Bioceramic Implants Research Articles

Enhanced Antibacterial Efficacy of Bioceramic Implants Functionalized with Ciprofloxacin: An In Silico and In Vitro Study.

This study explores the antibacterial efficacy and cytotoxicity of ciprofloxacin-functionalized bioceramic implants. We synthesized hydroxyapatite-ciprofloxacin (HACPXCS) composites and applied them to titanium substrates (Ti-HA-CPX), evaluating their performance in vitro against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922). Antibacterial activity was assessed using the Kirby-Bauer disc diffusion method, while cytotoxicity was tested using mesenchymal stem cells. The results demonstrated that Ti-HA-CPX exhibited superior antibacterial activity, with inhibition zones of 33.5 mm (MIC 0.5 µg/mL) for Staphylococcus aureus (ATCC 25923) and 27.5 mm (MIC 0.25 µg/mL) for Escherichia coli (ATCC 25922). However, Ti-HA-CPX showed moderate cytotoxicity (80% cell viability). HACPXCS composites, whether chemically synthesized or mechanically mixed (HACPXMM), also displayed significant antibacterial activity, but with cytotoxicity ranging from low to moderate levels. Molecular docking studies confirmed strong binding affinities between ciprofloxacin and bacterial proteins, correlating with enhanced antibacterial efficacy. These findings suggest that Ti-HA-CPX composites offer a promising approach for single-stage surgical interventions in treating chronic osteomyelitis and infected fractures, balancing antibacterial effectiveness with manageable cytotoxicity.

Evaluation of the elemental composition and radiological density of bone tissue when replacing a metaphyseal defect with bioceramic phosphate-silicate granules (experimental study)

Background: It is known that bioceramic implants containing various calcium or silicon compounds in isolation demonstrate osteoconductive effect in the replacement of post-traumatic bone defects. The combined use of these elements in single material should potentiate the organotypic filling of the bone cavity by creating favorable ion microenvironment and staged biodegradation. AIM: To identify the correlation of radiological indicators of the density of newly formed bone tissue and content of micro- and macronutrients in a bone defect when it is replaced by bioceramics with various mass ratio of calcium phosphate and silicate. MATERIALS AND METHODS: The study was performed on male rabbits of the “white giant” breed, which, after receiving a standardized delimited metaphysical bone defect, implants with variable ratio of calcium phosphate and calcium silicate (in proportions of 40/60, 50/50 and 60/40 wt. %) were used to replace it. The results were evaluated using multispiral computed tomography and scanning electron microscopy energy dispersive analysis with detection by the method of correlation analysis of possible connections between the obtained data. RESULTS: Quantitative indicators of calcium and phosphorus content in bone regenerate in all groups increased mainly in the period from 30 to 60 days, and silicon content, reaching maximum amounts by the 30th day of the experiment, subsequently decreased monotonously, which showed participation of this element in the starting regenerative processes, and its decrease served as a marker of organotypic restructuring. In the elemental analysis of newly formed bone tissue during implantation of bioceramics containing phosphate and calcium silicate in the proportion of 60/40 wt. %. The highest amounts of calcium, phosphorus and silicon and the highest density of newly formed bone tissue were noted, which had direct correlation, and this pattern was observed both in the early stages (30 days) and throughout the experimental study. CONCLUSION: Analyzing the data obtained, it can be concluded that it is advisable to study the features of the course of reparative osteogenesis depending on the ionic environment, as well as the high potential of using synthetic bioceramics in general and the prospects of using implants on the basis of phosphate-silicate composites for bone defects replacement.

Reconstruction of Craniomaxillofacial Bone Defects with 3D-Printed Bioceramic Implants: Scoping Review and Clinical Case Series.

