Search

Purpose: To compare the translucency parameters and masking abilities of different monolithic CAD/CAM ceramics placed on different-colored substructures. Materials and Methods: Square-shaped specimens (12 × 12 × 1.5 mm) were prepared from feldspathic (C), leucite (EMP), lithium disilicate (e.max), zirconiareinforced lithium silicate (VS), resin nanoceramic (LU), polymer-infiltrated ceramic (VE), hybrid nanoceramic (GC), monolithic zirconia (TZI), and composite resin (TC) blocks (n = 10 per material). After mechanical polishing, the translucency parameter (TP) was calculated. Then, each ceramic specimen was measured on eight substructures, and the color difference between ND2 and each substrate was calculated with the CIEDE2000 formula. TP values were analyzed with one-way ANOVA and Games-Howell tests, and the color differences indicating masking ability were analyzed with two-way ANOVA and Tukey HSD tests. Results: The highest TP was observed in TC, followed by LU, EMP, C,GC, e.max, VS, VE, and TZI. The E00 color difference values of TZI, VS, and VE on all abutment colors, except for ND9, were below the acceptable threshold value. Conclusions: All monolithic ceramic materials used in the study masked the ND1 and ND3 substrates. The ND9, representing severely discolored or devitalized preparations, could not be masked by any monolithic CAD/CAM ceramics used in the study. [ABSTRACT FROM AUTHOR]

Purpose: To compare the masking ability of monolithic CAD/CAM veneers placed over different resin cement shades and substrate colors. Materials and Methods: Veneers were milled from four different monolithic CAD/CAM restorative materials: feldspathic ceramic (VMII), lithium disilicate ceramic (Emax CAD), zirconiareinforced lithium silicate ceramic (VS), and high-translucency zirconia ceramic (YZ-XT). Veneers were luted on natural tooth-colored (ND1) or discolored substrates (ND3 or ND5) using two different resin cement shades (opaque white or translucent). Each CAD/CAM material, resin cement shade, and substrate combination comprised 9 sample veneers (N = 216). Color parameters were obtained using a dental spectrophotometer before and after luting. Color differences (E00) were calculated using CIEDE2000 formula and compared to perceptibility (P = .81 E00 units) and acceptability (AT = 1.77 E00 units) visual thresholds. Color variation data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests with Bonferroni-Holm correction (a = .05). Results: The highest E00 value was obtained in the VMII group placed over a discolored substrate, followed by the Emax CAD, YZ-XT, and VS groups. The effect of material types on E00 values was significantly observed when the veneers were luted on discolored substrates using translucent resin cement (P < .05). Conclusions: Restorative material type, substrate color, and resin cement shade affect the masking ability of monolithic CAD/CAM laminate veneers. [ABSTRACT FROM AUTHOR]

In this article, we investigate the structural relaxation of lithium silicate glass during isothermal physical aging by monitoring the temporal evolution of its refractive index and enthalpy following relatively large (10–40 °C) up- and down-jumps in temperature. The Kohlrausch–Williams–Watts function aptly describes the up- and down-jump data when analyzed separately. For temperature down-jumps, the glass exhibits a typical stretched exponential kinetic behavior with the non-exponentiality parameter β < 1, whereas up-jumps show a compressed exponential behavior (β > 1). We analyzed these datasets using the non-exponential and non-linear Tool–Narayanaswamy–Moynihan (TNM) model, aiming to provide a comprehensive description of the primary or α-relaxation of the glass. This model described both up- and down-jump datasets using a single value of β ≤ 1. However, the standard TNM model exhibited a progressively reduced capacity to describe the data for larger temperature jumps, which is likely a manifestation of the temperature dependence of the non-exponentiality or non-linearity of the relaxation process. We hypothesize that the compressed exponential relaxation kinetics observed for temperature up-jumps stems from a nucleation-growth-percolation-based evolution on the dynamically mobile regions within the structure, leading to a self-acceleration of the dynamics. On the other hand, temperature down-jumps result in self-retardation, as the slow-relaxing denser regions percolate in the structure to give rise to a stretched exponential behavior. [ABSTRACT FROM AUTHOR]

Two clinical cases involving the fracture of a natural tooth and one of a ceramic crown are presented and discussed based on fractography principles. In the first case, a patient reported intense pain in a sound third molar where a longitudinal fracture was identified, and the tooth was extracted. In the second case, a posterior rehabilitation using a lithium silicate ceramic crown was carried out, and the patient returned after 1 year with a fractured piece of the crown. Both were analyzed under microscopy to identify the origins of fractures and their causes. The fractures were critically analyzed so that relevant information could be generated from the laboratory to the clinic. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the fracture-behavior of monolithic crowns made of lithium disilicate (IPS e.max CAD, Ivoclar Vivadent; IniBal LiSi Block, GC Dental) and zirconia-reinforced lithium silicate (Celtra Duo, DeguDent; VITA Zahnfabrik) materials before and aKer cyclic faBgue aging. Materials and Methods: Four groups (n = 22/group) of CAD/CAM fabricated upper incisor crowns were produced. All crowns were luted on metal dies with an adhesive dualcure resin cement (G-CEM LinkForce, GC Dental). Half of the crowns in each group (n = 11) were staBcally loaded unBl fracture, without aging. The remaining crowns were subjected to cyclic faBgue aging for 120,000 cycles (Fmax = 220 N) and then loaded staBcally unBl fracture. The fractured models were then visually examined. Scanning electron microsopy (SEM) and energy-dispersive spectroscopy (EDS) were used to evaluate the microstructure of CAD/CAM ceramic materials. The data were staBsBcally analyzed with two-way ANOVA followed by the Tukey HSD test (a = .05). Results: Before cyclic aging, there was no staBsBcally significant difference in load-bearing capacity among the four groups (P = .371). AKer cyclic aging, load-bearing capacity significantly decreased for all groups (P = .000). While the e.max CAD blocks had significantly higher load-bearing capacity (1061 ± 94 N) than both monolithic ceramic crowns (load-bearing capaciBes of the groups) (P < .05), no significant difference was obtained with the IniBal LiSi Block group (920 ± 140 N) (P = .061). Conclusions: The mechanical performance of monolithic ceramic crowns fabricated from lithium disilicate was befer than zirconia-reinforced lithium silicate aKer cyclic faBgue aging. [ABSTRACT FROM AUTHOR]

A novel CaO–Al 2 O 3 –SiO 2 –Li 2 O (CASL) glass was developed for bonding yttria–stabilized zirconia ceramics (YSZ). The CASL glass possessed a coefficient of thermal expansion (CTE) that matched with YSZ and exhibited outstanding wettability on the surface of YSZ substrate. During the bonding process, mutual dissolution and diffusion between YSZ and CASL glass took place, which ensured good interface bonding. Furthermore, the rapid cooling speed led to a completely amorphous seam, which allowed the CTE of the seam to correspond with that of the original glass. The optimal flexural strength of YSZ/YSZ joints could reach more than 90 % of that of the YSZ. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to evaluate the effect of etching protocols on bond strength, surface roughness, and mechanical properties of a zirconia-reinforced lithium silicate (ZLS) CAD/CAM-ceramic. In total, 100 bars (ISO 6872), 75 plaques, and 25 cubes were cut from ZLS blocks(Vita Suprinity®). The surfaces were standardized, crystallized and divided into five groups: 1. control (no/treatment-C), 2. 5%-Hydrofluoric-acid (HF)/20 s (HF5%20s), 3.HF5%60s, 4.HF10%20s, and 5.HF10%60s. Flexural strength (FS) (three-point bending test, 1 mm/min), roughness (Pa), and micro-shear bond-strength (µSBS) tests were performed. The data were statistically analyzed with one-way ANOVA, Tukey's test (p ˂ 0.05) and Weibull (FS data). C showed higher Pa (1.176 ± 0.370 µm) than HF10%60s (0.627 ± 0.236 µm) and all other groups. Groups C and 20 s showed the most irregular surface patterns. The FS results were not influenced by etching protocols, while the Weibull modulus was, with the 5%HF groups being the most reliable (m: 5.63/6.70), while C and HF10%60s (m: 2.78/2.73) were the least reliable. All fractures originated from surface defects on the treated side of specimens. The 5%HF groups showed higher µSBS (20 s: 21.35 ± 4.70 MPa; 60 s: 23.50 ± 4.27 MPa) than the 10%HF groups (20 s: 14.51 ± 2.47 MPa; 60 s: 16.54 ± 3.12 MPa) and C (6.46 ± 2.71 MPa). The most prevalent failure pattern was "mixed" for etched groups, and "adhesive" for C. Etching protocols affect the evaluated properties by roughening materials' surface and, in some cases, regularizing surface defects. The best overall outcomes were achieved when applying 5%HF. [ABSTRACT FROM AUTHOR]

