Search Results (458)

Objective: This study aimed to assess the impact of different adhesive systems on the color stability of composite veneers following their exposure to various common beverages. Materials and Methods: A single layer of commercially available adhesives (4th and 7th generations) and two experimental adhesives based on hydroxyapatite and bioactive glass were applied, followed by composite restoration on incisor typodonts. The typodonts were prepared with depths of 0.3, 0.5, and 0.7 mm at the cervical, middle, and incisal regions, respectively. Samples from each group were immersed in coffee, Cola, and deionized water, and color stability was analyzed on days 1 and 60. One-way and two-way analyses of variance were performed. Results: The interaction between groups and solutions was statistically significant (p = 0.001) across all tooth regions. Coffee and Cola caused significant color changes (p = 0.001). The 4th generation demonstrated better color stability than the 7th generation in the middle and cervical regions (p-values = 0.083 and 0.003, respectively). The findings showed that the bioactive glass-based bonding agent exhibited greater discoloration than the hydroxyapatite-based adhesive (p = 0.001). Conclusions: The composite thicknesses are influenced differently by adhesives with respect to shade matching. Bioactive materials-based adhesives showed more resistance towards color change than commercial adhesives. Full article

Oral mucositis is an inflammatory and ulcerative disease that affects patients undergoing cancer treatment, namely chemotherapy and radiotherapy, significantly compromising their quality of life. Despite its high incidence and clinical impact, current therapeutic options remain limited, reinforcing the need for new treatment approaches. In this context, the Instituto Português de Oncologia do Porto FG, EPE (IPO-Porto) developed an innovative mouthwash containing dexamethasone sodium phosphate (DSP), ascorbic acid, and sodium hyaluronate. In this work the physicochemical stability of this formulation was evaluated to ensure its quality and safety as compounded medicine. Exploratory studies were performed under accelerated aging conditions (40 ± 2 °C), followed by stability studies under real-time conditions (20 ± 2 °C) and refrigeration conditions (4 ± 2 °C), as well as in-use stability studies simulating daily patient handling. At each sampling time, physicochemical characterization was carried out (pH, color, odor, and precipitate formation) as well as the DSP quantification using high-performance liquid chromatography. The acceptable range of 90.0–110.0%, compared to the initial concentration of DSP, was used as the primary stability criterion. Results showed that the formulation remained stable at high temperatures (40 °C), on short exposures times (≤6 h), and for 30 days at 4 °C in closed amber glass bottles. In-use stability studies performed during the 7 days after opening (considering three daily applications) showed that the DSP concentration remained above 90%. The results obtained enabled us to establish a definition of storage conditions and beyond-use recommendations, since they showed that the prepared formulation is stable when stored under refrigeration. Further studies are currently being developed with a view to its clinical use as a compounded mouthwash in a hospital setting for the treatment of oral mucositis. Full article

The objective of this study was to evaluate the impact of the material (plastic or glass) and color (green or colorless) of extra virgin olive oil (EVOO) and virgin olive oil (VOO) bottles on the acquisition of SORS spectra using portable equipment. Sixteen bottles of EVOO and three bottles of VOO were analyzed, including different volumes. A range of similarity indices was calculated between vial-reference (offline measurements) and bottles (online measurements), including R², COS θ, NEAR, and a new index called WSI (Weighted Similarity Index). WSI is calculated from the pondered linear combination of the previous three, and a threshold of >0.95 is established as high similarity. The results showed that plastic bottles, regardless of color and volume, and colorless glass bottles had WSI values > 0.95. In contrast, green glass bottles demonstrated a lower degree of similarity (WSI < 0.95), which impacted the reliability of their spectral fingerprints. A hierarchical cluster analysis (HCA) was performed by locating EVOO bottles according to their material in two clusters. A study of storage under optimal, non-optimal, and commercial conditions showed that both EVOO and VOO maintain highly similar spectral profiles for 10–18 days (WSI > 0.965), even in bottles purchased in supermarkets. These results demonstrate that the SORS technique is suitable for the direct analysis of olive oils in plastic and colorless glass containers, without the need to open the bottles. The SORS technique is a fast, reliable, non-invasive, and non-destructive tool for quality control of olive oil. Full article