Reconstruction of craniomaxillofacial bone defects using 3D-printed hydroxyapatite (HA) bioceramic patient-specific implants (PSIs) is a new technique with great potential. This study aimed to investigate the advantages, disadvantages, and clinical outcomes of these implants in craniomaxillofacial surgeries. The PubMed and Embase databases were searched for patients with craniomaxillofacial bone defects treated with bioceramic PSIs. Clinical outcomes such as biocompatibility, biomechanical properties, and aesthetics were evaluated and compared to those of commonly used titanium or poly-ether-ether-ketone (PEEK) implants and autologous bone grafts. Two clinical cases are presented to illustrate the surgical procedure and clinical outcomes of HA bioceramic PSIs. Literature review showed better a biocompatibility of HA PSIs than titanium and PEEK. The initial biomechanical properties were inferior to those of autologous bone grafts, PEEK, and titanium but improved when integrated. Satisfactory aesthetic results were found in our two clinical cases with good stability and absence of bone resorption or infection. Radiological signs of osteogenesis were observed in the two clinical cases six months postoperatively. HA bioceramic PSIs have excellent biocompatible properties and imitate natural bone biomechanically and radiologically. They are a well-suited alternative for conventional biomaterials in the reconstruction of load-sharing bone defects in the craniomaxillofacial region.

Unraveling the influence of channel size and shape in 3D printed ceramic scaffolds on osteogenesis

Bone has the capacity to regenerate itself for relatively small defects; however, this regenerative capacity is diminished in critical-size bone defects. The development of synthetic materials has risen as a distinct strategy to address this challenge. Effective synthetic materials to have emerged in recent years are bioceramic implants, which are biocompatible and highly bioactive. Yet nothing suitable for the repair of large bone defects has made the transition from laboratory to clinic. The clinical success of bioceramics has been shown to depend not only on the scaffold's intrinsic material properties but also on its internal porous geometry. This study aimed to systematically explore the implications of varying channel size, shape, and curvature in tissue scaffolds on in vivo bone regeneration outcomes. 3D printed bioceramic scaffolds with varying channel sizes (0.3 mm to 1.5 mm), shapes (circular vs rectangular), and curvatures (concave vs convex) were implanted in rabbit femoral defects for 8 weeks, followed by histological evaluation. We demonstrated that circular channel sizes of around 0.9 mm diameter significantly enhanced bone formation, compared to channel with diameters of 0.3 mm and 1.5 mm. Interestingly, varying channel shapes (rectangular vs circular) had no significant effect on the volume of newly formed bone. Furthermore, the present study systematically demonstrated the beneficial effect of concave surfaces on bone tissue growth in vivo, reinforcing previous in silico and in vitro findings. This study demonstrates that optimizing architectural configurations within ceramic scaffolds is crucial in enhancing bone regeneration outcomes. Statement of significanceDespite the explosion of work on developing synthetic scaffolds to repair bone defects, the amount of new bone formed by scaffolds in vivo remains suboptimal. Recent studies have illuminated the pivotal role of scaffolds’ internal architecture in osteogenesis. However, these investigations have mostly remained confined to in silico and in vitro experiments. Among the in vivo studies conducted, there has been a lack of systematic analysis of individual architectural features. Herein, we utilized bioceramic 3D printing to conduct a systematic exploration of the effects of channel size, shape, and curvature on bone formation in vivo. Our results demonstrate the significant influence of channel size and curvature on in vivo outcomes. These findings provide invaluable insights into the design of more effective bone scaffolds.

Three-Dimensional Printing Methods for Bioceramic-Based Scaffold Fabrication for Craniomaxillofacial Bone Tissue Engineering.