Pursuing improved electrode materials is essential for addressing the challenges associated with large-scale Li-ion battery applications. Specifically, silicon oxide (SiOx) has emerged as a promising alternative to graphite anodes, despite issues related to volume expansion and rapid capacity degradation. In this study, we synthesized carbon-coated SiOx using diatom biomass derived from artificially cultured diatoms. However, the inherent carbon content from diatoms poses a significant challenge for the electrochemical performance of diatom-based anodes in large-scale applications. Subsequently, we conducted further research and demonstrated excellent performance with a carbon content of 33 wt.% as anodes. Additionally, real-time characterization of the carbonization process was achieved using thermogravimetry coupled with infrared spectroscopy and gas chromatography mass spectrometry (TG-FTIR-GCMS), revealing the emission of CO and C3O2 during carbonization. Furthermore, electrochemical tests of the processed diatom and carbon (PD@C) anode exhibited outstanding rate capability (~500 mAh g−1 at 2 A g−1), high initial Coulomb efficiency (76.95%), and a DLi+ diffusion rate of 1.03 × 10−12 cm2 s−1. Moreover, structural characterization techniques such as HRTEM-SAED were employed, along with DFT calculations, to demonstrate that the lithium storage process involves not only reversible transport in Li2Si2O5 and Li22Si5, but also physical adsorption between the PD and C layers. Exploring the integration of diatom frustules with the intrinsic carbon content in the fabrication of battery anodes may contribute to a deeper understanding of the mechanisms behind their successful application. [ABSTRACT FROM AUTHOR]

The harnessing and utilization of mechanical energy through frictional route have emerged as a promising avenue for advancing clean energy initiatives. Triboelectric charges are generated on the surface of two different materials during friction. These charges are similar to photocatalytic charges and can be utilized for dye degradation by a process called tribocatalysis. In this study, it was found that lithium borate bismuth tungstate (0.7 L i 2 B 4 O 7 − 0.3 B i 2 W O 6) nanocrystal glass-ceramics synthesized by melt-quench technique exhibit excellent tribocatalytic dye degradation performance by harvesting friction energy. X-ray diffraction technique, Raman Spectroscopy and Transmission Electron Microscopy (TEM) was performed to examine the structure, phase, and microstructure of the prepared samples. The maximum tribocatalytic decomposition of Methylene Blue (MB) dye observed was 56 % for as-quenched sample (AQ) and 74 % for heat-treated sample (HT) after 10 h of mechanical stirring at 700 rpm and for Rhodamine B (RhB) dye the degradation achieved was 34 % and 64 % in 8 h for AQ and HT respectively. Due to their superior dye decomposition capabilities, glass-ceramic crystals hold significant promise for harnessing mechanical energy through friction in wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of two different lasers and their use in combination with hydrofluoric acid (HF) etching on the surface roughness of zirconia-reinforced lithium silicate (ZLS) ceramics and their shear bond strength (SBS) to composite resin. Materials and Methods: The five study groups were as follows: (1) Group H = HF etching; (2) Group N = Nd:YAG (neodymium: yttrium-aluminum-garnet) laser; (3) Group NH = Nd:YAG laser + HF gel; (4) Group E = Er:YAG (erbium: yttrium-aluminum-garnet) laser; and (5) Group EH = Er:YAG laser + HF gel. Surface roughness was assessed using a noncontact profilometer, and SBS tests were conducted with a universal testing machine. Results: The mean SBS values were 16.23 ± 1.77 MPa for Group H, 17.1 ± 1.65 MPa for Group N, 16.65 ± 1.11 MPa for Group NH, 8.08 ± 1.12 MPa for Group E, and 11.58 ± 0.82 MPa for Group EH. There were significant differences between groups E and EH (P < .001) but no significant differences (P > .05) among the other groups. Conclusions: Clinicians may prefer Nd:YAG laser or the combination of Nd:YAG and HF to intraorally repair fractured areas. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the performance of fully crystallized zirconia-reinforced lithium silicate (Celtra Duo, ZLS-CD), partially crystallized zirconia-reinforced lithium silicate (Vita Suprinity, ZLS-VS), and partially sintered lithium disilicate-based (IPS e.max CAD, LD) glass-ceramics submitted to polishing, glazing, or no surface treatment after aging. Material and Methods: Samples of each glass-ceramic material were subjected to polishing with rubber cups (POL), glazing (GL), or no treatment (control: unpolished) and afterward aged with 18,000 thermal cycles (5°C to 55°C). The average roughness, 2D and 3D morphology, contact angle, multispecies biofilm formation (Streptococcus mutans and Candida albicans), and mechanical strength were evaluated with atomic force microscopy (AFM, n = 5), sessile-drop goniometry (n = 5), spectrophotometry (n = 5), and the flexural strength test (n = 10), respectively. Data were analyzed using two-way ANOVA and Tukey test (a = 5%). Results: POL produced lower surface roughness than GL, and ZLS-CD presented higher roughness than LD (P < .05). Surfaces without polishing displayed higher roughness than the POL group (P < .001), greater contact angle (P < .001), and significant morphologic changes, regardless of the glassceramic material. Irrespective of the treatment, the contact angle was higher in the ZLS-CD group, and regardless of the material, there was higher biofilm formation and lower flexural strength of the unpolished compared to the POL or GL ceramics. Conclusions: POL promoted lower roughness and minor morphologic surface alterations, but biofilm formation and flexural strength were similar to the GL group. In general, ZLSCD and ZLS-VS showed more similar behavior than LD, which makes ZLS glass-ceramic a good option for indirect restorations. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of cavity tapering on marginal and internal adaptation of endocrowns fabricated from two different ceramic materials. Materials and Methods: Two mandibular molar model teeth were prepared with two different cavity tapers (5 and 10 degrees). A total of 40 endocrowns (four groups of 10 each) were milled using lithium disilicate and zirconia-reinforced lithium silicate ceramics for each cavity taper. The marginal and internal adaptation of endocrowns were measured by a stereomicroscope (×30) at 18 different points. The data were statistically analyzed using independent t test (P < .05). Results: A statistically significant difference was shown among the tested groups at 10 degrees of taper (P < .001). At 5 degrees of taper, the difference was insignificant. The greatest internal gap was observed at the pulpal floor in all tested groups. Conclusion: All materials had clinically acceptable internal and marginal gaps; however, lithium disilicate ceramic had significantly better adaptation at 10 degrees of taper. [ABSTRACT FROM AUTHOR]

LAS glass-ceramics stimulate considerable attention in academic and industrial fields due to exceptional properties, such as low thermal expansion coefficient, transparency or superior mechanical strength. We report here an experimental investigation of LAS structure and microstructure using conventional techniques as XRD or S/TEM, but also an innovative technique based on electron diffraction mapping. The later gives a topography of the sample and a clear picture of the distribution between the glass and the spodumene particles. All the data converge towards a model of hard spheres where 75 % of the volume is composed of spheroid particles and 25 % of the remaining volume is composed of glass, which is present in the inter-particle interstices. These findings provide a new knowledge about the LAS system and may offer useful guidance for other researchers in ceramic community. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to determine the effect of different surface conditioning techniques on the bond strength between zirconia-reinforced lithium silicate (ZLS) ceramics and resin cement. Materials and Methods: Fifty samples of ZLS ceramic were used and allotted into five groups with 10 samples per group based on the type of surface conditioning technique. The ceramic specimens were crystallized and embedded into acrylic resin. The five groups were group 1 (negative control-without surface treatment); group 2 (10% hydrofluoric [HF] acid + silanization); group 3 (10% HF acid only); group 4 (self-etching ceramic primer [SECP]); and group 5 (experimental laboratory sealing of the conditioned surface). Resin cylinders were bonded using self-adhesive resin cement and were subjected to thermocycling after 24 h storage. The shear bond strength was tested with a universal testing machine. Statistical Analysis Used: One-way ANOVA was used for comparing five groups (P < 0.05 was considered significant). Results: Group 4 showed the highest mean bond strength value (23.4 MPa ± 2.21 MPa). A statistically significant difference was noted between group 4 and all the other groups tested in the study (P < 0.05). Conclusion: It can be concluded that the SECP can be considered an alternative to the conventional protocol of HF acid and silane application for the surface conditioning of ZLS ceramic. [ABSTRACT FROM AUTHOR]

