Ceramic Implants Research Articles

Hydroxyapatite-Based Natural Biopolymer Composite for Tissue Regeneration.

Hydroxyapatite (HAp) polymer composites have gained significant attention due to their applications in bone regeneration and tooth implants. This review examines the synthesis, properties, and applications of Hap, highlighting various manufacturing methods, including wet, dry, hydrothermal, and sol-gel processes. The properties of HAp are influenced by precursor materials and are commonly obtained from natural calcium-rich sources like eggshells, seashells, and fish scales. Composite materials, such as cellulose-hydroxyapatite and gelatin-hydroxyapatite, exhibit promising strength and biocompatibility for bone and tissue replacement. Metallic implants and scaffolds enhance stability, including well-known titanium-based and stainless steel-based implants and ceramic body implants. Biopolymers, like chitosan and alginate, combined with Hap, offer chemical stability and strength for tissue engineering. Collagen, fibrin, and gelatin play crucial roles in mimicking natural bone composition. Various synthesis methods like sol-gel, hydrothermal, and solution casting produce HAp crystals, with potential applications in bone repair and regeneration. Additionally, the use of biowaste materials, like eggshells and snails or seashells, not only supports sustainable HAp production but also reduces environmental impact. This review emphasizes the significance of understanding the properties of calcium-phosphate (Ca-P) compounds and processing methods for scaffold generation, highlighting novel characteristics and mechanisms of biomaterials in bone healing. Comparative studies of these methods in specific applications underscore the versatility and potential of HAp composites in biomedical engineering. Overall, HAp composites offer promising solutions for improving patient outcomes in bone replacement and tissue engineering and advancing medical practices.

Ceramic Implant Rehabilitation: Consensus Statements from Joint Congress for Ceramic Implantology: Consensus Statements on Ceramic Implant.

The objectives of the study group focused on the following main topics related to the performance of 1- and 2-piece ceramic implants: defining bone-implant-contact percentages and its measurement methods, evaluating the pink esthetic score as an esthetic outcome parameter after immediate implantation, recognizing the different results of ceramic implant designs as redefined by the German Association of Oral Implantology, incorporating the patient report outcome measure to include satisfaction and improvement in oral health-related quality of life, and conducting preclinical studies to address existing gaps in ceramic implants. During the Joint Congress for Ceramic Implantology (2022), the study group evaluated 17 clinical trials published between 2015 and 2021. After extensive discussions and multiple closed sessions, consensus statements and recommendations were developed, incorporating all approved modifications. A 1-piece implant design features a coronal part that is fused to the implant body or interfaces with the postabutment restoration platform, undergoing transmucosal healing. Long-term evaluations of this implant design are supported by established favorable clinical evidence. Inaccuracies in the pink esthetic score and bone-implant-contact percentages were managed by establishing control groups for preclinical studies and randomizing clinical trials. The patient-reported outcome measures were adjusted to include an individual visual analog scale, collected from each clinical study, that quantified improved oral health and quality of life. Preclinical investigations should focus on examining the spread of ceramic debris and the impact of heat generation on tissue and cellular levels during drilling. Further technical advancements should prioritize wound management and developing safe drilling protocols.

Mechanical properties of additively manufactured lattice structures composed of zirconia and hydroxyapatite ceramics