This study investigates the sustainable reuse of industrial enamel frit production waste generated during enamel application processes and evaluates its potential from a process-oriented glass-forming and -shaping perspective. Enamel frit waste collected from an industrial production line in Türkiye was subjected to comprehensive characterization, including XRD, XRF, TG/DTA, dilatometry, and CIE Lab* color analysis, with the primary aim of assessing forming compatibility rather than final product performance. Following calcination and controlled fritting, the waste material was processed through mold-based glass-forming experiments using firing schedules derived from thermal analysis. The results reveal pronounced chemical and thermal heterogeneity among enamel frit production wastes, leading to variable melting behavior across samples. Nevertheless, selected waste compositions exhibited sufficient viscous flow for shaping at reduced firing temperatures of approximately 850 °C. This study demonstrates that selected enamel frit production wastes—obtained from industrial enameling processes in slurry, powder, or granular form—can be reshaped into glass forms under controlled low-temperature conditions. The novelty of this study lies in investigating industrial enamel production frit waste as a reusable material within a circular economy framework, specifically focusing on its application in mold-based glass forming for artistic and educational contexts, thereby fostering collaboration between industrial waste management and glass art practice. Full article

Boro-antimonite glasses doped with Eu³⁺ and having the general composition (90-x) Sb₂O₃–xB₂O₃–10Li₂O-0.5Eu₂O₃ (x = 0 to 60 in 10 mol. % increment) were prepared using the melt quenching method. The influence of B₂O₃/Sb₂O₃ substitution on the spectroscopy and photoluminescence of Eu³⁺ ions was analyzed by studying the measured and calculated properties of these glasses. The relative value of a given property was shown to increase or decrease by up to 26% with the addition of up to 60 mol. % B₂O₃, while the number of Eu³⁺ ions per unit volume increased by approximately 32%. Strong emissions were obtained in association with the transitions of Eu³⁺ (⁵D₀→⁷F_j, j = 1–4). A weak, broad emission centered at 450 nm was also detected. This emission is clearly linked to the glass composition. It originates from a potential presence of Eu²⁺ ions. This enhances ⁵D₀ level emission via charge transfer. The radiative and experimental lifetimes of the ⁵D₀ level increase linearly with B₂O₃ content. This results in high quantum efficiency (η) ranging from 74 to nearly 84%. Tunable chromaticity, as defined by the CIE 1931 standard, was achieved, resulting in a warm orange-red color with high brightness. These new glasses have a variety of potential laser-related applications. Full article

Glass-insulated terminals (GITs) are widely used in high-reliability microelectronic systems, where glass fall-offs in the sealing region may seriously degrade the reliability of the microelectronic component and further degrade the device reliability. Automatic inspection of such defects is challenging due to strong light reflection, irregular defect appearances, and limited defective samples. To address these issues, a coarse-to-fine machine-learning framework is proposed for glass fall-off detection in GIT images. By exploiting the circular-ring geometric prior of GITs, an adaptive sector partition scheme is introduced to divide the region of interest into sectors. Four categories of sector features, including color statistics, gray-level variations, reflective properties, and gradient distributions, are designed for coarse classification using a gradient boosting decision tree (GBDT). Furthermore, a sector neighbor (SN) feature vector is constructed from adjacent sectors to enhance fine classification. Experiments on real industrial GIT images show that the proposed method outperforms several representative inspection approaches, achieving an average IoU of 96.85%, an F1-score of 0.984, a pixel-level false alarm rate of 0.55%, and a pixel-level missed alarm rate of 35.62% at a practical inspection speed of 32.18 s per image. Full article