The transparent glass ceramic Li 2 O–Al 2 O 3 –SiO 2 (LAS) was successfully prepared through a melting method. The impact of ZnO substitution for Li 2 O on the crystallization and properties of LAS glass ceramics was investigated. The results revealed that with the increase in ZnO substitution from 0% to 4%, the Q4 structural units in the base glass increased, reinforcing the integrity of the glass network structure. This led to an elevation in the glass transition temperature (from 533.5°C to 545.7°C), crystallization temperature (from 728.6°C to 832.3°C), and Vickers hardness (from 5.98 to 6.44 GPa). Additionally, the primary crystalline phases in the glass ceramics transformed from Li 2 Si 2 O 5 and LiAlSi 4 O 10 to cristobalite, and the multiphase crystalline structure transitioned to a single phase with a spherical morphology of the crystalline grains. The discussion delved into the size distribution of crystals in the glass ceramics, revealing that the increase in ZnO content refined the size and homogenized the distribution of the cristobalite crystals. Glass ceramics with 0% and 4% ZnO substitution, nucleated at 570°C for 4 h and crystallized at 700°C for 2 h, yielded lithium disilicate glass ceramic and cristobalite glass ceramic, respectively, with maximum transmittances (at 550 nm) of 86.92% and 88.79%. The study indicated that the type and size of precipitated crystalline phases significantly influenced the whiteness of the glass ceramics, with minimal impact on other color parameters. Moreover, the presence of fine grains in the glass ceramics, compared with the base glass, imparted a higher hardness. The addition of ZnO exhibited an increasing trend in the toughness of the glass ceramics. At a ZnO substitution of 4% and a crystallization temperature of 700°C, the glass ceramic with cristobalite as the crystalline phase demonstrated optimal comprehensive performance. [ABSTRACT FROM AUTHOR]

This study synthesizes silicon (Si) powders with lithium silicates including lithium orthosilicate (Li4SiO4), lithium metasilicate (Li2SiO3), and lithium disilicate (Li2Si2O5), creating a composite structure of crystalline Si within a LixSiyOz matrix through the lithiothermic reduction reaction (LTRR) process. The reduction of Li‐ion consumption of the anode is investigated by 1) initial solid electrolyte interphase (SEI) layer formation, 2) SEI layer formation in response to Si expansion‐induced damage, 3) trapping of Li ions at Si defects, and 4) side reactions during initial charge and discharge cycles. Si/LixSiyOz electrode exhibits a specific capacity of 1522.2 mAh g−1 and an initial coulombic efficiency of 83.5%. The effect of the calendering process is observed, and a pressurization condition of 5000 kgf cm−2 or less is set, and the ICE is improved to 93.4%–96%. Si/LixSiyOz electrodes outperform pure crystalline Si electrodes in specific capacity (7.3%), ICE (42%), and retention characteristics (17%). The integration of the LixSiyOz matrix into Si anodes enhances Li‐ion transport and partially suppresses Si expansion. Additionally, the Si/LixSiyOz electrode exhibits superior rate capability in the 0.2–1.6 A g−1 range. [ABSTRACT FROM AUTHOR]

This in-vitro study aimed to evaluate the fracture strength (FS; N) of composite, feldspathic, and glass–ceramic computer-aided design/computer-aided manufacturing (CAD/CAM) endocrowns after thermomechanical aging. Seventy non-carious human molars were randomly divided into seven groups, according to the CAD/CAM material used for endocrown fabrication. Intact molars without cavity preparations were used as control (n = 10). Following endodontic treatment, standardized endocrown cavities were prepared and endocrowns were fabricated using composite (Cerasmart270, CS and Grandio Blocs, GB), fired and milled zirconia-reinforced lithium silicate (Celtra Duo, CD), leucite-reinforced feldspar ceramic (LRF Initial, LRF), and feldspathic (Cerec Blocks, CE) materials which were luted with universal adhesive (Futurabond U; Voco) and dual-cure resin cement (Bifix QM). Following thermocycling for 20,000 cycles and 480,000 load cycles in a chewing simulator (CS-4.2, SD Mechatronik), FS was evaluated (Instron). Data were analyzed with one-way ANOVA and post hoc Tukey's tests (p < 0.05). FS was significantly influenced by the tested material (p = 0.00). CS had the highest FS, which was not significantly different from intact molars and fired CD (p > 0.05). There were no significant differences in FS between LRF, GB, and CD, which were significantly higher than CE. Most of the failure modes of CS, CD, and GB were repairable, whereas those of CE were irreparable. All the tested materials withstood clinically relevant axial forces. Composite endocrowns exhibited more favorable fracture pattern, whereas feldspathic and leucite-reinforced feldspar ceramic endocrowns exhibited mostly irreparable fractures. [ABSTRACT FROM AUTHOR]

Influences of various doping elements on the corrosion behavior and possible failure mechanism of aluminum nitride ceramic in lithium had been investigated using X-ray diffraction and scanning electron microscope techniques. The results showed that different doping element could produce obvious effects on the corrosion behavior of aluminum nitride. In comparison with yttrium doping, better corrosion resistance in lithium could be achieved in zirconia doped aluminum nitride. This was attributed to a certain degree of compatibility of both the doped zirconium and its related compounds with lithium. Based on these observations, a corrosion resistance mechanism model was proposed, in which lithium was supposed to be hindered from diffusing into aluminum nitride by a network structure with the impurities, ie. ZrN and Al 2.85 N 0.5 O 3.5 , as the nodes. The corrosion resistance could also be improved effectively by fine and homogeneous grains due to the influences of grain sizes on the node number in network structure. Further studies on the corrosion behavior in embedded liquid lithium implied that the severity of corrosion had close relations with the sample surface quality. [ABSTRACT FROM AUTHOR]

Background: In everyday dentistry, monolithic single crowns can be cemented with self-adhesive resin cements. The aim of this in vitro study was to evaluate how the marginal adaptation of full monolithic zirconia-reinforced lithium silicate (ZLS) single crowns is influenced by three different self-adhesive resin cements. Methods: Forty-five typodont teeth fully prepared for full monolithic crowns were divided into three groups (fifteen each) for the use of three different self-adhesive resin cements. A fourth control group (Temp-bond) was created by taking five teeth from each group before cementation with self-adhesive resin cements. All forty-five abutments were scanned using a Primescan intra-oral scanner (IOS), followed by computer-aided design (CAD) and computer-aided manufacturing (CAM) of zirconia-reinforced lithium silicate (ZLS) full crowns using a four-axis machine. Initially, the crowns of the control group were fixed to the abutments using Temp-bond, and the marginal gap was evaluated using a scanning electron microscope (SEM). After removing the control group crowns from the abutments, fifteen crowns in each group were cemented using a different self-adhesive resin cement and observed under SEM for evaluation of the marginal gap. A Kolmogorov–Smirnov test was performed, indicating no normal distribution (p < 0.05), followed by Mann–Whitney tests (α = 0.05). Results: The total mean marginal gap of the temp-bond control group was significantly lower compared to all three groups of self-adhesive resin cement (p < 0.0005). The total mean marginal gap of the G-cem ONE group was significantly lower compared to the TheraCem group (p < 0.026) and RelyX U200 group (p < 0.008). The total mean marginal gap of the TheraCem group was significantly higher than the G-cem ONE group (p < 0.026) but showed no significant difference with the RelyX U200 group (p > 0.110). Conclusions: All four groups showed a clinically acceptable marginal gap (<120 microns). Although all three groups of self-adhesive resin cement showed a significant increase in the marginal gap compared to the temp-bond control group, they were within the limits of clinical acceptability. Regarding the marginal gap, in everyday dentistry, it is acceptable to use all three self-adhesive resin cements, although the G-cem ONE group exhibited the lowest marginal gap for ZLS single crowns. [ABSTRACT FROM AUTHOR]