Ceramic lattices hold great potential for bone scaffolds to facilitate bone regeneration and integration of native tissue with medical implants. While there have been several studies on additive manufacturing of ceramics and their osseointegrative and osteoconductive properties, there is a lack of a comprehensive examination of their mechanical behavior. Therefore, the aim of this study was to assess the mechanical properties of different additively manufactured ceramic lattice structures under different loading conditions and their overall ability to mimic bone tissue properties.Eleven different lattice structures were designed and manufactured with a porosity of 80% using two materials, hydroxyapatite (HAp) and zirconium dioxide (ZrO2). Six cell-based lattices with cubic and hexagonal base, as well as five Voronoi-based lattices were considered in this study. The samples were manufactured using lithography-based ceramic additive manufacturing and post-processed thermally prior to mechanical testing. Cell-based lattices with cubic and hexagonal base, as well as Voronoi-based lattices were considered in this study. The lattices were tested under four loading conditions: compression, four-point bending, shear and tension.The manufacturing process of the different ceramics leads to different deviations of the lattice geometry, hence, the elastic properties of one structure cannot be directly inferred from one material to another. ZrO2 lattices prove to be stiffer than HAp lattices of the same designed structure. The Young’s modulus for compression of ZrO2 lattices ranges from 2 to 30GPa depending on the used lattice design and for HAp 200MPa to 3.8GPa. The expected stability, the load where 63.2% of the samples are expected to be destroyed, of the lattices ranges from 81 to 553MPa and for HAp 6 to 42MPa.For the first time, a comprehensive overview of the mechanical properties of various additively manufactured ceramic lattice structures is provided. This is intended to serve as a reference for designers who would like to expand the design capabilities of ceramic implants that will lead to an advancement in their performance and ability to mimic human bone tissue.

Ceramic additive manufacturing and microstructural analysis of tricalcium phosphate implants using X-ray microcomputed tomography

Additive manufacturing (AM) of ceramic bone implants from tricalcium phosphate (TCP) offers several benefits for bone regeneration and defect treatment. TCP scaffolds, e.g. featuring lattice or gyroid geometries, can effectively induce bone ingrowth and integration, showing a high potential in the treatment of large bone defects, e.g. as filler material for large bone defects. A major advantage of TCP is its osteoconductivity making it an effective choice for a broad range of orthopedic and dental applications. In addition, AM allows for the possibility to create precise, patient-specific implants with controllable mechanical properties. Those properties can be controlled by the implants' microstructure, e.g. in relation to bulk density and internal porosity. In this contribution, eleven resorbable bone implants were produced from β-tricalcium phosphate (β-TCP) in order to quantify the internal porosity in three dimensions using microcomputed tomography (μ CT). All components were manufactured using an extrusion-based process and scanned using an industrial μCT system at a voxel size of 10 μm. Two samples were physically prepared to allow a high-resolution μCT analysis at a voxel size of 1 μm. Results show that post-processed image data enables the non-destructive inspection of highly complex ceramic AM implants. Using μCT we were able to quantify internal porosity in β-TCP bone implant and quantify the geometry and distribution of wall thicknesses in the gyroid geometry. However, a detailed microstructural analysis is only possible using high-resolution μCT volume data, e.g. in relation to internal porosity. The findings emphasize that ceramic AM is able to produce complex components. However, NDT using μCT is crucial in the development of new materials and geometries. μCT provides high-resolution insights into the internal and external structure of ceramic AM components. It plays a critical role in detecting internal features, including small-scale porosity and delamination which are crucial for the integrity and functionality of medical implants. Moreover, μCT provides volumetric data that supports the design and manufacturing process at various stages, enabling an iterative approach of continuous improvement in mechanical performance and osseointegration.

Vat Photopolymerization of Sepiolite Fiber and 316L Stainless Steel-Reinforced Alumina with Functionally Graded Structures.

Alumina (Al2O3) ceramics are widely used in electronics, machinery, healthcare, and other fields due to their excellent hardness and high temperature stability. However, their high brittleness limits further applications, such as artificial ceramic implants and highly flexible protective gear. To address the limitations of single-phase toughening in Al2O3 ceramics, some researchers have introduced a second phase to enhance these ceramics. However, introducing a single phase still limits the range of performance improvement. Therefore, this study explores the printing of Al2O3 ceramics by adding two different phases. Additionally, a new gradient printing technique is proposed to overcome the limitations of single material homogeneity, such as uniform performance and the presence of large residual stresses. Unlike traditional vat photopolymerization printing technology, this study stands out by generating green bodies with varying second-phase particle ratios across different layers. This study investigated the effects of different contents of sepiolite fiber (SF) and 316L stainless steel (SS) on various aspects of microstructure, phase composition, physical properties, and mechanical properties of gradient-printed Al2O3. The experimental results demonstrate that compared to Al2O3 parts without added SF and 316L SS, the inclusion of these materials can significantly reduce porosity and water absorption, resulting in a denser structure. In addition, the substantial improvements, with an increase of 394.4% in flexural strength and an increase of 316.7% in toughness, of the Al2O3 components enhanced by incorporating SF and 316L SS have been obtained.

