Ceramic Resin Research Articles

All ceramic resin bonded fixed partial dentures: What's new?

All ceramic resin bonded fixed partial dentures: What's new?

Hydraulic pressure resistance of the ceramic resin composite buoyancy materials based on cylindrical tube configuration

Due to high modulus, high strength and low water absorption of the 99.5% alumina ceramic, the tubular ceramic resin composite (TCRC) has been designed and fabricated, which can provide a potential option for the deep-sea buoyancy materials. The reliability and applicability of TCRC under hydrostatic pressure are systematically discussed by means of theory, experiment and simulation. Circumferential instability and strength failure are two possible failure modes of the TCRC through theoretical analysis. The study indicates that the load-bearing capacity of TCRC decreases with the increase of the number of vertical/horizontal tube arrays m, the ratio of the inner to outer radius r/Rc of the ceramic tube or the ratio of the length to the outer radius L/Rc of the ceramic tube. Conversely, the load-bearing capacity of TCRC increases with the increase in the modulus of matrix phase Er. In addition, TCRC with parameters of “r/R-0.93/0.91-3X3-L40-E3.18” has excellent performance through experimental verification. That is, the core density and hydrostatic strength of the TCRC are 0.67 g/cm3 and 150.6 MPa, respectively. Better stated, our designed buoyancy material can be applied in the deep-sea environment of 12000m, which is the deepest spot on the ocean floor ever explored. The excellent performance of TCRC verifies the feasibility of ceramic circular honeycomb configuration in the application of hydrostatic pressure environment. Meanwhile, the buoyancy materials used in different water depths can be designed by changing the L/Rc or r/Rc of the round tube in circular honeycomb.

Digital light processing of sodium-beta-alumina ceramic electrolytes

Solid-state electrolyte structures using sodium-beta-alumina oxide ceramics, have been fabricated for the first time, using digital light processing; a vat photopolymerisation additive manufacturing process. Green bodies were shaped using a high solids loading ceramic resin of 46 vol.% (72 wt.%) and were then thermally binder removed and sintered. Conventionally sintered at 1580 °C for 5 min, additively manufactured electrolyte test samples exhibited an ionic conductivity of σ = 0.18 S·cm-1 at 300 °C, an activation energy of conduction Ea = 0.38 eV and density of ρ = 3.19 ± 0.01 g·cm-3 (relative density 98%) along with a retention of 91 wt.% of the desirable β’’ rhombohedral phase. Results suggest that digital light processing of sodium polyaluminates is a very promising approach for manufacturing geometrically complex monolithic ceramic electrolytes for future applications in electrochemical energy storage.

Stereolithography of ceramic scaffolds for bone tissue regeneration: Influence of hydroxyapatite/silica ratio on mechanical properties

In this paper, the results obtained in the development of ceramic resin feedstock for stereolithography are shown. Hydroxyapatite and silica are used as source of ceramic. Hydroxyapatite is extracted from bovine bone, which enhances bioactivity of ceramic scaffold. The influence of hydroxyapatite amount in polymer-based slurry on the viscosity and printability of feedstock is explored. Hydroxyapatite and silica containing scaffolds are successfully obtained by stereolithography. Influence of hydroxyapatite/silica ratio on the bioactivity, biodegradability and mechanical properties of the scaffolds is also studied. It was observed that higher concentrations of hydroxyapatite led to improved mechanical strength of the scuffolds but increased viscosity of the slurry, affecting printability. Cell viability assays and cell visualization experiments indicated that the scaffolds not cause significant cell toxicity.

Evaluation of the Color Stability of Three Resin-Ceramic Materials Using a Spectrophotometer and a Digital Photography Software.

Computer-aided design/computer-aided manufacturing (CAD/CAM) resin ceramics allow easier milling than glass ceramics but are suspected to be more stainable. Although Photoshop® is widely used for picture analysis, its potential for shade selection has not been properly assessed. Purpose primary: To evaluate the color stability of three CAD/CAM resin ceramics and Lithium Disilicate. Secondary: to compare the color evaluation between a spectrophotometer (Vita Easyshade compact) and Photoshop software. Three CAD/CAM resin ceramic materials (n = 10) and a fourth group of lithium disilicate were used. Half of each group were thermocycled (5°C and 55°C; 3000 cycles). All samples were immersed in colored beverages (coffee, tea and red wine) for 30 days. Values were obtained by spectrophotometry and photographs analyzed using Photoshop software. The parameters measured were CIEL*a*b, and the color difference (ΔE) was analyzed. A mixed model test was used to compare the results through time and materials (α = 0.05). The comparison between the spectrophotometer and Photoshop results was performed using the bivariate Pearson's correlation test. Lithium disilicate glass ceramic exhibited less color change (ΔE = 14) than resin ceramics (15.7 < ΔE < 18.7). The least change was noted with GC Cerasmart (ΔE = 15.7) followed by Vita Enamic (ΔE = 17*) and Brilliant Crios (ΔE = 18.7*). Spectrophotometer and Photoshop values showed low correlations. Resin ceramics may suffer from color change in clinical use. Photoshop is technique sensitive; pictures are easily affected by the light conditions and camera settings.