Three-dimensional printing (3DP) technology has revolutionized the field of the use of bioceramics for maxillofacial and periodontal applications, offering unprecedented control over the shape, size, and structure of bioceramic implants. In addition, bioceramics have become attractive materials for these applications due to their biocompatibility, biostability, and favorable mechanical properties. However, despite their advantages, bioceramic implants are still associated with inferior biological performance issues after implantation, such as slow osseointegration, inadequate tissue response, and an increased risk of implant failure. To address these challenges, researchers have been developing strategies to improve the biological performance of 3D-printed bioceramic implants. The purpose of this review is to provide an overview of 3DP techniques and strategies for bioceramic materials designed for bone regeneration. The review also addresses the use and incorporation of active biomolecules in 3D-printed bioceramic constructs to stimulate bone regeneration. By controlling the surface roughness and chemical composition of the implant, the construct can be tailored to promote osseointegration and reduce the risk of adverse tissue reactions. Additionally, growth factors, such as bone morphogenic proteins (rhBMP-2) and pharmacologic agent (dipyridamole), can be incorporated to promote the growth of new bone tissue. Incorporating porosity into bioceramic constructs can improve bone tissue formation and the overall biological response of the implant. As such, employing surface modification, combining with other materials, and incorporating the 3DP workflow can lead to better patient healing outcomes.

Dual-core-component multiphasic bioceramic granules with selective-area porous structures facilitating bone tissue regeneration and repair.

Ca-phosphate/-silicate ceramic granules have been widely studied because their biodegradable fillers can enhance bone defect repair accompanied with bioactive ion release and material degradation; however, it is a challenge to endow bioceramic composites with time-dependent ion release and highly efficient osteogenesis in vivo. Herein, we prepared dual-core-type bioceramic granules with varying chemical compositions beneficial for controlling ion release and stimulating osteogenic capability. Core-shell-structured bioceramic granules (P8-Sr4@Zn3, P8-Sr4@TCP, and P8-Sr4@HAR) composed of 8% P- and 4% Sr-substituting wollastonite (P8, Sr4) dual core components and different shell components, such as 3% Zn-substituting wollastonite (Zn3), β-tricalcium phosphate (β-TCP), and hardystonite (HAR), were prepared by cutting extruded core-shell fibers through dual-core ternary nozzles, followed by high-temperature sintering post-treatment. The experimental results showed that nonstoichiometric wollastonite core components contributed to more biologically active ion release in Tris buffer in vitro, and the sparingly dissolvable shell component readily maintained the granule morphology in vivo; thus, such bioceramic implants can adjust new bone growth and material degradation over time. In particular, bioceramic granules encapsulated by the TCP shell exhibited the most appreciable osteogenic capacity and expected biodegradation, which was mostly favorable for bone repair in critical bone defects. It is reasonable to consider that this new multiphasic bioceramic granule design is versatile for developing next-generation implants for various bone damage repairs.

High-resolution vat-photopolymerization of personalized bioceramic implants: new advances, regulatory hurdles, and key recommendations

ABSTRACT Bioceramics are in high demand due to their biocompatibility and bone-regenerative properties, representing a multibillion-dollar industry with orthopaedic and dental implant applications. However, traditional manufacturing methods have limitations in producing complex geometries tailored to match patient-specific bone defects. Vat-photopolymerization 3D printing has emerged as a precise and high-resolution technique to fabricate complex bioceramic parts, generating strong, ultralight, energy-absorbing, and tough materials. Despite their promise, the clinical translation of 3D-printed bioceramic implants is hampered by regulatory and reimbursement hurdles. This review analyses recent advances in vat-photopolymerization printing of bioceramics, highlighting the technical challenges and the potential of nanoscale printing to enhance the mechanical and biological functions of implants. The review also provides recommendations for regulatory frameworks, envisioning a future with the successful clinical translation of advanced 3D architectures.

Adjustment of Micro- and Macroporosity of ß-TCP Scaffolds Using Solid-Stabilized Foams as Bone Replacement.

