Texture of cooked germinated brown rice subjected to freeze-thaw treatment and its improvement by magnetic field treatment.

This study aimed to investigate the textural changes of cooked germinated brown rice (GBR) during freeze-thaw treatment and propose a strategy for enhancing its texture using magnetic field (MF). Seven freeze-thaw cycles exhibited more pronounced effects compared to 7 days of freezing, resulting in increases in GBR hardness by 85.59 %-164.36 % and decreases in stickiness by 10.34 %-43.55 %. Water loss, structural damage of GBR flour, and starch retrogradation contributed to the deterioration of texture. MF mitigated these effects by inhibiting the transformation of bound water into free water, reducing water loss by 0.39 %-0.57 %, and shortening the phase transition period by 2.0-21.5 min, thereby diminishing structural damage to GBR flour and hindering starch retrogradation. Following MF treatment (5 mT), GBR hardness decreased by 21.00 %, while stickiness increased by 45.71 %. This study elucidates the mechanisms through which MF enhances the texture, offering theoretical insights for the industrial production of high-quality frozen rice products.

Influence of light-polymerizing units and zirconia on the physical, chemical and biological properties of self-adhesive resin cements.

BACKGROUND: Self-adhesive resin cements (SARCs) are widely used for fixed prostheses, but incomplete cleaning near the gingival margin can cause inflammation. However, the factors influencing cement properties and the biological response of gingival fibroblasts to cement eluates are not well understood. This study examines the impact of two light-polymerizing units (LPUs) on the physical and chemical properties of two SARCs under simulated clinical conditions, as well as the subsequent response of human gingival fibroblasts (hGFs) to these eluates. METHODS: Dental cement discs of SARCs were polymerized using Kerr DemiPlus and 3 M Elipar DeepCure-S LED LPUs with or without a 2-mm thick zirconia screen. Physical properties (microhardness, surface roughness, residual monomers) were evaluated. hGFs' cell viability, wound healing potency, and gene expression were assessed. RESULTS: Both Maxcem and RelyX exhibited reduced microhardness and increased surface roughness when polymerized through zirconia or with DemiPlus LPU. Higher residual monomers (HEMA and GDMA in Maxcem; TEGDMA in RelyX) concentration was observed with DemiPlus and zirconia polymerization. Maxcem polymerized with DemiPlus exhibited lower cell viability, impaired healing, and altered gene expression in hGFs compared to those polymerized with Elipar LPU. Gene expression changes included downregulated NRF2 and HO-1 and upregulated CCR-3. CONCLUSIONS: Light-polymerizing Maxcem through zirconia with DemiPlus LPU compromised SARCs' properties, leading to higher residual monomers and negatively impacting hGFs' viability, healing, and gene expression. Careful material selection and polymerization techniques are crucial to minimize adverse effects on surrounding tissues. CLINICAL SIGNIFICANCE: Clinicians should exercise caution when using LPUs and SARCs, especially when polymerizing through zirconia. This will help optimize the physical and chemical properties of SARCs and minimize potential adverse effects on the surrounding gingival soft tissues.

Effect of Adding Different Concentrations of Silver Nanoparticles on Flexural Strength and Microhardness of Different Denture Base Materials.

AIM: This study aimed to evaluate the effect of adding different concentrations of silver nanoparticles (AgNPs) on the flexural strength and microhardness of various denture base materials. MATERIALS AND METHODS: For this study, a total of 60 specimens were used and divided into equal groups. The first group consisted of heat-cured acrylic resin (Vertex-Germany), while the second group consisted of thermoplastic resin (Breflex 2nd edition, Germany). The samples were created using a split brass mold with dimensions of 65 × 10 × 2.5 mm, in accordance with the specifications of the American Dental Association (specifically No. 12 for flexural and microhardness). Following this, the samples were divided into three groups (A, B, and C) based on different concentrations of AgNPs (0, 2, and 5%). The flexural and microhardness of the samples were assessed using a universal testing machine and the Vickers hardness test, respectively. The data were gathered, organized, and analyzed using statistical methods. RESULTS: The flexural strength findings showed a significant difference between the two groups. Also, there was a considerable decrease in the average value of the acrylic group as the concentrations of AgNPs rose, while the flexural strength of the thermoplastic group notably improved. Regarding microhardness, the results showed a significant difference between the two groups. It showed that the mean value of both groups increased with increasing concentrations of AgNPs. CONCLUSION: Within the limitations of laboratory testing conditions of this study, it was discovered that AgNPs negatively impact the flexural strength of acrylic resins. Furthermore, an increase in the concentration of AgNPs was found to be directly related to the flexural strength of thermoplastic resin and the microhardness of both groups. CLINICAL SIGNIFICANCE: The concentration of AgNPs has a significant impact on certain mechanical properties of denture base materials, but it is important to consider their potential toxicity. How to cite this article: El-Hussein IG. Effect of Adding Different Concentrations of Silver Nanoparticles on Flexural Strength and Microhardness of Different Denture Base Materials. J Contemp Dent Pract 2024;25(5):417-423.