This study presents the fabrication of an all‐solid‐state lithium‐ion battery using lithium manganese oxide (LiMn2O4; LMO) as the cathode, graphite (C), and carbon‐coated magnesium (MgC) as the anode, along with a silicate‐based solid electrolyte. To assess the charge/discharge mechanism, three polymeric membranes with varying weight percentages (5%, 30%, and 50%) of magnesium silicate are produced through battery‐cloth deposition (BCD) for use as the solid electrolyte. The findings reveal that enhancing the magnesium silicate content in the solid electrolyte (particularly at 50%) results in an increased specific capacity of the battery. The MgC anode exhibits a peak capacity of approximately 780 mAh/g during the third cycle, maintaining capacity retention of 100% over 26 cycles, addressing the issues of low specific capacity and self‐discharge in the solid‐state Li‐ion battery. Nevertheless, prolonged charge/discharge testing leads to an escalation in the surface roughness and porosity of the carbon coating on the MgC anode, resulting in a decline in capacity. These results demonstrate that the LMO‐BCD‐MgC battery system proposed in this study is a secure, eco‐friendly, and cost‐effective option with potential applications in energy storage. [ABSTRACT FROM AUTHOR]

(1) Background: The presence of various dental ceramic materials with different chemical compositions complicates clinicians' decision making, especially in cases with a highly acidic environment appearing in patients suffering from gastroesophageal reflux disease or other eating disorders. Thermal alterations in the oral cavity can also affect surface structure and roughness, resulting in variations in both degradation mechanisms and/or bacteria adhesion. The aim of the present in vitro study was to evaluate the effect of thermal cycling and exposure to simulated gastric acid on the surface roughness of different ceramics; (2) Methods: Five groups of different ceramics were utilized, and twenty specimens were fabricated for each group. Specimens were either thermocycled for 10,000 cycles in distilled water or immersed in simulated gastric acid for 91 h. The evaluation of surface roughness was performed with optical profilometry, while scanning electron microscopy, X-ray diffraction analysis and inductively coupled plasma atomic emission spectroscopy were also performed; (4) Conclusions: Based on the combination of the surface roughness profile and structural integrity, zirconia specimens presented the smallest changes after immersion in simulated gastric acid followed by lithium disilicate materials. Zirconia-reinforced lithium silicate ceramic presented the most notable changes in microstructure and roughness after both treatments. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of restorative materials with or without resin content, modeled on zirconia and titanium abutment materials, on the stress distribution on the alveolar bone, implant, and prosthetic crowns with a 3D finite element stress analysis. Material and Methods: Titanium and zirconia abutments were combined with three implant‐supported crown materials (polymer infiltrated hybrid ceramic (PICN), lithium disilicate (LD), and zirconia‐reinforced lithium silicate (ZLS)) to create six experimental groups. The 40 × 30 × 20 mm alveolar bone, 3.75 × 10 mm implant, esthetic abutment, and maxillary first premolar crown bonded over the abutment were the components of the finite element models. On the lingual cusp of the crown, the 150 N occlusal loading was applied in the buccolingual direction at a 30° angle. Equivalent von Mises stress and maximum and minimum principal stresses were used for both the qualitative and quantitative evaluation of the stress distribution of the created models. Results: The von Mises stress in implant and abutment did not differ according to the crown materials. The use of a zirconia abutment resulted in higher von Mises stress values in the abutment but lower stress values in the implant. The highest stress values were obtained in ZLS (196.65 MPa) and LD (194.05 MPa) crowns. The use of titanium abutments, regardless of crown materials, resulted in higher von Mises stress values in restorative crowns than in zirconia abutments. The principal stress values in alveolar bone showed similar distribution and concentration in all models. Conclusions: Changes in crown material did not affect stress distribution in the implant and peripheral bone. However, the zirconia esthetic abutment resulted in a lower stress concentration on the implant. [ABSTRACT FROM AUTHOR]

Until quite recently, in almost all papers on crystal nucleation in glass-forming substances, it was assumed that nucleation proceeds in a completely relaxed supercooled liquid and, hence, at constant values of the critical parameters determining the nucleation rate for any given set of temperature, pressure, and composition. Here, we analyze the validity of this hypothesis for a model system by studying nucleation in a lithium silicate glass treated for very long times (up to 250 days) in deeply supercooled states, reaching 60 K below the laboratory glass transition temperature, Tg. At all temperatures in the considered range, T < Tg, we observed an enormous difference between the experimental number of nucleated crystals, N(t), and its theoretically expected value computed by assuming the metastable state of the relaxing glass has been reached. Analyzing the origin of this discrepancy, we confirmed that the key parameters determining the nucleation rates change with time as a result of the glass relaxation process. Finally, we demonstrate that, for temperatures below 683 K, this particular glass almost fully crystallizes prior to reaching the ultimate steady-state nucleation regime (e.g., at 663 K, it would take 176 years for the glass to reach 99% crystallization, while 2600 years would be needed for complete relaxation). This comprehensive study proves that structural relaxation strongly affects crystal nucleation in deeply supercooled states at temperatures well below Tg; hence, this phenomenon has to be accounted for in any crystal nucleation model. [ABSTRACT FROM AUTHOR]

Until quite recently, in almost all papers on crystal nucleation in glass-forming substances, it was assumed that nucleation proceeds in a completely relaxed supercooled liquid and, hence, at constant values of the critical parameters determining the nucleation rate for any given set of temperature, pressure, and composition. Here, we analyze the validity of this hypothesis for a model system by studying nucleation in a lithium silicate glass treated for very long times (up to 250 days) in deeply supercooled states, reaching 60 K below the laboratory glass transition temperature, Tg. At all temperatures in the considered range, T < Tg, we observed an enormous difference between the experimental number of nucleated crystals, N(t), and its theoretically expected value computed by assuming the metastable state of the relaxing glass has been reached. Analyzing the origin of this discrepancy, we confirmed that the key parameters determining the nucleation rates change with time as a result of the glass relaxation process. Finally, we demonstrate that, for temperatures below 683 K, this particular glass almost fully crystallizes prior to reaching the ultimate steady-state nucleation regime (e.g., at 663 K, it would take 176 years for the glass to reach 99% crystallization, while 2600 years would be needed for complete relaxation). This comprehensive study proves that structural relaxation strongly affects crystal nucleation in deeply supercooled states at temperatures well below Tg; hence, this phenomenon has to be accounted for in any crystal nucleation model. [ABSTRACT FROM AUTHOR]

Silicon oxide (SiOx) anode materials have gained significant attention in lithium-ion batteries due to their high theoretical specific capacity (above 1965 mAh g−1), relatively stable cycling performance, and lower production costs. However, SiOx anode materials tend to form a solid electrolyte interphase (SEI) film and generate inert substances like Li2O and Li4SiO4 during the initial charge and discharge processes, leading to the consumption of active lithium ions and low initial coulombic efficiency. To address these issues effectively, prelithiation of SiOx anode materials is explored in this study. A lithium powder suspension is prepared by dispersing lithium powder and carbon nanotubes (CNTs) in the electrolyte, served as the prelithiation agent. The SiO/G@C@A anode material is then prelithiated with this agent. The lithium powder suspension prelithiation agent enables effective prelithiation of the anode material. The SiO@C@A-1 anode exhibits improved electrochemical performances. At a current density of 0.1 A g−1, the initial specific capacity reaches 981.3 mAh g−1 with an initial coulombic efficiency of 95.65%, which is approximately 25% higher than that of the untreated sample. After 100 cycles and at a current density of 0.5 A g−1, the prelithiated sample retains a discharge specific capacity of 648 mAh g−1, with a capacity retention rate of 83.27%, around 10% higher than that of the untreated sample, demonstrating excellent cycling performances. [ABSTRACT FROM AUTHOR]