Low-Cost, Compact Quadrupole Mass Filters with Unity Mass Resolution via Ceramic Resin Vat Photopolymerization.

This study reports novel, compact, and additively manufactured quadrupole mass filters (QMFs) with adequate filtering performance for practical mass spectrometry applications. The QMFs are monolithically fabricated via vat photopolymerization of glass-ceramic resin using 57µm×57µm×100µm voxels, and selective electroless plating of nickel-boron. Experimental characterization of QMF prototypes at 1.74MHz using FC-43 yields 131Da peaks with 0.50Da full width at half maximum (260 resolution), surpassing the resolution of reported miniaturized counterparts under similar conditions, and being on par with commercial, non-miniaturized, heavier devices. The sensitivity of the 3D-printed devices is estimated at 0.13mATorr-1 (comparable to that of optimized, commercial counterparts), while the devices attained up to 250Da of mass range (limited by the driving electronics). The work is of interest to low-cost, capable mass spectrometry, 3D-printed instruments, and in-space manufacturing of complex instrumentation.

Development of Photo-Polymerization-Type 3D Printer for High-Viscosity Ceramic Resin Using CNN-Based Surface Defect Detection.

Due to the high hardness and brittleness of ceramic materials, conventional cutting methods result in poor quality and machining difficulties. Additive manufacturing has also been tried in various ways, but it has many limitations. This study aims to propose a system to monitor surface defects that occur during the printing process based on high-viscosity composite resin that maximizes ceramic powder content in real time using image processing and convolutional neural network (CNN) algorithms. To do so, defects mainly observed on the surface were classified into four types by form: pore, minor, critical, and error, and the effect of each defect on the printed structure was tested. In order to improve the classification efficiency and accuracy of normal and defective states, preprocessing of images obtained based on cropping, dimensionality reduction, and RGB pixel standardization was performed. After training and testing the preprocessed images based on the DenseNet algorithm, a high classification accuracy of 98% was obtained. Additionally, for pore and minor defects, experiments confirmed that the defect surfaces can be improved through the reblading process. Therefore, this study presented a defect detection system as well as a feedback system for process modifications based on classified defects.

Novel Bone Void Filling Cement Compositions Based on Shell Nacre and Siloxane Methacrylate Resin: Development and Characterization.

Shell nacre from Pinctada species has been extensively researched for managing bone defects. However, there is a gap in the research regarding using shell nacre powder as a cement with improved biological and physicochemical properties. To address this, bone void filling cement was formulated by incorporating shell nacre powder and an organically modified ceramic resin (ormocer). The shell nacre powder was specifically processed from the shells of Pinctada fucata and analysed using thermogravimetric analysis (TGA), X-ray diffraction spectroscopy, Fourier transform infrared (FTIR), and Raman spectroscopy, confirming the presence of organic constituents and inorganic aragonite. Trace element analysis confirmed the eligibility of shell nacre powder for biomedical applications. Next, the ormocer SNLSM2 was synthesized through a modified sol-gel method. FTIR, Raman, TGA, and transmission electron microscopy studies revealed the presence of a ladder-structured siloxane backbone and methacrylate side chain. To develop chemical curable composite shell nacre cement (SNC), different amounts of shell nacre (24%, 48%, and 72%) were added to the SNLSM2 resin, and the impact on the physicochemical properties of the cement was studied. Among the compositions, SNC 72 exhibited significantly lower linear polymerization shrinkage (0.4%) and higher compressive (>100 MPa) and flexural strength (>35 MPa). SNC 72 was radiopaque, and the exotherm generated during the cement curing was minimal. Cytotoxicity studies with L929 cells revealed the non-cytotoxic nature of the cement. Overall, the findings of this study prove that the shell nacre cement is a promising candidate for managing bone voids.