To enable rapid osteointegration in bioceramic implants and to give them osteoinductive properties, scaffolds with defined micro- and macroporosity are required. Pores or pore networks promote the integration of cells into the implant, facilitating the supply of nutrients and the removal of metabolic products. In this paper, scaffolds are created from ß-tricalciumphosphate (ß-TCP) and in a novel way, where both the micro- and macroporosity are adjusted simultaneously by the addition of pore-forming polymer particles. The particles used are 10-40 wt%, spherical polymer particles of polymethylmethacrylate (PMMA) (Ø = 5 µm) and alternatively polymethylsilsesquioxane (PMSQ) (Ø = 2 µm), added in the course of ß-TCP slurry preparation. The arrangement of hydrophobic polymer particles at the interface of air bubbles was incorporated during slurry preparation and foaming of the slurry. The foam structures remain after sintering and lead to the formation of macro-porosity in the scaffolds. Furthermore, decomposition of the polymer particles during thermal debindering results in the formation of an additional network of interconnecting micropores in the stabilizing structures. It is possible to adjust the porosity easily and quickly in a range of 1.2-140 μm with a relatively low organic fraction. The structures thus prepared showed no cytotoxicity nor negative effects on the biocompatibility.

Additive Manufacturing of Bioceramic Implants for Restoration Bone Engineering: Technologies, Advances, and Future Perspectives.

Treating bone defects is highly challenging because they do not heal on their own inside the patients, so implants are needed to assist in the reconstruction of the bone. Bioceramic implants based on additive manufacturing (AM) are currently emerging as promising treatment options for restoration bone engineering. On the one hand, additively manufactured bioceramic implants have excellent mechanical properties and biocompatibility, which are suitable for bone regeneration. On the other hand, the designable structure and adjustable pores of additively manufactured bioceramic implants allow them to promote suitable cell growth and tissue climbing. Herein, this review unfolds to introduce several frequently employed AM technologies for bioceramic implants. After that, advances in commonly used additively manufactured bioceramic implants, including bioinert ceramic implants, bioactive ceramic implants, and bioceramic/organic composite implants, are categorized and summarized. Finally, the future perspectives of additively manufactured bioceramic implants, in terms of mechanical performance improvement, innovative structural design, biological property enhancement, and other functionalization approaches, are proposed and forecasted. This review is believed to provide some fundamental understanding and cutting-edge knowledge for the additive manufacturing of bioceramic implants for restoration bone engineering.

Calcium-to-phosphorus releasing ratio affects osteoinductivity and osteoconductivity of calcium phosphate bioceramics in bone tissue engineering

Calcium phosphate (Ca-P) bioceramics, including hydroxyapatite (HA), biphasic calcium phosphate (BCP), and beta-tricalcium phosphate (β-TCP), have been widely used in bone reconstruction. Many studies have focused on the osteoconductivity or osteoinductivity of Ca-P bioceramics, but the association between osteoconductivity and osteoinductivity is not well understood. In our study, the osteoconductivity of HA, BCP, and β-TCP was investigated based on the osteoblastic differentiation in vitro and in situ as well as calvarial defect repair in vivo, and osteoinductivity was evaluated by using pluripotent mesenchymal stem cells (MSCs) in vitro and heterotopic ossification in muscles in vivo. Our results showed that the cell viability, alkaline phosphatase activity, and expression of osteogenesis-related genes, including osteocalcin (Ocn), bone sialoprotein (Bsp), alpha-1 type I collagen (Col1a1), and runt-related transcription factor 2 (Runx2), of osteoblasts each ranked as BCP > β-TCP > HA, but the alkaline phosphatase activity and expression of osteogenic differentiation genes of MSCs each ranked as β-TCP > BCP > HA. Calvarial defect implantation of Ca-P bioceramics ranked as BCP > β-TCP ≥ HA, but intramuscular implantation ranked as β-TCP ≥ BCP > HA in vivo. Further investigation indicated that osteoconductivity and osteoinductivity are affected by the Ca/P ratio surrounding the Ca-P bioceramics. Thus, manipulating the appropriate calcium-to-phosphorus releasing ratio is a critical factor for determining the osteoinductivity of Ca-P bioceramics in bone tissue engineering.