A novel (Li,Cr)–ZrSiO 4 jade green ceramic pigment was prepared using LiF as the mineralizer and synergistically enhanced charge-compensator. The effects of Cr/Si mole ratio on the synthesis and coloration of the pigment and the coloring mechanism were investigated via XRD, SEM, TEM, XPS, EPR, NMR, UV–Vis–NIR and CIELAB colorimetry. The results demonstrate that the charge-compensator promotes the synthesis of ZrSiO 4 , and more Cr enters into the zircon lattice. When the n(Cr)/n(Si) is 0.2, the pigments exhibit a jade green hue (L* = 75.74, a* = -7.37, b* = 5.18). The band of the (Li,Cr)–ZrSiO 4 pigments in the visible light region shifts towards positive wavelength (535 nm), which is closer to the center of the green light region. The novel pigments have excellent coloring performance stability while in a base glaze synthesized at 1200 °C and near-infrared reflectance in the range of 700–2500 nm. The co-doping of lithium balances bonding, thereby improving near-infrared performance, which shows broad development prospects in the field of ceramic applications and energy saving. [ABSTRACT FROM AUTHOR]

Zirconia-reinforced lithium silicate (ZLS) is utilized as a material for prosthetic tooth crowns, offering enhanced strength compared to other dental glass-ceramics. In this study, we investigate a commercial ZLS material, provided in a fully crystallized form. We examine the effects of an optional post-processing heat treatment on micro-contact damage using controlled indentation tests simulating the primary modes of contact during chewing: axial and sliding. Our findings indicate that the heat treatment does not affect mechanical properties such as the elastic modulus, hardness and indentation fracture toughness. However, it does enhance the resistance to contact damage by fracture and chipping in both axial and sliding modes, as well as the resistance to crack initiation measured from sliding tests. This improvement is attributed to the refinement of the flaw population achieved through the heat treatment. The results are analysed using principles of contact and fracture mechanics theory, discussing their significance in prosthetic dentistry. [ABSTRACT FROM AUTHOR]

Lithium silicate-based glass ceramics have evolved as a paramount restorative material in restorative and prosthetic dentistry, exhibiting outstanding esthetic and mechanical performance. Along with subtractive machining techniques, this material class has conquered the market and satisfied the patients' needs for a long-lasting, excellent, and metal-free alternative for single tooth replacements and even smaller bridgework. Despite the popularity, not much is known about the material chemistry, microstructure and terminal behaviour. This article combines a set of own experimental data with extensive review of data from literature and other resources. Starting at manufacturer claims on unique selling propositions, properties, and microstructural features, the aim is to validate those claims, based on glass science. Deep knowledge is mandatory for understanding the microstructure evolution during the glass ceramic process. Fundamental glass characteristics have been addressed, leading to formation of time-temperature-transformation (TTT) diagrams, which are the basis for kinetic description of the glass ceramic process. Nucleation and crystallization kinetics are outlined in this contribution as well as analytical methods to describe the crystalline fraction and composition qualitatively and quantitatively. In relation to microstructure, the mechanical performance of lithium silicate-based glass ceramics has been investigated with focus on fracture strength versus fracture toughness as relevant clinical predictors. Fracture toughness has been found to be a stronger link to initially outlined manufacturer claims, and to more precisely match ISO recommendations for clinical indications. [ABSTRACT FROM AUTHOR]

The triboelectric effect has recently showcased significant potential in environmental remediation applications. It has been employed to initiate various catalytic reactions through the utilization of minimal mechanical energy. In this context, the present study focuses on the tribocatalytic activity of LiNbO 3 powder prepared via solid-state reaction process. From the study, it was found that ∼92 % of Rhodamine B (RB) dye was degraded in 15 h of mechanical stirring. The results showed that there is significant influence of each parameter in the tribocatalysis process. The current study systematically explored the connection between various affecting parameters and the tribocatalysis mechanism by using LiNbO 3 ceramic whereby laying a robust foundation for the advancement of tribocatalysis process. [ABSTRACT FROM AUTHOR]

This study aimed to compare the impact of CAD/CAM closed systems and open systems on the marginal gap of monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns, as both systems are used in everyday dentistry, both chair-side and laboratory. For the closed system, 20 plastic teeth were scanned by a Primescan intra-oral scanner (IOS), and for the open system, the same number of plastic teeth were scanned by Trios 4 IOS. For the closed system, CEREC software was used, and for the open system, EXOCAD software was used. All 40 ZLS crowns were grinded by the same four-axis machine and cemented with Temp-bond, followed by self-adhesive resin cement. For each type of cement, an evaluation of the marginal gap was conducted by scanning electron microscopy (SEM). Before comparisons between the groups, a Kolmogorov–Smirnov test was performed on the study variables showing a normal distribution (p > 0.05). Independent T tests (α = 0.05) and paired-sample T tests (α = 0.05) were used. The independent T test found no significant mean marginal gap differences in the zirconia-reinforced lithium silicate crowns bonded with Temp-bond and scanned by Primescan (28.09 μm ± 3.06) compared to Trios 4 (28.94 μm ± 3.30) (p = 0.401), and there was no significant mean marginal gap differences in zirconia-reinforced lithium silicate crowns bonded with self-adhesive resin cement (Gcem ONE) and scanned by Primescan (46.70 μm ± 3.80) compared to Trios 4 (47.79 μm ± 2.59) (p = 0.295). Paired-sample T tests showed significantly higher mean marginal gaps with Gcem ONE compared to Temp-bond for the total mean marginal gap when scanning with Primescan (p = 0.0005) or Trios 4 (p = 0.0005). In everyday dentistry, both closed systems (Primescan with Cerec) and open systems (Trios 4 with Exocad) can be used to achieve an acceptable (<120 µm) marginal gap for ZLS CELTRA® DUO single crowns. There is a significant difference between cementation with Temp-bond and Gcem ONE self-adhesive resin cement (p < 0.05). [ABSTRACT FROM AUTHOR]

Excellent spinel microwave dielectric ceramics (1- x)Zn 2 TiO 4 - x Li 2 MgTi 3 O 8 (ZTLMT x , x = 1/3 and 2/3) were prepared at relatively low densification temperatures of 1100 °C and 1080 °C, respectively. A disordered cubic phase with space group Fd -3 m was formed at x = 1/3, whereas an ordered cubic phase with space group P 4 3 32 was formed at x = 2/3. The ceramics at x = 1/3 and 2/3 exhibited promising microwave dielectric properties of ɛ r = 18.27 and 22.96, Q × f = 91,877 GHz and 75,186 GHz, and τ f = −42.3 ppm/°C and −21.05 ppm/°C, respectively. The large deviation between the experimental ԑ r and theoretical ε th of 1/3 and 2/3 ceramics were 18.3 % and 57 %, respectively, due to the underestimation of the ionic polarizability of Ti4+. The difference in their ɛ r , Q × f , and τ f were discussed by the structure, FWHM of A 1g , lattice energy and bond energy in detail. [ABSTRACT FROM AUTHOR]

Lithium silicate (LS) glass ceramic with excellent mechanical performance has been used in dental restoration but is seldom used in orthopedics due to its limited bioactivity. Given the osteoconductive features of calcium phosphate-based ceramics, optimizing the P 2 O 5 content to adjust the ratio of CaO to P 2 O 5 may improve the bioactivity of glass ceramics. The effect of P 2 O 5 content on the phase formation, mechanical performance, cell proliferation, cell differentiation and mineralization of glass ceramics were investigated in this study. The results indicated that increasing the content of P 2 O 5 increased the formation temperature of LiAlSi 2 O 6 and provided nucleation sites for Li 2 SiO 3 by forming Li 3 PO 4 which, in turn, promoted the transformation from Li 2 SiO 3 to Li 2 Si 2 O 5. The phase morphology transformed from a lamellar shape to a columnar shape, and then formed an interlocking structure in the specific heat treatment. The phase transformation and formation of Li 3 PO 4 improved cell proliferation, cell differentiation, and mineralization of the glass ceramics. In particular, the glass ceramic with 2.58 mol% P 2 O 5 (LS3) and 4.12 mol% P 2 O 5 (LS4) promoted the expression of alkaline phosphatase (ALP) and achieved the strength requirement of bone. In conclusion, the bioactivity of the glass ceramics was enhanced by increasing the P 2 O 5 content, and the bone-like structure on the surface of the glass ceramic with 4.12 mol% P 2 O 5 may make this material suitable for orthopaedic applications. [ABSTRACT FROM AUTHOR]