Finite Element Analysis of the Stress and Deformation in Bone Caused by CFR-PEEK, Titanium, and Zirconia Ceramic Implants.

Glass or carbon fiber-reinforced polyetheretherketone (CFR-PEEK) composites and zirconia ceramic have been offered as more modern implant biomaterials. This study examined the effects of zirconia ceramic implants, titanium, and CFR-PEEK on bone stress and deformation. A geometric model of a mandibular molar replaced with an implant-supported crown was created for this in vitro finite element analysis investigation. The dimensions of the implant employed in the study are 11.0 mm in length and 4.5 mm in diameter. Using finite element analysis, three implant assemblies composed of zirconium, titanium, and CFR-PEEK were produced. 150 N loads were applied both vertically and obliquely on the long axis of the implant. The von-Mises stresses and deformation were compared using ANSYS Workbench 18.0 and finite element software, with a significance threshold of P < 0.05. All three implant assemblies-zirconia, titanium, and CFR-PEEK-showed comparable stresses and deformation in bone with no appreciable variations. Zirconia and PEEK reinforced with carbon fibers (CFR-PEEK) have been found to be viable replacements for titanium in implant biomaterials.

Advancement in ceramic biomaterials for dental implants

AbstractThere has been enormous research on diagnostic and therapeutic dental methods due to the growing recognition of oral wellness. Numerous studies in this area have resulted in dental biomaterials, including polymers, metals, and acrylic resins, essential to restore teeth affected by illnesses or accidents. Compared to other biomaterials, such as metals or polymers, ceramics offer distinct features. Materials like zirconia and alumina demonstrate their high intrinsic strength, making them appropriate for biomedical applications like dental implants or artificial joints. Additionally, they have outstanding biocompatibility, which lowers the possibility of adverse effects or inflammation. Some ceramics, like hydroxyapatite (HA) and bioactive glasses, even encourage tissue integration and regeneration. Moreover, because of their adaptability, they can be precisely shaped and composed to emphasize specific characteristics. Yttria‐stabilized tetragonal zirconia offers outstanding mechanical properties and biocompatibility but faces concerns over long‐term durability due to low‐temperature degradation. To address this, researchers have developed non‐oxidic ceramics like silicon nitride and advanced oxide‐based materials like alumina‐zirconia composites, aiming to enhance the durability and reliability of biomedical applications. In this review, we highlighted the recent advancements in ceramic dental implants; examples and applications of different ceramics‐based materials, including zirconia, alumina, HA, and beta calcium phosphate, are provided in detail.

Comparison of Zirconia Implant Surface Modifications for Optimal Osseointegration.

Zirconia ceramic implants are commercially available from a rapidly growing number of manufacturers. Macroscopic and microscopic surface design and characteristics are considered to be key determining factors in the success of the osseointegration process. It is, therefore, crucial to assess which surface modification promotes the most favorable biological response. The purpose of this study was to conduct a comparison of modern surface modifications that are featured in the most common commercially available zirconia ceramic implant systems. A review of the currently available literature on zirconia implant surface topography and the associated bio-physical factors was conducted, with a focus on the osseointegration of zirconia surfaces. After a review of the selected articles for this study, commercially available zirconia implant surfaces were all modified using subtractive protocols. Commercially available ceramic implant surfaces were modified or enhanced using sandblasting, acid etching, laser etching, or combinations of the aforementioned. From our literature review, laser-modified surfaces emerged as the ones with the highest surface roughness and bone-implant contact (BIC). It was also found that surface roughness could be controlled to achieve optimal roughness by modifying the laser output power during manufacturing. Furthermore, laser surface modification induced a very low amount of preload microcracks in the zirconia. Osteopontin (OPN), an early-late osteogenic differentiation marker, was significantly upregulated in laser-treated surfaces. Moreover, surface wettability was highest in laser-treated surfaces, indicating favorable hydrophilicity and thus promoting early bone forming, cell adhesion, and subsequent maturation. Sandblasting followed by laser modification and sandblasting followed by acid etching and post-milling heat treatment (SE-H) surfaces featured comparable results, with favorable biological responses around zirconia implants.