Effects of powder properties on the 3D printing of BaTiO3 ceramic resins by stereolithography

Stereolithography is a layer-by-layer building fabrication technique enabling production of advanced ceramic 3D shapes that are not achievable by other methods. Critical parameters of stereolithography are associated with the preparation of a ceramic resin exhibiting suitable rheological and optical properties, as well as tunable curing property to achieve the desired level of resolution of complex 3D parts. However, tailoring the cure depth for each layer is challenging for functional ceramics due to their high refractive index giving increased light scattering. Here, the stereolithography 3D printing of BaTiO3 ceramic resins is investigated by employing a desktop 3D printer (λ = 405 nm) and a commercial base resin. The effects of two BaTiO3 powders with different size distributions (one micro-sized powder with grains in the range 1–20 µm, and one agglomerated nano-sized powder in the range 60–100 nm), on the viscosity and curing characteristics of the ceramic resins were investigated. It is shown that the nano-sized powder resulted in increased viscosity, increased scattering, and reduced cure depth compared to the micro-sized BaTiO3 ceramic resin. In general, the cure depth decreased with increasing ceramic loading. Successful prints were obtained for an overcuring of at least 40% between layers to assure good adherence between the layers. The printing properties of the ceramic resins from both powders were suitable for printing green parts with 50 µm layer thickness.

Scalable Manufacturing of Mechanical Robust Bioinspired Ceramic-Resin Composites with Locally Tunable Heterogeneous Structures.

Lightweight structural materials with a unique combination of high stiffness, strength, toughness, and hardness, are highlydesired yet challenging to be artificially fabricated. Biological structural materials, on the other hand, ingeniously integrate multiple mutually exclusive mechanical properties together relying on their hierarchically heterogeneous structures bonded with gradient interfaces. Here, a scalable bottom-up approach combining continuous nanofiber-assisted evaporation-induced self-assembly with laminating, pressure-less sintering and resin infiltration is reported to fabricate bioinspired heterogeneous ceramic-resin composites with locallytunable microstructure to fulfill specific properties. A gradient interlayer isintroduced to provide a gradual transition between adjacent heterogeneous layers, effectively alleviating their property mismatch. The optimized heterogeneous nacre-like composite, as a demonstration, exhibits an attractive combination of low density (≈2.8gcm-3 ), high strength (≈292MPa), toughness (≈6.4MPam1/2 ), surface hardness (≈1144 kgfmm-2 ) and impact-resistance, surpassing the overall performance of engineering alumina. This material-independent approach paves the way for designing advanced bioinspired heterogeneous materials for diverse structural and functional applications.

Entering a New Dimension in Powder Processing for Advanced Ceramics Shaping.

Filigree structures can be manufactured via two-photon polymerization (2PP) operating in the regime of nonlinear light absorption. For the first time, it is possible to apply this technique to the powder processing of ceramic structures with a feature size in the range of the critical defect sizes responsible for brittle fracture and, thus, affecting fracture toughness of high-performance ceramics. In this way, tailoring of advanced properties can be achieved already in the shaping process. Traditionally, 2PP relies on transparent polymerizable resins, which are diametrically opposed to the usually completely opaque ceramic resins and slurries. Here a transparent and photocurable suspension of nanoparticles (resin) with very high mass fractions of yttria-stabilized zirconia particles (YSZ) is presented. Due to the extremely well-dispersed nanoparticles, scattering of light can be effectively suppressed at the process-relevant wavelength of 800nm. Sintered ceramic structures with a resolution of down to 500nm are obtained. Even at reduced densities of 1-4g cm-3 , the resulting compressive strength with 4.5GPa is equivalent or even exceeding bulk monolithic yttria-stabilized zirconia. A ceramic metamaterial is born, where the mechanical properties of yttria-stabilized zirconia are altered by changing geometrical parameters, and gives access to a new class of ceramic materials.

Thermal shock resistance of additively manufactured gas-permeable SiO2 ceramic structures for HIP-quench applications

The increasing demand for hot isostatic pressing (HIP) means that a reliable and efficient operation of modern HIP units with fast cool capability is indispensable. A key factor for efficient operation is the ceramic crucible used as the load basket. Its task is to keep as much of the HIPed parts as possible effectively within the hot zone and to prevent them touching the furnace wall. This work focuses on designing a gas-permeable ceramic structure with a high thermal shock resistance that can be scaled up to a load basket for future HIP applications. Stereolithography (SL) 3D printing of a ceramic resin is employed to build various scalable framework structures inspired by nature and by existing engineering applications. Thermal shock tests with water quenching reveal that framework structures with evenly distributed triangular bracings offer the highest flexural strength, whereas auxetic structures are best at retaining their flexural strength after thermal shock.