Using multifunctional dual-cure smart bioactive resin luting agents (DRLs) offers benefits in adhesive dentistry, but their optical stability remains a concern. Their pre-cured form is a shear-thinning structure with thixotropic gel-like behavior. The effect of their hydrophilicity and different thicknesses of nanoceramic hybrid on the final shade of milled esthetic restorations needs further investigation. This study examined how the optical function deterioration of dual-cure smart bioactive resin luting agents used to bond a CAD/CAM nano-ceramic hybrid composite would influence the restoration’s final shade at three different thicknesses. A nanoceramic hybrid composite (GD) was cut into blocks and grouped by thickness (0.8, 1.0, 1.5 mm). Ten blocks from each group were assigned to subgroups based on the DRL type: Panavia SA Universal (PN), Predicta Bioactive (PR), and ACTIVA BioACTIVE (AC). Color and whiteness changes after a 24 h/day (24 days) coffee immersion were analyzed using statistical methods (ANOVA and Tukey’s HSD for ΔE₀₀; Welch’s ANOVA and Games-Howell for ΔWI_D and ΔL*). DRL type significantly affected ΔE₀₀, ΔWI_D, and ΔL* (p < 0.001). All materials showed the least color change and optical function deterioration at a restoration thickness of 1.5 mm, which was below the acceptability threshold (AT). Despite PR’s bioactive functionality, it maintained its primary optical function with the least color change at GD thicknesses of 1.0 and 1.5 mm (p < 0.001). AC exhibited the greatest ΔE₀₀ above AT, especially at a thickness of 0.8 mm (p < 0.001). ΔL*, ΔE₀₀, and ΔWI_D varied significantly based on DRL type, GD thickness, and the interaction between DRL and thickness (p < 0.05). This suggests that although dual-cure smart DRLs containing bioactive glasses are advantageous, their optical function shifts may become more noticeable in thin, translucent restorations. Increasing the restoration thickness can help mitigate this by altering the optical pathway. Full article

Background: Bioactive composite resins combine the esthetic and mechanical properties of resin composites with therapeutic functions such as ion release, remineralization, and caries inhibition. While in vitro studies suggest promising bioactivity, their clinical performance in permanent teeth remains uncertain. Objective: This systematic review and meta-analysis critically appraised randomized controlled trials and prospective clinical studies to determine whether bioactive composites offer superior clinical performance compared to conventional resin composites and glass ionomer-based materials. Methods: Electronic databases (PubMed/MEDLINE, Scopus, Web of Science, Google Scholar) were searched for eligible studies (2018–2025). Clinical outcomes assessed restoration survival, marginal integrity, secondary caries, postoperative sensitivity, and esthetic outcomes (color match). Data were pooled using a random-effects model, and risk of bias was assessed with Cochrane criteria. Results: Twenty-two trials met the inclusion criteria. No significant differences were found between bioactive and control restorations for survival/retention (RD = 0.01; 95% CI, –0.01 to 0.03), marginal adaptation (RD = 0.02; 95% CI, –0.02 to 0.06), secondary caries (RD = 0.01; 95% CI, –0.01 to 0.03), or postoperative sensitivity (RD = 0.01; 95% CI, –0.02 to 0.04), with negligible heterogeneity (I² = 0–4%). For color match, glass ionomer restorations showed significantly poorer outcomes (RD = –0.23; 95% CI, –0.31 to –0.14; p < 0.00001; I² = 98%), while conventional resin composites had a slight but significant advantage over bioactive composites (RD = 0.07; 95% CI, 0.02 to 0.12; p = 0.003; I² = 76%). Most studies presented moderate risk of bias and short-term follow-up (<36 months). Conclusions: Current evidence indicates that bioactive composites perform comparably, but not superior, to conventional restoratives in permanent teeth. The discrepancy between laboratory bioactivity and clinical effectiveness highlights the need for long-term, well-designed clinical trials with standardized outcome reporting. Full article

Background/Objectives: This systematic review and meta-analysis aimed to evaluate the clinical performance and survival of bulk-fill resin composite restorations in posterior primary teeth, compared with conventional resin composites and glass ionomer cements (GICs). Methods: The protocol was registered in PROSPERO (CRD42024539097) and conducted according to PRISMA guidelines. Electronic searches were performed in PubMed, Embase, Web of Science, Scopus, and Cochrane databases up to December 2025. Randomized clinical trials (RCTs) evaluating bulk-fill resin composite restorations in primary molars were included. Restoration survival was considered the primary clinical endpoint. Secondary outcomes included marginal integrity, marginal discoloration, color match, postoperative sensitivity, secondary caries, retention, and anatomical form, assessed using USPHS or FDI criteria. Meta-analyses were performed for color match, marginal discoloration, and marginal integrity using a random-effects model. Comparisons involving GICs were synthesized descriptively. Risk of bias was assessed using the RoB 2 tool, and certainty of evidence was evaluated using GRADE. Results: Six RCTs involving 1220 restorations in children aged 3 to 10 years were included, with follow-up periods ranging from 6 to 24 months. Survival rates were high across all materials. Meta-analyses up to 12 months showed no significant differences between bulk-fill and conventional resin composites for color match, marginal discoloration, or marginal integrity. Most RCTs were judged as having low risk of bias, with one study presenting some concerns. The certainty of evidence was rated as moderate, mainly due to imprecision related to sample size and limited reporting of confidence intervals. Conclusions: Bulk-fill resin composites demonstrate clinical performance and survival comparable to conventional resin composites in posterior restorations of primary teeth over follow-ups of up to 12 months. Based on RCTs with predominantly low risk of bias and moderate certainty of evidence, bulk-fill composites represent a reliable and efficient restorative option in pediatric dentistry. Full article