Silk-Fabric Reinforced Silk for Artificial Bones.

Bone implants for different body parts require varying mechanical properties, dimensions, and biodegradability rates. Currently, it is still challenging to produce artificial bones with perfect compatibility with human bones. In this study, a silk-fabric reinforced silk material (SFS) composed of pure silk with exceptional biocompatibility, osteogenesis, and biodegradability is reported, and demonstrates its outstanding performance as a bone implant material. The SFS is fabricated using a simple hot-pressing technique, with degummed silk fabric as the reinforcement and silk fibroin as the matrix. The SFS as a self-reinforced composite, has exceptional mechanical properties due to the almost perfect interface between the matrix and reinforcement. More importantly, its mechanical properties, biodegradability rates, and density can be tailored by adjusting the reinforcement structure and the ratio of the reinforcement to the matrix to align with the requirements for bone implantation in different parts of the human body. Besides, the SFS can improve osteoblastic proliferation and increase osteogenic activity, which is not the case with clinically used titanium alloy artificial bone. Therefore, the SFS holds significant potential to replace conventional metal or ceramic implants in the field of medical fracture repair.

One-piece versus two-piece ceramic dental implants

In this narrative review, a structured comparison between one-piece and two-piece zirconia dental implants is highlighted. Ceramic dental implants have long ceased to be hype; on the contrary, they can offer a significant addition to the daily dental implant practice. Not only do their favourable aesthetics play a significant role, but their ability to work completely metal-free is of added value, particularly for patients with a proven allergy for Grade 5 titanium. Furthermore, the fact that peri-implantitis seems to appear only incidentally is an important supporting argument for their use as well. Whereas the original design of zirconia implants was formerly always of a one-piece/one-phase structure (the monobloc design), nowadays, two-piece/two-phase designs (the so-called hybrid concept) are also widely utilised to restore missing teeth. Both concepts have advantages and disadvantages, scientifically as well as clinically.For this paper, relevant articles from the recent scientific literature were selected from PubMed. The aim was to identify and summarise what has previously been published on one-piece versus two-piece ceramic implants. This article will compare the benefits and drawbacks of one-piece versus two-piece ceramic implants based on clinical- (design, different sizes, surgical protocol, prosthetics), scientific- (loading and eventual complications) and patient-related (costs and long-time perspectives) criteria.

Vat photopolymerization-engaged fabrication of high-performance, complex Si3N4 implants under rapid debinding efficiency

In this study, the vat photopolymerization (VP) additive manufacture technique was employed to fabricate Si3N4 ceramics implants. A photosensitive suspension with a high solid loading of 40 vol% and a low viscosity of 1.95 Pa•s at a shear rate of 30 s−1 was achieved by optimization of the composition. Particularly, as high as 50 vol% content of PPG was used in the photosensitive suspension, leading to a smooth printing and increased debinding efficiency with a heating rate up to 3 °C/min. The printed body was sintered at 1800 °C under 0.4 MPa nitrogen atmosphere, obtained the Si3N4 ceramic with a relative density of 96.08%, a fracture toughness of 5.88 MPa m1/2, a flexural strength of 677 MPa and a Vickers hardness of 16.26 GPa. A cylindric Si3N4 ceramic implant was made by the optimized suspension and printing parameters, and the implantation test in the histological section was conducted, showing a good biocompatibility after 6 weeks.