Mechanical and thermal ablative behavior of ceramic-modified lightweight quartz felt reinforced phenolic aerogel

This paper reports a ceramic-modified lightweight composite for surface thermal protection of re-entry or hypersonic vehicles. The mixed ceramic resin is used to bond fiber felts, and then synthesize phenolic aerogels in situ inside felts. Ceramic resins are enriched on the fiber surfaces and intersections, protecting the composite's porous structure under high temperatures using ceramization and ablative products. The XY directional compressive strength is 6.48 MPa, and the Z directional full volume rebound compressive strength is 0.64 MPa. For the high-temperature ablation, the composite has a linear ablation rate of 0.017 mm/s, a weight loss rate of 0.024 g/s, and a backside temperature of 61.6 °C. Finite element modelling shows that the heat-affected zone is mainly concentrated in the upper part of the composite, and the backside temperature is below 200 °C. The prepared composites have a wide application in thermal protection under high heat flow aerodynamic ablation conditions.

PotteryVR: virtual reality pottery

Handcrafting ceramic pottery in the traditional method or virtual reality (VR) with intricate surface details is still challenging for the ceramic and graphic artist. Free-form pottery modeling can be efficiently geometrically modeled with the right tools with detailed 3D print outputs, yet challenging to be manufactured using traditional art. The new advanced pottery VR simulation is a promising method to recreate the traditional pottery simulation for a better experience with some barriers. The challenges that arise from surface detail in pottery are a tedious task accomplished by mesh blending and retopology. This paper focuses on refining the VP application’s performance by adding unique sound resonance as a more likely infinite geometric phenomenon textures, blending it into the basic shapes. This paper combines creativity and visual computing technologies such as VR, mesh blending, fixing errors, and 3D printing to bring the ceramic artist’s imagination to life. We have used sound resonance with virtual pottery (VP) systems refinements to demonstrate several standard pottery methods from free form deformed pottery, retopology, mesh blended for surface details, and 3D printed pottery with materials including polymer and ceramic resins.

Lightweight quartz fiber fabric reinforced phenolic aerogel with surface densified and graded structure for high temperature thermal protection

This paper reports a lightweight thermal protection composite with good anti-ablation and thermal insulation properties for service in high temperature environment. The needle quartz fiber (NQF) reinforced phenolic resin aerogel (PRA) composites with surface densification and graded structure were prepared using a mixture of ceramic resin (CR) as the surface layer and phenolic resin (PR) as the internal layer. The Tensile and bending strength of the dense layers were up to 39.22 MPa and 57.22 MPa, respectively. The complete volume rebounded compressive strength of the internal layer was 0.25 MPa and 2.94 MPa in Z and XY directions. In the ablation experiment, the backside temperature peaked at 52 °C within 3 min and 127 °C within 5 min whereas the surface temperature exceeded 1100 °C. Furthermore, the ablated surface remained flat and had a near ablation rate even at a temperature exceeding 1700 °C. The composites which combine insulation and anti-ablation exhibit a prospect in the fields of aerospace and retardant insulation.

Adhesion to a Zirconia-reinforced Lithium Silicate Ceramic: Effects of Ceramic Surface Treatments and Resin Cements

This study had the objective to test the effect of ceramic surface treatments on the microshear bond strength (μSBS) of different resin cements to a zirconia-reinforced lithium silicate (ZLS). ZLS blocks were sectioned, embedded in acrylic resin, and then allocated into nine groups considering two study factors: "ceramic surface treatment" (HF - hydrofluoric acid; EP - self-etching primer; TBS - tribochemical silica coating) and "resin cements" (nMDP - without MDP monomer; MDP - with MDP monomer; SA - self-adhesive). Starch tubes (n=36) were placed on the treated ceramic surface and the cement was applied. Starch tubes were removed after 24 hours of storage, and the specimens were thermocycled (5,000×; 5°C-55°C). Next, the μSBS test was performed using the wire-loop technique, and topographic and failure analyses were performed. The factors "ceramic surface treatment" and "resin cement" statistically influenced the μSBS results. Considering the surface treatment factor, the TBS produced statistically lower values when the MDP resin cement was applied, being only similar to the MDP plus EP group. For the resin cement factor, no difference was found for nMDP and SA groups, apart from the surface treatments. Failure analysis showed that the groups treated with EP had a greater number of pre-test failures. The surface treatments induced noteworthy topographic alterations when compared to control (no treatment). The ZLS ceramic surface treatment with tribochemical silica coating associated with the MDP-containing resin cement resulted in lower bond strength values.