To study the influence of the nucleation mechanism in lithium aluminosilicate glass, a composition similar to commercially produced glass was used. The glass-ceramics was obtained as a result of two-stage heat treatment, differing in the nucleation temperature and coinciding in the temperature and time of crystal growth. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) were used to study the formed nanocrystals. It was shown that the change of nucleation temperature in the glass transition interval T g ±15 °C significantly affects the coefficient of thermal expansion, which is due to the formation of a different number of nanocrystals of the general composition Li x Al x Si 1- x O 2 with x = 0.33 with the size less than 50 nm. [ABSTRACT FROM AUTHOR]

Understanding the nucleation mechanism in glass is crucial for the development of new glass-ceramic materials. Herein, we report the structure of a commercially important glass-ceramic ZrO2-doped lithium aluminosilicate system during its initial nucleation stage. We conducted an X-ray multiscale analysis, and this analysis was used to observe the structure from the atomic to the nanometer scale by using diffraction, small-angle scattering, absorption, and anomalous scattering techniques. The inherent phase separation between the Zr-rich and Zr-poor regions in the pristine glass was enhanced by thermal treatment without changing the spatial geometry at the nanoscale. Element-specific pair distribution function analysis using anomalous X-ray scattering data showed the formation of a liquid ZrO2-like local structural motif and edge sharing between the ZrOx polyhedra and (Si/Al)O4 tetrahedra during the initial nucleation stage. Furthermore, the local structure of the Zr4+ ions resembled a cubic or tetragonal ZrO2 crystalline phase and formed after 2 h of annealing the pristine glass. Therefore, the Zr-centric periodic structure formed in the early stage of nucleation was potentially the initial crystal nucleus for the Zr-doped lithium aluminosilicate glass-ceramic. Unlocking the Secrets of ZrO2-Doped Glass-Ceramic Nucleation: This research examines the early changes in the formation of zirconium-doped aluminosilicate glass-ceramic, a material used in many industrial goods. Led by Y. Onodera and Y. Takimoto, the study shows that during the formation process, a liquid-like local structure around a Zr4+ ion (a positively charged particle) and shared structures between ZrOx and (Si/Al)O4 tetrahedra (four-faced geometric shapes) are created. The researchers used various X-ray techniques to perform a detailed structural analysis. This study offers fresh understanding of the structure of formation agents in glasses and could improve our knowledge of the formation process in the early stages of glass-ceramic materials. Future studies could look into how these findings could be used in creating new materials. This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author. The structure of a commercially important glass-ceramic ZrO2-doped lithium aluminosilicate system during its initial nucleation stage was investigated by an X-ray multiscale analysis which enables us to observe the structure from the atomic to the nanometer scale by using diffraction, small-angle scattering, absorption, and anomalous scattering techniques. The combinatorial approach revealed that the formation of edge sharing between the ZrOx polyhedra and (Si/Al)O4 tetrahedra, and that the Zr-centric periodic structure in which the local structure of the Zr4+ ions resembled a cubic or tetragonal ZrO2 crystalline phase was potentially the initial crystal nucleus for the Zr-doped lithium aluminosilicate glass-ceramic. [ABSTRACT FROM AUTHOR]

To address the problem of insufficient temperature and salt resistance of existing polymer viscosity enhancers, we designed an organic–inorganic hybrid composite as a viscosity enhancer for water-based drilling fluids, named LAZ, and it was prepared by combining a water-soluble monomer and lithium magnesium silicate (LMS) using an intercalation polymerization method. The composite LAZ was characterized using Fourier transform infrared spectroscopy, transformed target X-ray diffractometry, scanning electron microscopy, and thermogravimetric analysis. The rheological properties of the composite LAZ were evaluated. The composite LAZ was used as a water-based drilling fluid viscosity enhancer, and the temperature and salt resistance of the drilling fluid were evaluated. The results showed that the composite LAZ presented a complex reticulation structure in an aqueous solution. This reticulation structure intertwined with each other exhibited viscosity-enhancing properties, which can enhance the suspension properties of water-based drilling fluids. The aqueous solution of the composite LAZ has shear dilution properties. As shear rate increases, shear stress becomes larger. The yield stress value of the aqueous solution increases as the composite LAZ's concentration increases. The aqueous solution of the composite LAZ exhibits strong elastic characteristics with weak gel properties. The addition of the composite LAZ to 4% sodium bentonite-based slurry significantly increased the apparent viscosity and dynamic shear of the drilling fluid. The drilling fluids containing the composite LAZ had good temperature resistance at 150 °C and below. The rheological properties of brine drilling fluids containing the composite LAZ changed slightly before and after high-temperature aging at 150 °C. [ABSTRACT FROM AUTHOR]

Background and aims. Dental veneers have become increasingly required among patients, but little is known about the optical properties of veneers obtained from the same ceramic material through different processing techniques. Methods. In this study we compared the translucency and the opalescence parameters of zirconia-reinforced lithium silicate (ZLS) veneers restorations fabricated through CAD/CAM milling and hot-pressing techniques on the upper central incisor. Eighty specimens divided into 8 groups (n=10) were sectioned (Celtra Duo) and heat pressed (Celtra Press) to obtain 0.8 mm thickness. The optical parameters were calculated from the color difference against different backgrounds. Analysis of variance, one way ANOVA and post-hoc multiple comparison tests were used to evaluate and compare the optical properties of the same material, with a significance level of p < 0.05. Results. The processing method had significant effect on optical parameters. Celtra Duo HT proved to be the material with the highest transparency degree. The hotpressing technique led to higher opacity than CAD/CAM milling technique. Conclusions. For a bio-mimetic aesthetic prosthetic restoration, the ceramic materials must have the same translucency and opacity as the real tooth. The results of this study revealed that high translucency ZLS obtained through hot pressing technique was the material of choice, as it fulfilled these requirements. [ABSTRACT FROM AUTHOR]

New generation intumescent coatings apply self-intumescing particles to induce expansion in a controlled manner. Various studies have investigated alkali silicate-based coatings due to their inherent expansion with the release of H 2 O. The presented work investigated the self-intumescing concept of alkali silicates as particles. A thorough study of inorganic alkali silicate particles as potential intumescent ingredients in passive fire protection systems was carried out by applying HSDM, TGA, FTIR, XRD, and SEM. Herein, particles of lithium-, sodium-, and potassium silicates were synthesized with varying silica-to-alkali oxide molar ratios and curing humidity. Subsequently, the hydration chemistry and thermal behavior were examined. The results revealed increased expansion potential with decreasing SiO 2 /M 2 O molar ratio (M = Na, Li, or K) in the range 3.1–7.4 and increasing curing humidity in the range 35, 50, and 90% RH. Previous studies have emphasized the effect of solid-bound H 2 O to induce intumescence. In this study, the influence of the softening of the silicate matrix and H 2 O release is highlighted to allow increased expansion potential. Here, the coupling of thermal analysis with microscopy suggests an intumescence mechanism in the order of 1) initial shrinkage due to loss of free and physical bound H 2 O, 2) sphere formation to minimize surface energy, 3) expansion as a result of H 2 O evolution and viscoelastic melt formation, and 4) second shrinkage due to sintering before 5) melting. The sodium alkali silicate particles with a SiO 2 /M 2 O molar ratio of 3.4 exhibited a timely softening of the silicate matrix from about 155 °C to provide a distinct spherical particle followed by ionic H 2 O evolution. As a result, hereof, hollow, spherical particles with relative solid expansions of up to 550% were obtained and maintained until a second shrinkage at 650 °C with a subsequent melting at 950 °C. In comparison, the imbalance in viscoelastic melt formation and H 2 O release of lithium- and potassium silicate particles resulted in less expansion. Considering the expansion potential and thermal behavior of the alkali silicate particles, it is suggested as a possible, sustainable intumescence ingredient. [ABSTRACT FROM AUTHOR]