High-Performance Ceramics in Musculoskeletal Surgery: Current Use and Future Perspectives

Osteoarthritis (OA) is a prevalent disease among the elderly population, necessitating effective treatment options. Total joint arthroplasty (TJA) is a reliable surgical procedure that has shown good long-term clinical outcomes for OA. However, certain challenges, such as implant failure caused by particle-induced aseptic loosening or hypersensitivity to metal ions, remain unresolved in TJA. High-performance ceramic implants have emerged as a promising solution to address these persistent implant-related issues. This review article provides an overview of the composition and characteristics of ceramics used in TJA, highlighting their potential advantages and associated risks. While ceramic implants have demonstrated excellent performance in vivo for hip and knee arthroplasty, their bioinert behaviour is still considered a crucial factor regarding cementless options. Therefore, novel methods are investigated that seem to be able to combine the benefits of ceramic materials with an excellent osseointegration behaviour, which makes ceramics as implant materials an even stronger option for future applications.

Current state and perspectives on the use of zirconium ceramic implants in traumatology and orthopaedics

Background Ceramic materials are currently in wide demand in various fields of medicine. Zirconium ceramics demonstrate exceptional mechanical properties and biocompatibility and do not cause cytotoxic effects or allergic reactions in surrounding tissues.The objective was to present an analysis of current literature data on the use of zirconium ceramics as a bone replacement material in traumatology and orthopaedics.Materials and methods The search for publications was conducted using the databases of Scopus, PubMed and the electronic scientific library eLIBRARY in the Russian and English languages using the keywords: bioceramics, bone, bone defect, zirconate, zirconium ceramics, bone tissue engineering, implant, scaffold, augment, biointegration, bioactivity. Depth of search for scientific papers was from 2000 to 2023.Results and discussion Zirconium dioxide is the main ceramic bioinert material. The study presents the characteristics of ZrO2 as a bone replacement material and its comparison with titanium implants. Data are presented on various strategies for improving zirconium bioceramics: improving the surface of the material by physical and chemical methods, obtaining volumetric porosity, including using additive technologies, creating composite materials, and developing bioactive coatings. New methods of creating zirconium ceramics compatible with living tissues containing bioactive ions that promote both osseointegration and bone tissue regeneration have been actively studied.Conclusions Zirconium dioxide ceramics appear to be a promising alternative to titanium implants in terms of mechanical strength, biological functionality, chemical stability, osseointegration, and antibacterial properties. Future experimental and clinical studies will further improve zirconium ceramics.

Numerical analysis of the mechanical behavior of ceramic dental implants based on Ce-TZP/Al2O3 composite

This study aimed to identify the potential use of the ceramic composite ZrO2(CeO2)–Al2O3 as a dental implant due to its intrinsic geometry and different masticatory loads based on finite element simulations. Ceramic samples were sintered at 1500 °C-2h, and characterized: The mechanical properties of the ceramic composite (hardness, fracture toughness, flexural strength, Young's Modulus, and Poisson ratio) were determined, in addition to the relative density and its structural characteristics. Commercial dental implant designs (incisal and third-molar) on CAD models were used in this study as an initial implant geometry applied in a typical simulated mandible anatomy. Finite element models were generated for implant geometries using CAD and CAE techniques. Loading cases were considered based on different intensities (100–500 N) and orientation angles to the implant axis (0° and 45°) to reproduce human masticatory conditions. For comparison purposes, the numerical predictions were compared with finite element simulations of gold-standard titanium implants. Ce-TZP/Al2O3 sintered ceramics showed flexural strength of 952.6 ± 88 MPa, hardness and fracture toughness of 1427 ± 46 HV and 11.3 ± 0.4 MPa m1/2, respectively, beside Young's modulus of 228.3 ± 65 GPa and Poisson ratio of 0.28. For both Ce-TZP/Al2O3 dental implant geometries, the implant prototypes showed adequate mechanical behavior regardless of the masticatory load value or the orientation angle applied in the simulations: All finite element predictions are lower than the values established by Mohr Coulomb's failure criterion, allowing the feasibility, preliminarily, of the proposed ceramics for dental implant applications without fracture risk.