Optimal regenerative repair of large segmental bone defect in a goat model with osteoinductive calcium phosphate bioceramic implants

So far, how to achieve the optimal regenerative repair of large load-bearing bone defects using artificial bone grafts is a huge challenge in clinic. In this study, a strategy of combining osteoinductive biphasic calcium phosphate (BCP) bioceramic scaffolds with intramedullary nail fixation for creating stable osteogenic microenvironment was applied to repair large segmental bone defects (3.0 cm in length) in goat femur model. The material characterization results showed that the BCP scaffold had the initial compressive strength of over 2.0 MPa, and total porosity of 84%. The cell culture experiments demonstrated that the scaffold had the excellent ability to promote the proliferation and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs). The in vivo results showed that the intramedullary nail fixation maintained the initial stability and structural integrity of the implants at early stage, promoting the osteogenic process both guided and induced by the BCP scaffolds. At 9 months postoperatively, good integration between the implants and host bone was observed, and a large amount of newborn bones formed, accompanying with the degradation of the material. At 18 months postoperatively, almost the complete new bone substitution in the defect area was achieved. The maximum bending strength of the repaired bone defects reached to the 100% of normal femur at 18 months post-surgery. Our results demonstrated the good potential of osteoinductive BCP bioceramics in the regenerative repair of large load-bearing bone defects. The current study could provide an effective method to treat the clinical large segmental bone defects.

Long-term histological results of ossicular chain reconstruction using bioceramic implants.

Middle ear problems are addressed using tympanoplasty, which requires a mobile tympanic membrane and secure sound-conducting mechanism. The present is a long-term, retrospective, non-controlled study on the results of ossiculoplasty using bioceramic implants of autochthonous origin and which defined the statistical relevant factors that could influence the rate of implant rejection. In a cohort of 108 patients ossiculoplasties with bioceramic implants were performed and patients were followed up clinically for a period of minimum 7 years. Several factors were identified that could influence the results of the implantation and the statistical correlations were studied. The rejection rate after 9.12 years was 21% (23 patients). Histological integration rate was 79% (85 patients), similar to results reported in literature for both bioceramic and titanium implants. Hydroxyapatite has many of the ideal characteristics required to be a good prosthesis with a high degree of biocompatibility, very low extrusion rate, low risk of disease transmission and good functional results. Although perhaps considered of historical interest, bioceramic implants are cheaper and can be produced locally, which is a great advantage for struggling economies.

Strontium combined with bioceramics for osteoporotic bone repair: Oral intake or as a dopant?

Osteoporotic bone defect repair using synthetic biomaterial-based strategies is promising but remains challenging as it requires superior efficient osteogenic effects. Due to the strong osteogenic potential of strontium (Sr), there is a growing interest in modifying inorganic porous scaffolds by incorporating Sr or combining the scaffold with strontium ranelate (SrRAN) drug administration. To compare the therapeutic effect of these two approaches, critical-sized bone defects were repaired using pure hydroxyapatite bioceramics (HA group), Sr-doped HA (SrHA group), or pure HA combined SrRAN drug oral intake (SrRAN+HA group). After 8 and 12 weeks of implantation, micro-CT analysis revealed excellent bone formation in the SrRAN+HA group compared to the SrHA group in terms of a significantly higher bone volume ratio within the defect (dBV/TV). With regard to the new bone volume ratio at the periphery of the defect (pBV/TV), the values of SrHA and SrRAN+HA in a peri-implant 500-μm region at week 12 were comparable. Furthermore, a histological analysis demonstrated that the implant and the host bone were tightly connected without any gaps in the SrRAN+HA group after week 8. In addition, SrRAN+HA expressed more Emcn/CD31 double-positive vessels and OCN protein than the SrHA group. Finally, we discovered that SrHA substantially increased the Sr concentration in the surrounding bone tissue, but no improvement in the mechanical properties was observed. Our findings indicated that, compare to Sr-dopant, implantation of bioceramics with SrRAN systematic treatment would be a more efficient method to increase new bone formation and osteointegration in critical-sized osteoporotic bone defects.