The electrochromic (EC) polymer poly (3,4‐(2,2‐dimethylpropylenedioxy)thiophene) (PProDOT‐Me2) is expected to be used in flexible e‐paper displays because of its great optical modulation ability and inherent flexibility. While the EC effect is primarily determined by the anions and cations in the electrolyte, yet suffers from inorganic salt based on monovalent Li+ cations and corresponding anions, such as lithium perchlorate(LiClO4), lithium bis(trifluoromethane sulfonyl) imide (LiTFSI), and lithium trifluoromethane sulfonate (LiTRIF), which may impact the overall EC performance of the EC device caused by insufficient ion doping/de‐doping processes. Herein, the divalent viologen cation‐based ionogel (VGE) is developed to tackle the challenge. Owing to its more anions design, the doping/de‐doping process in the PProDOT‐Me2 is more sufficient, thereby enhancing the optical modulation range (ΔR = 39.4%) of PProDOT‐Me2, compared to monovalent Li+ cation‐based ionogel (ΔR = 13.3%). Meanwhile, the VGE has good interface contact with PProDOT‐Me2 and the flexible electrode, which makes the VGE‐based EC device (V‐ECD) exhibit commendable mechanical stability. To demonstrate the potential application in flexible e‐paper displays, the simple eight‐digit EC display device is assembled from seven V‐ECDs, each of which hasa high switching speed, robust cycling stability, and low operating energy consumption. [ABSTRACT FROM AUTHOR]

The study aimed to assess the marginal, axial, and internal adaptation, as well as the fracture resistance of zirconia-reinforced lithium silicate (ZLS) endocrowns with varying pulpal inlay extensions and marginal geometry. Sixty extracted maxillary first molar teeth were divided into six groups (n = 10) according to pulpal inlay extension and marginal configuration. The first three groups (J2, J3, and J4) utilized prepared teeth for endocrowns without ferrule design and 2 mm, 3 mm, and 4 mm pulpal extensions, respectively. The second three groups (F2, F3, and F4) utilized prepared teeth with 1 mm shoulder margins and 2 mm, 3 mm, and 4 mm pulpal extensions. The endocrowns were fabricated from ZLS blocks using CAD/CAM milling technology. After cementation, the specimens underwent thermal aging for 5000 cycles and were evaluated for marginal adaptation. Using a universal testing machine, the fracture resistance was tested under quasistatic loading (1 mm/min). Two-way ANOVA and the Tukey's post hoc test were employed for data analysis (p ≤ 0.05). The results of this study revealed that endocrowns without ferrule exhibited superior fracture strength than a 1 mm ferrule design p < 0.05, irrespective of the inlay depth. All designs with and without ferrule and all inlay depths showed clinically acceptable marginal and internal fit. The conventional endocrown design without ferrule and 2 mm inlay depth showed the lowest surface gap. The pulpal surface showed the highest discrepancy among all groups compared to the other surfaces. Endocrowns without ferrule are more conservative and have higher fracture strength than 1 mm ferrule designs; extending the inlay depth showed a significant increase in fracture resistance of the 1 mm ferrule design, but not for the conventional design without ferrule and 2 mm inlay depth. All groups exhibited a high auspicious fracture strength value for molar endocrown restorations. [ABSTRACT FROM AUTHOR]

The "in situ electrolyte" displays a concept for electric double‐layer‐ as well as metal‐ion capacitors in which the by‐products formed during carbon synthesis serve directly as electrolyte salt to minimize waste. In this work, the concept is applied for lithium‐ and sodium‐based systems realizing EDLCs containing aqueous, "Water in Salt" (up to 1.8 V) as well as organic (2.4 V) electrolytes. Via the mechanochemical synthesis, carbon materials with surface areas up to 2000 m2 g−1 and an optimal amount of remaining by‐product are designed from the renewable resource lignin. Different cation‐anion combinations are enabled by further modification directly inside the pores creating imide‐based salts which are tracked by synchrotron in situ XRD. By the addition of solvents, the EDLCs show good capacitances up to 21 F g−1 combined with excellent rate performances and stabilities. Moreover, the LiTFSI loaded carbon as positive electrode introduces a new tunable lithium alternative for the pre‐lithiation of Li‐ion capacitors displaying a good rate performance and cyclability. [ABSTRACT FROM AUTHOR]

In food safety implementation, bacterial inactivation is an imperative aspect of hygiene and sanitation. Studies on lithium magnesium silicate (LMS) hydrosol incorporated with slightly acidic electrolyzed water (SAEW) for decontamination of pathogenic bacteria are limited. This present study aimed to investigate the bactericidal efficacy of LMS hydrosol incorporated with SAEW against Escherichia coli. Optimum combination conditions of SAEW, hydrosol concentration, and available chlorine concentration (ACC) were optimized by response surface methodology under the central composite design against the growth of E. coli. The optimum combination conditions of exposure time, hydrosol concentration, and ACC were 9.5 minutes, 1.7%, and 20.5 ppm, respectively. The results showed that the increase in ACC led to inactivation in the survival of E. coli compared with the control (p<0.05). It can be concluded that the best combination percentage between SAEW and hydrosol ranged from 1.5-1.7%, in which E. coli was reduced by 4.50 log10 CFU/mL at an ACC of 9.94 ppm. When increasing the ACC to 14.84 ppm, E. coli was reduced by 4.51 log10 CFU/mL compared with the initial number of bacteria (8.20 log10 CFU/mL) in the control group. The number of bacteria was undetected after increasing ACC to 19.93, 25.15, and 29.88 ppm at 10 min. This study suggests that LMS hydrosol incorporated with SAEW could potentially be used as an effective sanitizer. [ABSTRACT FROM AUTHOR]

The incidence of microbial infections in orthopedic prosthetic surgeries is a perennial problem that increases morbidity and mortality, representing one of the major complications of such medical interventions. The emergence of novel technologies, especially 3D printing, represents a promising avenue of development for reducing the risk of such eventualities. There are already a host of biomaterials, suitable for 3D printing, that are being tested for antimicrobial properties when they are coated with bioactive compounds, such as antibiotics, or combined with hydrogels with antimicrobial and antioxidant properties, such as chitosan and metal nanoparticles, among others. The materials discussed in the context of this paper comprise beta-tricalcium phosphate (β-TCP), biphasic calcium phosphate (BCP), hydroxyapatite, lithium disilicate glass, polyetheretherketone (PEEK), poly(propylene fumarate) (PPF), poly(trimethylene carbonate) (PTMC), and zirconia. While the recent research results are promising, further development is required to address the increasing antibiotic resistance exhibited by several common pathogens, the potential for fungal infections, and the potential toxicity of some metal nanoparticles. Other solutions, like the incorporation of phytochemicals, should also be explored. Incorporating artificial intelligence (AI) in the development of certain orthopedic implants and the potential use of AI against bacterial infections might represent viable solutions to these problems. Finally, there are some legal considerations associated with the use of biomaterials and the widespread use of 3D printing, which must be taken into account. [ABSTRACT FROM AUTHOR]

Lithium is a significant energy metal. This study focuses on the extraction of lithium from lithium-bearing clay minerals utilizing calcination combined with oxalic acid leaching. The relevant important parameters, leaching kinetics analysis, and the lithium extraction mechanism were deeply investigated. The results demonstrate that a high lithium recovery of 91.35% could be achieved under the optimal conditions of calcination temperature of 600 °C, calcination time of 60 min, leaching temperature of 80 °C, leaching time of 180 min, oxalic acid concentration of 1.2 M, and liquid-to-solid ratio of 8:1. According to the shrinkage core model, the leaching kinetics of lithium using oxalic acid followed a chemical reaction-controlled process. XRD, TG, and SEM analysis showed that the kaolinite, boehmite, and diaspore phases in raw ore transformed into corundum, quartz, and muscovite phase in calcination products when the calcination temperature was higher than 600 °C. Moreover, the expansion of the interlayer spacing of minerals during the calcination process could promote the lithium release. During the leaching process, lithium present in the layered silicates was efficiently recovered through ion exchange with the dissociated H+ from oxalic acid. This study could provide a promising guide for lithium extraction from lithium-bearing clay minerals. [ABSTRACT FROM AUTHOR]