Photopolymerization of Ceramic Resins by Stereolithography Process: A Review

Stereolithography is known as one of the best Additive Manufacturing technologies in terms of geometrical and dimensional precision for polymeric materials. In recent years, a lot of studies have shown that the creation of ceramic resins, through a particular combination of monomeric components and ceramic powders, allows to obtain complex shape geometries thanks to the photopolymerization process. This review highlights the characteristics and properties of ceramic resins, peculiarities of the ceramic stereolithography processes, up to the relationship between the composition of the ceramic resin and the complexity of the post-processing phases. The comparison of different studies allows outlining the most common steps for the production of ceramic resins, as well as the physical and chemical compatibility of the different compounds that must be studied for the good feasibility of the process.

Evaluation of the Fatigue Strength of a CAD-CAM Nanoceramic Resin Crown on Titanium and Zirconia-Titanium Abutments

A computer-aided design/computer-aided manufacturing (CAD/CAM) resin block material for restoration of single-implant abutments can be milled and cemented on an optimized standard titanium abutment as a cheaper solution or, alternatively, individualization of the crown–abutment connection is required to fulfill the same mechanical requirements. The aim of this study was to evaluate how different structural and geometric configurations of the abutment influence the resistance of a nano ceramic resin crown (NCRC). During the test, 30 implants with an internal conical tapered configuration were considered. Each implant received a standard titanium abutment: in group 1, NCRCs were directly bonded to the titanium abutments; in group 2, NCRCs were cemented on a customized zirconia framework and then cemented on a standardized titanium abutment. Three crowns of each group were submitted to a static load test until failure. The remaining crowns were submitted to a fatigue test protocol with a dynamic load. The static and dynamic test showed earlier failure for group 1. In group 1, complete breaking of NCRCs was observed for all samples, with an almost total titanium abutment exposition. In the static tests, group 2 showed a mode of failure that involved only the crown, which partially debonded from the zirconia abutment. Within the limitations of the present preliminary study, it was possible to conclude that the shape of the abutment mainly influences the fatigue strength compared to the static tensile strength. The results of the performed test show that NCRC bonded to the customized zirconia abutments, and presented a 75% survival rate when compared to the same material bonded directly to a standard titanium abutment.

Structural behavior of 3D-printed sandwich beams with strut-based lattice core: Experimental and numerical study

This study aims to introduce 10 strut-based topologies which have been used to study the three-point bending and compressive responses of the lattice-core sandwich beams. All printed samples have fabricated from ceramic resin via digital light processing (DLP) 3D technology. Besides, three experiments have been performed to investigate the effects of ultrasonic cleaning time, ultraviolet (UV) radiation time, and effects of the time interval between 3D printing and experimental test on the mechanical behavior of UV sensitive resin. Also, the mechanical properties have been studied (e.g., compression, tensile, and flexural properties). According to experimental data, Star and Diamond topologies had maximum flexural and compression strength about 458 N and 450 N, as well as Grid and Re-entrant Honeycomb structures had minimum flexural and compression strength almost 119 N and 162 N, respectively. To evaluate the experimental results, 10 topologies (4 structures for flexural and 6 structures for compressive testing) were simulated through finite element analysis (FEA). Then, the deflection values and mechanical behaviour of specimens were compared with each other. Experimental and FE results confirmed each other, completely. As a result, it was evident that some structures, such as Grid had a better response under compressive load while having the weakest response to three-point bending. Furthermore, the Octet-truss structure resisted much greater deflection. On the other hand, the results indicate that Star and Diamond structures have higher stiffness and they are the best choice in the sandwiches under compressive and bending. These significant findings illustrate that some of the structures studied may have the potential to be considered as alternatives to optimal structures in the 3D-printed sandwich panels.

Effect of dispersants on structural integrity of 3D printed ceramics

AbstractCeramic 3D printing based on stereolithography is an excellent alternative to overcome drawbacks of conventional subtractive manufacturing for 3D shape control. Optimization of photocurable ceramic slurry is one of the most essential conditions to achieve favorable 3D printed structures using SL. Homogeneity of ceramic particle dispersion in photocurable resin is particularly important to optimize ceramic suspension. Dispersant plays a significant role in increasing homogeneity. Dispersant in photocurable ceramic resin has an additional effect on photocurability and integrity of 3D printed green body. We herein discuss how dispersants influence 3D printing conditions based on stereolithography using various commercially available dispersants of BYK series such as BYK103, BYK111, BYK180, BYK182, and BYK2001. Both BYK111 and BYK180 showed better performances than others because of their lower volatilities under general temperature condition during a printing process. Both solubility and decomposition temperature of dispersants largely influenced the structural quality after washing and debinding processes. This study provides worthy information to design photocurable ceramic suspension for various types of ceramic materials.