Friction and Wear Behaviors of Reduced Graphene Oxide- and Carbon Nanotube-Reinforced Hydroxyapatite Bioceramics

Friction and wear properties play an important role in the long-term in vivo performance of load-bearing bioceramic implants. In this study, the friction and wear behaviors of hydroxyapatite (HA) reinforced with reduced graphene oxide (rGO) and rGO + carbon nanotube (CNT) hybrids were studied by ball-on-disk tests to understand the effects of nanocarbon content and morphology on the composites’ tribological behaviors. The intact and worn surfaces were characterized by optical microscopy, nanoindentation, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Raman spectroscopy. We found that the incorporation of rGO and rGO + CNT hybrids in HA bioceramic both improved the friction and wear behaviors, and the highest wear resistance was achieved by employing 1 wt% rGO and 1 wt% CNT as reinforcements. The major reinforcing mechanism was the formation of carbonaceous films between the composite surfaces and counterbody, which served as solid lubrication films that resulted in a lower coefficient of friction, higher hardness, and increased hardness/modulus ratio. Importantly, CNT addition facilitated the uniform distribution of the reinforcements in the HA matrix and the pinning effects of CNT enhanced the connection between rGO and HA.

A Clinical Trial to Evaluate the Efficacy and Safety of 3D Printed Bioceramic Implants for the Reconstruction of Zygomatic Bone Defects.

The purpose of this study was to evaluate the clinical efficacy and safety of patient-specific additive-manufactured CaOSiO2-P2O5-B2O3 glass-ceramic (BGS-7) implants for reconstructing zygomatic bone defects at a 6-month follow-up. A prospective, single-arm, single-center, clinical trial was performed on patients with obvious zygoma defects who needed and wanted reconstruction. The primary outcome variable was a bone fusion between the implant and the bone evaluated by computed tomography (CT) at 6 months post surgery. Secondary outcomes, including implant immobilization, satisfaction assessment, osteolysis, subsidence of the BGS-7 implant, and safety, were assessed. A total of eight patients were enrolled in the study. Two patients underwent simultaneous reconstruction of the left and right malar defects using a BGS-7 3D printed implant. Cone beam CT analysis showed that bone fusion at 6 months after surgery was 100%. We observed that the average fusion rate was 76.97%. Osteolysis around 3D printed BGS-7 implants was not observed. The mean distance displacement of all 10 implants was 0.4149 mm. Our study showed no adverse event in any of the cases. The visual analog scale score for satisfaction was 9. All patients who enrolled in this trial were aesthetically and functionally satisfied with the surgical results. In conclusion, this study demonstrates the safety and promising value of patient-specific 3D printed BGS-7 implants as a novel facial bone reconstruction method.

The Influence of Co Additive on the Sintering, Mechanical Properties, Cytocompatibility, and Digital Light Processing Based Stereolithography of 3Y-TZP-5Al2O3 Ceramics.

Nanocrystalline 3 mol% yttria-tetragonal zirconia polycrystal (3Y-TZP) ceramic powder containing 5 wt.% Al2O3 with 64 m2/g specific area was synthesized through precipitation method. Different amounts of Co (0–3 mol%) were introduced into synthesized powders, and ceramic materials were obtained by heat treatment in the air for 2 h at 1350–1550 °C. The influence of Co addition on the sintering temperature, phase composition, microstructure, mechanical and biomedical properties of the obtained composite materials, and on the resolution of the digital light processing (DLP) printed and sintered ceramic samples was investigated. The addition of a low amount of Co (0.33 mol%) allows us to decrease the sintering temperature, to improve the mechanical properties of ceramics, to preserve the nanoscale size of grains at 1350–1400 °C. The further increase of Co concentration resulted in the formation of both substitutional and interstitial sites in solid solution and appearance of CoAl2O4 confirmed by UV-visible spectroscopy, which stimulates grain growth. Due to the prevention of enlarging grains and to the formation of the dense microstructure in ceramic based on the tetragonal ZrO2 and Al2O3 with 0.33 mol% Co the bending strength of 720 ± 33 MPa was obtained after sintering at 1400 °C. The obtained materials demonstrated the absence of cytotoxicity and good cytocompatibility. The formation of blue CoAl2O4 allows us to improve the resolution of DLP based stereolithographic printed green bodies and sintered samples of the ceramics based on ZrO2-Al2O3. The developed materials and technology could be the basis for 3D manufacturing of bioceramic implants for medicine.