DLP 3D printing of TiO2-doped Al2O3 bioceramics: Manufacturing, mechanical properties, and biological evaluation

Ceramic-based biomaterials are generally produced using conventional manufacturing methods. The traditional manufacturing methods have limitations, such as material loss and a slow production process when creating personalized and complex ceramic implants. These limitations reduce the efficiency and success rate of the product. 3D printers, which are additive manufacturing methods, are a technology that enables tiny and sensitive parts to be produced quickly in the desired design. In the present study, TiO2-doped Al2O3 bioceramic parts with complicated shapes were fabricated using digital light processing (DLP) 3D printing technology. Furthermore, the mechanical, structural, and biocompatibility features of these parts were studied. The rheology studies revealed that a slurry with a solid powder loading of 50% had a suitable viscosity for 3D printing. After sintering bioceramic parts, the sintered bodies reduced significantly, with a maximum shrinkage of 41.98%. The relative density of Al2O3 ceramic decreased from 82.02 to 72.72% with 5 wt% TiO2 addition. The XRD results revealed that TiO2-doped Al2O3 bioceramic has three crystalline phases consisting of corundum (α-Al2O3), titanium dioxide (TiO2), and aluminum pentaoxotitanate (Al2TiO5). By adding 5 wt% TiO2, the compression and flexural strengths of Al2O3 increased to 3.25 to 7.07 MPa and 1.07 to 4.24 MPa, respectively. The biological test results demonstrated a high percentage of cell adhesion and proliferation confirmed by high biocompatibility. The findings show that DLP-3D printing techniques could be used to fabricate ceramics for various applications, including biomedical and dental applications, at low cost.

Survival of unconstrained ceramic wrist joint implants

Introduction Survival of implants is an important indicator of improvement in the patient's quality of life. In foreign literature, the issue of implant survival finds special attention.The aim of the work was to evaluate the efficacy and survival of an unconstrained ceramic wrist joint endoprosthesis.Materials and methods We analysed 83 cases of total wrist arthroplasty with an unconstrained ceramic implant at long-term follow-up. At the Novosibirsk RSITO, total wrist arthroplasty was performed in 81 patients with severe changes in the wrist joint from 2011 to 2021. Two patients underwent arthroplasty on two joints. A retrospective uncontrolled cohort study was conducted which divided the hospitalized patients into three groups according to the etiological cause of the disease. Radiological methods were used to control the state of the implant (radiography in two projections and CT-scans of the wrist joint). For binary indicators, the number, rates and 95 % confidence interval of frequencies were calculated according to the Wilson formula in the groups. Comparison was carried out by Fisher's exact two-sided test. The p-error was corrected using the Benjamini – Hochberg method. Kaplan – Meier curves were constructed for survival analysis. The groups were compared using a generalized chi-square test.Results Each case of repeated surgical intervention was evaluated from the standpoint of selected groups. Depending on the time elapsed from surgery to revision, we calculated the time frame for overall and group survival of the components of the wrist joint endoprosthesis. The causes and scope of surgical revision are presented.Discussion There are no data on the survival of unconstrained ceramic wrist joint implants in the foreign literature. Graphic images according to a proposal for the division of the orthopaedic postoperative period are presented. Conclusions 1. Intermediate conclusions in regard to total arthroplasty with an unconstrained ceramic endoprosthesis of the wrist joint inspire optimism in obtaining a stable positive effect of motion range lost due to the degenerative process in the wrist joint. 2. An 11-year follow-up period demonstrates that the survival rate of an unconstrained ceramic wrist endoprosthesis is 88 %.

The application of 3D printing in helping the disabled

3D printing technology has a wide range of applications in the medical field, one of which is for bone reconstruction and repair. Through 3D printing technology, artificial bone tissue or implants of various shapes, sizes, and materials can be produced. These implants can be used to replace damaged natural bones, resulting in relatively significant effects on bones. First of all, 3D printing technology can be personalized designed and manufactured according to the specific situation of the patient, enabling the repaired implant to better adapt to the physical characteristics of the patient, achieving better improvement and treatment effects. In addition, 3D printing can generate implants with internal irregular structures (such as grid shaped, honeycomb shaped, etc.) that can promote the attachment of biomaterials and the growth of bone cells, accelerating bone healing. Secondly, 3D printing technology can enable doctors and patients to better understand the shape and structure of implants, thereby improving communication and collaboration, and improving the accuracy of surgical treatment. Similarly, 3D printing technology can also generate virtual simulation models through which doctors can conduct surgical planning and demonstration, reducing the risk and difficulty of surgery. Finally, because 3D printing technology can use a variety of different materials, it is possible to manufacture various implants, including metals, plastics, ceramics, and so on. These materials have their own characteristics and can play an important role in bone repair and reconstruction. For example, metal implants can provide better mechanical support and structural stability, while ceramic implants have better biocompatibility and corrosion resistance.