Two amide-preformed aromatic diamine monomers, N,N-bis(4-(3-aminobenzamido)phenyl)-N’,N’-bis(4-methoxyphenyl)-1,4-phenylenediamine (m-6) and N,N-bis(4-(4-aminobenzamido)phenyl)-N’,N’-bis(4-methoxyphenyl)-1,4-phenylenediamine (p-6), were synthesized and utilized to prepare two series of electroactive poly(amide-imide)s (PAIs) through a two-step polycondensation reaction with commercially available aromatic tetracarboxylic dianhydrides. The obtained polymers exhibited solubility in various polar organic solvents, and most of them could form transparent, flexible films via solution casting. Thermal analysis indicated glass transition temperatures (T_g) ranging from 250 °C to 277 °C, as measured by DSC, with no significant weight loss observed before 400 °C in TGA tests. Cyclic voltammograms (CV) of the polymer films on ITO-coated glass substrates revealed two reversible oxidation redox pairs between 0.67 and 1.04 V vs. Ag/AgCl in an electrolyte-containing acetonitrile solution. The PAI films showed stable redox activity with high optical contrast both in the visible and near-infrared regions, transitioning from colorless in the neutral state to green and blue in the oxidized states. Furthermore, the polymer films retained good electrochemical and electrochromic stability even after more than 100 cyclic switching operations. The PAIs displayed outstanding electrochromic performance, including high optical contrast (up to 95%), rapid response times (below 4.6 s for coloring and 5.7 s for bleaching), high coloration efficiency (up to 240 cm²/C), and low decay in optical contrast (less than 5% after 100 switching cycles for most PAIs). Full article

Organic light-emitting diodes (OLEDs) have emerged as a leading high-resolution display and lighting technology, as well as for photo-therapeutic applications, due to their light weight, flexibility, and excellent color rendering. However, achieving long-term thermal stability and high energy efficiency remains a principal issue for their widespread adoption. Strong thermal robustness in OLED emitter materials is a critical parameter for achieving long device lifetimes, stable film morphology, reliable high-temperature processing, and sustained interface integrity in high-performance hosts. Bipolar emitters RB14 (N-(9-ethylcarbazole-3-yl)-4-(diphenylamino)phenyl-9H-carbazole-9-yl-1,8-naphthalimide), RB18 (N-phenyl-4-(diphenylamino)phenyl-9H-carbazole-9-yl-1,8-naphthalimide), and RB22 (N-phenyl-3-(2-methoxypyridin-3-yl)-9H-carbazole-9-yl-1,8-naphthalimide) were newly synthesized. RB18 is a yellow bipolar OLED emitter that has a glass transition temperature (T_g) of 162 °C and thermal durability (T_d) of 431 °C, which is the highest reported value for naphthalimide-based bipolar emitter derivatives for yellow OLEDs. Meanwhile, RB14 and RB22 are green OLED emitters that have glass transition temperatures (T_g) of 133 °C and 167 °C, and thermal durabilities (T_d) of 336 °C and 400 °C, respectively. We have fabricated OLED devices using these bipolar emitters dispersed in CBP host matrix, and we have found that the maximum EQEs (%) for RB14, RB18, and RB22 emitter-based devices are 7.93%, 3.40%, and 4.02%, respectively. For confirmation of thermal stability, we also used UV-visible spectroscopy measurements at variable temperatures on annealed spin-coated glass films of these emitter materials and found that RB22 is the most thermally stable emitter among these materials. Full article

