds fractured within 2 months. This study provides a novel methodology for the development of effective scaffold fabrication strategies for load-bearing or large segmental defects with complex stress applications for use in bone healing and remodeling.

The Electrical Properties and In Vitro Osteogenic Properties of 3D-Printed Fe@BT/HA Piezoelectric Ceramic Scaffold

The Electrical Properties and In Vitro Osteogenic Properties of 3D-Printed Fe@BT/HA Piezoelectric Ceramic Scaffold

Enhancing mechanical integrity of vat photopolymerization 3D printed hydroxyapatite scaffolds through overcoming peeling defects

In ceramic vat photopolymerization (VPP) fabrication, directly peeling originally designed scaffolds from the platform is efficient but often introduces defects, compromising the mechanical integrity of hydroxyapatite (HAp) scaffold. The peeling process involves the resistance of the HAp green scaffolds to peeling forces, which is influenced by its modulus and toughness. In this study, the peeling behavior of cubic-pore HAp (CP-HAp) green scaffolds with varying levels of modulus and toughness was investigated. The characterization results show that the HDDA CP-HAp scaffolds with relatively high levels of modulus and toughness could effectively resist the peeling forces and inhibit the occurrence of peeling defects. Stress concentration and inadequate toughness in the HEMA CP-HAp scaffolds lead to the formation of peeling defects. The CTFA and PHEA CP-HAp scaffolds with low modulus exhibit both peeling cracks and numerous pores. The cracks result from stress concentration, while the pores are caused by the coiled and loose molecular chain structure occupying space. Understanding the mechanism of peeling defect initiation in HAp porous scaffolds contributes to improving resistance to such defects and efficiently fabricating high-performance ceramic scaffolds using VPP.