Infrared irradiation to drive phosphate condensation as a route to direct additive manufacturing of oxide ceramics

AbstractThis paper introduces a fast, low‐temperature, pressureless process to chemically bind ceramic parts with the help of infrared (IR) irradiation and phosphate binder condensation. Ceramic components are synthesized from slurries of ceramic powders and Al(H2PO4)3 binder that are irradiated with short‐waved IR light capable of heating the system to 350°C. This irradiation is found to be sufficient to drive phosphate condensation, binding the ceramic powders together within a matter of seconds. The IR‐irradiated components show an increase in density and Vickers hardness. Layer‐by‐layer spraying and irradiation is demonstrated as a route to additive manufacturing using various ceramic chemistries. While further optimization is needed to control desired microstructure, this process of using chemically bonded ceramic binders with IR heating for additive manufacturing shows the potential to find applications in various ceramic systems, including refractories, bone implants, electronics, and thermal barrier coatings.

Реабилитационные технологии в ортопедической стоматологии с применением керамических имплантатов.

Studies have shown that up to 6% of the population have an allergic reaction to titanium, which can lead to implant loss (non-integration or rejection) and peri-implantitis. At the same time, for more than 25 years, zirconium dioxide (ZrO2) has been successfully used as a material for the manufacture of suprastructures and retainers of dental implants in metal-free restorations, which demonstrates excellent biomechanical properties, such as high fracture toughness and flexural strength, and also ensures successful osseointegration. The European Society for Ceramic Implantology (ESCI) global survey on the performance of ceramic implants confirmed the benefits of zirconia in terms of biocompatibility and a weak association with inflammation. The review of the literature made it possible to identify a number of advantages of modern technologies in orthopedic dentistry using ceramic implants, which make it possible to improve the quality of providing orthopedic dental care to the population in terms of safety and reliability.

Mechanics Predicts Effective Critical-Size Bone Regeneration Using 3D-Printed Bioceramic Scaffolds.

3D-printed bioceramic scaffolds have gained popularity due to their controlled microarchitecture and their proven biocompatibility. However, their high brittleness makes their surgical implementation complex for weight-bearing bone treatments. Thus, they would require difficult-to-instrument rigid internal fixations that limit a rigorous evaluation of the regeneration progress through the analysis of mechanic-structural parameters. We investigated the compatibility of flexible fixations with fragile ceramic implants, and if mechanical monitoring techniques are applicable to bone tissue engineering applications. Tissue engineering experiments were performed on 8 ovine metatarsi. A 15 mm bone segment was directly replaced with a hydroxyapatite scaffold and stabilized by an instrumented Ilizarov-type external fixator. Several in vivo monitoring techniques were employed to assess the mechanical and structural progress of the tissue. The applied surgical protocol succeeded in combining external fixators and subject-specific bioceramic scaffolds without causing fatal fractures of the implant due to stress concentrator. The bearing capacity of the treated limb was initially altered, quantifying a 28-56% reduction of the ground reaction force, which gradually normalized during the consolidation phase. A faster recovery was reported in the bearing capacity, stiffening and bone mineral density of the callus. It acquired a predominant mechanical role over the fixator in the distribution of internal forces after one post-surgical month. The bioceramic scaffold significantly accelerated in vivo the bone formation compared to other traditional alternatives in the literature (e.g., distraction osteogenesis). In addition, the implemented assessment techniques allowed an accurate quantitative evaluation of the bone regeneration through mechanical and imaging parameters.