Custom-made macroporous bioceramic implants based on triply-periodic minimal surfaces for bone defects in load-bearing sites

The architectural features of synthetic bone grafts are key parameters for regulating cell functions and tissue formation for the successful repair of bone defects. In this regard, macroporous structures based on triply-periodic minimal surfaces (TPMS) are considered to have untapped potential. In the present study, custom-made implants based on a gyroid structure, with (GPRC) and without (GP) a cortical-like reinforcement, were specifically designed to fit an intended bone defect in rat femurs. Sintered hydroxyapatite implants were produced using a dedicated additive manufacturing technology and their morphological, physico-chemical and mechanical features were characterized. The implants’ integrity and ability to support bone ingrowth were assessed after 4, 6 and 8 weeks of implantation in a 3-mm-long, femoral defect in Lewis rats. GP and GPRC implants were manufactured with comparable macro- to nano-architectures. Cortical-like reinforcement significantly improved implant effective stiffness and resistance to fracture after implantation. This cortical-like reinforcement also concentrated new bone formation in the core of the GPRC implants, without affecting newly formed bone quantity or maturity. This study showed, for the first time, that custom-made TPMS-based bioceramic implants could be produced and successfully implanted in load-bearing sites. Adding a cortical-like reinforcement (GPRC implants) was a relevant solution to improve implant mechanical resistance, and changed osteogenic mechanism compared to the GP implants. Statement of significanceArchitectural features are known to be key parameters for successful bone repair using synthetic bioceramic bone graft. So far, conventional manufacturing techniques, lacking reproducibility and complete control of the implant macro-architecture, impeded the exploration of complex architectures, such as triply periodic minimal surfaces (TPMS), which are foreseen to have an unrivaled potential for bone repair. Using a new additive manufacturing process, macroporous TPMS-based bioceramics implants were produced in calcium phosphate, characterized and implanted in a femoral defect in rats. The results showed, for the first time, that such macroporous implants can be successfully implanted in anatomical load-bearing sites when a cortical-like outer shell is added. This outer shell also concentrated new bone formation in the implant center, without affecting new bone quantity or maturity.

Properties of Composites with Calcium Phosphate Filled Polymer Matrix, Obtained Using Stereolithographic Printing for Ceramic Materials with Prescribed Pore-Space Architecture

The process of removing an organic component from composites (photopolymer/calcium phosphate) with complex architecture, which are obtained by 3D-printing in order to create personalized bioceramic implants, was studied. Ceramic materials with complex pore-space organization were obtained by stereolithographic printing. It is shown that the degree of polymerization of the composite influences the final density of the calcium phosphate ceramic materials with complex architecture.

On the Choice of the Architecture of Osteoconductive Bioceramic Implants

An a priori approach for the analysis of the architecture of osteoconductive bioceramic implants has been proposed. The most permeable products have been achieved in the case of the Kelvin architecture and the gyroid. The promising implant architecture is chosen to be the Kelvin model with a porosity of 70% and the pore sizes of 750 μm. The permeability of this architecture calculated to be 987 darcy for water approaches the value of trabecular bone tissue. It is found that the most rigid model among the architectures studied is the model with diamond architecture, while the most compliant are the Kelvin model and gyroid.

О выборе архитектуры остеокондуктивных биокерамических имплантатов

О выборе архитектуры остеокондуктивных биокерамических имплантатов