Outdoor glass is subject to degradation due to environmental factors, which alter its physical and chemical properties depending on the exposure conditions. Studying glass weathering and the effectiveness and durability of conservation treatments is necessary for developing optimal conservation strategies for glass heritage objects. Here, an accelerated aging protocol based on actual environmental data is successfully employed to replicate weathering caused by rain runoff, temperature, humidity and UVA radiation in unsheltered conditions. Two types of silicate glass with traditional compositions were artificially aged to investigate the corrosion processes and produce representative weathered substrates for applying and aging protective treatments. The performance of two recently marketed Siox-5 sol–gel systems was compared with that of Paraloid B72. Glass specimens, as well as leaching rain solutions, were analyzed with different techniques, including SEM/EDS, FTIR-ATR, color measurements and MP-AES. The composition of the glass influences weathering patterns, which in turn affect coating adhesion and overall performance. Sol–gel coatings demonstrate good chemical stability and tend to adhere more effectively to degraded surfaces than to well-preserved ones. The coatings exhibit varying degrees of sensitivity to environmental factors, with one of the sol–gel systems generally performing better than the others under the considered exposure conditions. Full article

Augmented reality (AR) near-eye displays (NEDs) couple microdisplay image light to the human eye via integrated optical modules, enabling seamless virtual–real fusion. As core components that synergistically transmit and diffract light, diffractive waveguides are promising for next-generation AR NEDs but face two bottlenecks: compromised full-color performance in single-layer structures caused by grating dispersion and lack of scalable fabrication technologies. To address these, we first propose a mass-production-compatible workflow based on deep ultraviolet (DUV) lithography for large-area nanostructured optics. This workflow enables high-precision wafer-level production with 200 mm wafers and nine dies per wafer, overcomes scalability issues, and is fully compatible with straight-configuration nanostructures to ensure manufacturing feasibility. Leveraging this workflow, we develop a single-layer diffractive waveguide system for AR NEDs, which comprises a thin glass substrate, a broadband high-efficiency multi-layer dielectric in-coupler, and a 2D out-coupler that concurrently expands and out-couples light. Rigorous coupled wave analysis (RCWA) optimized coupler diffraction, while ray tracing refined guided light intensity and significantly improved exit pupil uniformity. This work establishes a foundation for full-color, high-efficiency AR waveguides and provides a scalable paradigm for large-area nanostructured optical systems such as telescopes and lithography equipment. Full article

Unused glass waste represents a potentially valuable secondary raw material for the production of construction materials. This study aimed to investigate the chemical and structural transformations occurring in soda-lime container glasses of different chemical compositions when exposed to alkaline environments. Such alkaline conditions are characteristic of processes involved in the production of lime–sand materials or Portland cement-based composites, where they are essential for the occurrence of pozzolanic reactions. The investigation was conducted on powders derived from three types of container glass differing in color, which were stored in Ca(OH)₂ and NaOH solutions. The samples were analysed using X-ray diffraction (XRD), differential thermal and thermogravimetric analysis (DTA–TG), and scanning electron microscopy (SEM). The results confirmed that all tested glasses exhibited pozzolanic reactivity, although differences were observed in the composition of the reaction products and the kinetics of the transformation processes. A deeper understanding of these differences may contribute to more effective utilization of waste glass as a raw material in the manufacturing of construction materials. Full article

Second-grade watermelons are a lycopene-rich by-product currently discarded despite their potential for valorization. This study aimed to develop a consumer-accepted alcoholic liqueur by alcoholic maceration of watermelon pulp, optimizing the formulation for lycopene retention, antioxidant activity, and sensory quality. Three pulp ratios (15, 20, and 25% v/v) were macerated in 39% v/v cane alcohol for 5 days at 20 °C. The 20% pulp formulation (T2) achieved the best balance of lycopene (8.6 mg L⁻¹), DPPH antioxidant activity (580 µmol TE L⁻¹), redness (CIE a* = 14.1), and overall acceptability (7.6/9). Under nitrogen-flushed amber glass, T2 retained ≥82% lycopene and ≤10% antioxidant loss after 90 days at 20 °C, following first-order degradation kinetics (Ea = 43 kJ mol⁻¹). A minimum shelf-life of three months is projected under these experimental conditions. Life-cycle screening indicates 0.84 kg CO₂-eq L⁻¹, with a 1.9-year payback and 1.7 t CO₂-eq savings per ton of rescued fruit compared to landfill. These findings demonstrate the feasibility of producing a shelf-stable, naturally colored craft spirit with watermelon flavor, aligning with consumer preferences and circular economy principles in the alcoholic beverage sector. Full article