Objective: This in vitro study aimed to evaluate the effectiveness of pretreatment with a self-etching primer for bonding aligner attachments to lithium disilicate (LD) and monolithic zirconia (MZ) ceramics. Methods: Forty ceramics, including LD (n=20) and MZ (n=20), were divided into four study groups according to the surface pretreatments: LD specimens pretreated with universal primer (Monobond Plus, MP) after hydrofluoric acid etching (Group 1); MZ ceramics pretreated with MP after sandblasting (Group 2); LD ceramics pretreated with self-etching ceramic primer (Monobond etch & prime, MEP) (Group 3); and MZ ceramics pretreated with MEP after sandblasting (Group 4). The aligner composite (GC Aligner Connect) and universal adhesive (GPremio Bond) were used to prepare the resin attachments. The bond strength was evaluated by micro-shear bond strength (SBS) testing (0.1 mm/min) after thermocycling, and the remnant adhesive was scored according to the resin attachment remnant index (RARI). The SBS data were analyzed using ANOVA and Tukey tests, and the RARI scores were analyzed using the chi-square test. Results: Group 1 had the lowest SBS, and group 2 had the highest SBS. There were significant differences between the groups in terms of bond strength (p<0.05). The RARI scores showed no significant differences, regardless of the pretreatment and ceramic type. Conclusion: The use of a self-etching primer increased the bond strength of resin attachments on LD ceramics. For zirconia ceramics, both ceramic primers are recommended for aligner attachment bonding. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the fracture resistance of monolithic zirconia‐reinforced lithium silicate laminate veneers (LVs) fabricated on various incisal preparation designs. Materials and methods: Sixty maxillary central incisors with various preparation designs were 3D‐printed, 15 each, including preparation for: (1) LV with feathered‐edge design; (2) LV with butt‐joint design; (3) LV with palatal chamfer; and (4) full‐coverage crown. Restorations were then designed and manufactured from zirconia‐reinforced lithium silicate (ZLS) following the contour of a pre‐operation scan. Restorations were bonded to the assigned preparation using resin cement and following the manufacturer's instructions. Specimens were then subjected to 10,000 thermocycles at 5 to 55°C with a dwell time of 30 s. The fracture strength of specimens was then assessed using a universal testing machine at a crosshead speed of 1.0 mm/min. One‐way ANOVA and Bonferroni correction multiple comparisons were used to assess the fracture strength differences between the test groups (α = 0.001). Descriptive fractographic analysis of specimens was carried out with scanning electron microscopy images. Results: Complete coverage crown and LV with palatal chamfer design had the highest fracture resistance values (781.4 ± 151.4 and 618.2 ± 112.6 N, respectively). Single crown and LV with palatal chamfer had no significant difference in fracture strength (p > 05). LV with feathered‐edge and butt‐joint designs provided significantly (p < 05) lower fracture resistance than complete coverage crown and LV with palatal chamfer design. Conclusion: The fracture resistance of chairside milled ZLS veneers was significantly influenced by the incisal preparation designs tested. Within the limitation of this study, when excessive occlusal forces are expected, LV with palatal chamfer display is the most conservative method of fabricating an indirect restoration. [ABSTRACT FROM AUTHOR]

Background: This study compared the influence of crystallization on marginal gap adaptation by using computer-aided design and manufacturing (CAD-CAM) for producing monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns. Methods: A total of 25 plastic teeth were scanned using a Primescan intra-oral scanner (IOS), and ZLS crowns were ground. For each unit (abutment and crown), the marginal gap was evaluated pre crystallization and post crystallization at four regions of interest through the use of a scanning electron microscope (SEM). To compare the marginal gap between the two groups, a Kolmogorov–Smirnov test performed on the study variables indicated a normal distribution (p > 0.05) followed by paired samples T-tests (α = 0.0005). Results: After crystallization, there were significantly higher circumferential marginal gaps (CMGs) for all four surfaces (distal (p = 0.0005), mesial (p = 0.0005), palatal (p = 0.0005), and buccal (p = 0.0005)). The total mean marginal gap (MMG) revealed a significantly higher result for the post-crystallization group (79.82 ± 7.86 μm) compared to the pre-crystallization group (24.25 ± 5.49 μm). Conclusions: The post-crystallization group showed a significantly higher marginal gap compared to the pre-crystallization group in all parameters, but both groups were in the clinically accepted threshold (<120 microns). In terms of the marginal gap, it is arguable whether to carry out post-crystallization for CELTRA® DUO crowns and achieve better mechanical properties but significantly increase the marginal gap. [ABSTRACT FROM AUTHOR]

Hydrofluoric acid (HF) is commonly used as an etchant for the pretreatment of dental computer-aided design/computer-aided manufacturing (CAD-CAM) materials, such as glass-ceramics and resin composites. Despite its effectiveness, the harmful and hazardous nature of HF has raised significant safety concerns. In contrast, ammonium fluoride (AF) is known for its relatively low toxicity but has limited etching capability. This study explored the potential of ammonium hydrogen sulfate (AHS), a low-toxicity and weak acid, to enhance the etching ability of aqueous AF solutions for the bonding pretreatment of CAD-CAM materials. This study investigated five types of aesthetic CAD-CAM materials: lithium disilicate glass, feldspathic porcelain, polymer-infiltrated ceramic networks, resin composites, and zirconia. Seven experimental etchants were prepared by varying the amount of AHS added to aqueous AF solutions, with each etchant used to etch the surfaces of the respective CAD-CAM materials. The treated surfaces were analyzed using scanning electron microscopy and confocal laser scanning microscopy. Additionally, the shear bond strength (SBS) of the CAD-CAM materials treated with a luting agent (resin cement) was evaluated. The results indicated that the AF1/AHS3 (weight ratio AF:AHS = 1:3) etchant had the most substantial etching effect on the surfaces of silica-containing materials (lithium disilicate glass, feldspathic porcelain, polymer-infiltrated ceramic networks, and resin composites) but not on zirconia. The SBS of the materials treated with the AF1/AHS3 etchant was comparable to that of the commercial HF etchant. Hence, an AF/AHS mixed solution could effectively etch silica-containing CAD-CAM materials, thereby enhancing their bonding capabilities. [ABSTRACT FROM AUTHOR]

Advanced ceramic breeder (ACB) pebbles consisting of the two phases Li4SiO4 and Li2TiO3 serve as the EU reference tritium breeding material. In the present study, the phase stability with regard to a lithium-burn-up is investigated. The loss of lithium due to its transmutation will lead to a compositional change of the breeder material. Li4SiO4 and Li2TiO3 will partly be transformed to the lithium-poorer phases Li2SiO3 and Li4Ti5O12, respectively. However, from the phase diagram it is anticipated that only Li2SiO3 will occur as a third phase after a lithium burn-up as the generated Li4Ti5O12 is expected to further react with Li4SiO4 to form again Li2TiO3 and more Li2SiO3. Therefore, the reaction between Li4SiO4 and Li4Ti5O12 and its temperature dependence were investigated in detail and its reaction kinetics were determined. It was found that this diffusion-controlled reaction with an activation energy of 75 kJ/mol (0.78 eV) will slow down at low irradiation temperatures and may not take place at very low temperatures.

Metadynamics (MetaD) is a useful technique to study rare events such as crystallization. It has been only recently applied to study nucleation and crystallization in glass-forming liquids such as silicates, but the optimal set of parameters to drive crystallization and obtain converged free energy surfaces is still unexplored. In this work, we systematically investigated the effects of the simulation conditions to efficiently study the thermodynamics and mechanism of crystallization in highly viscous systems. As a prototype system, we used fused silica, which easily crystallizes to β-cristobalite through MetaD simulations, owing to its simple microstructure. We investigated the influence of the height, width, and bias factor used to define the biasing Gaussian potential, as well as the effects of the temperature and system size on the results. Among these parameters, the bias factor and temperature seem to be most effective in sampling the free energy landscape of melt to crystal transition and reaching convergence more quickly. We also demonstrate that the temperature rescaling from T > Tm is a reliable approach to recover free energy surfaces below Tm, provided that the temperature gap is below 600 K and the configurational space has been properly sampled. Finally, albeit a complete crystallization is hard to achieve with large simulation boxes, these can be reliably and effectively exploited to study the first stages of nucleation. [ABSTRACT FROM AUTHOR]