Physical and mechanical properties of hard seed coat on the example of Gleditsia triacanthos L.

The microhardness of individual morphological structures of the hard coat of the seed of Gleditsia triacanthos L. was measured. Measurements were made on the transverse and frontal planes. Based on the differences in the hardness of the two planes, the anisotropy of the seed coat was revealed. The entire seed coat has a special hardness which can be compared with the hardness of hardwood like oat wood. An interesting feature was the hardness of the endosperm, comparable to the hardness of the epidermis. Further study of the processes that occur in seeds during imbibition is based on the obtained data. Mathematical modeling methods are the most promising for these tasks; they will help to identify the points of fragility and the points of the greatest tension in the seed coat. These results will allow us to find the best ways to destroy the seed coat and to accelerate the germination. Research of physical properties of the seed coat is of practical importance in the fact that in the future it will allow reducing of the hard-seeding and increasing the germination of seeds. The obtained data allows us to represent the initial hardness of the seed coat.

Role of the novel aloe vera-based titanium dioxide bleaching gel on the strength and mineral content of the human tooth enamel with respect to age.

There has been an increased demand for dental bleaching globally irrespective of age and gender. Main drawbacks associated with conventional tooth bleaching agents have been compromised strength and mineral-content of tooth enamel which results in sensitivity, discomfort, roughness, and structure loss of human teeth. Currently, nanoparticles synthesized by green synthesis have gained popularity especially in medical and dental applications because of their versatile and beneficial nano-scaled features. Titanium dioxide nanoparticles (TiO2Nps) in this study were prepared from green ecofriendly source using the aloe vera plant extract and were then characterized via dynamic light scattering (DLS), scanning electron microscope (SEM), X-ray diffraction spectroscopy (XRD), and energy dispersive X-ray (EDX), for size, shape, composition and true-phase. These TiO2 Nps were incorporated in commercial bleaching gel containing hydrogen peroxide to form a novel TiO2-bleaching gel which was used to bleach extracted anterior teeth belonging to four different age groups: 20-29 years, 30-39 years, 40-49 years and ≥50 years. These teeth were investigated for micro-hardness (Vickers microhardness tester) and mineral-content (EDX spectroscopy) including sodium, magnesium, phosphorus, calcium in an in-vitro environment both before and after bleaching. Results revealed that TiO2 Nps prepared by aloe vera plant were nanos-sized of about 37.91-49 nm, spherical shape, true anatase phase with pure titanium and oxygen in their composition. The values of Vickers micro-hardness and mineral-content (Na, Mg, P, Ca) of enamel specimens belonging to different age groups enhanced in a linear pattern before bleaching with the increase in age (p value < 0.05). There was negligible reduction observed in Vickers micro-hardness and mineral-content elements (Na, Mg, P, Ca) of all enamel specimens belonging to different ages after the bleaching (p value > 0.05). The novel TiO2-bleaching gel prepared was effective enough in preventing the declination in Vickers micro-hardness strength and mineral-content of all the enamel specimens belonging to different age groups even after the bleaching procedure which makes it a promising biomaterial.

Effect of peroxide-free and peroxide-based in-office bleaching on the surface and mechanical properties of CAD/CAM esthetic restorative materials.

The study aimed to investigate the influence of H2O2-based and H2O2-free in-office bleaching on the surface and mechanical attributes of CAD/CAM composite blocks. CAD/CAM composite blocks from five different composite materials (CC1, CC2, CC3, CC4, and CC5) were randomly divided into two groups according to bleaching application (H2O2-based and H2O2-free). The surface topography, morphology, nanohardness, elastic modulus, flexural strength, and fracture toughness were measured. A paired and unpaired sample t-tests gauged the effect of pre- and post-bleaching on the substrates. The estimated mean differences (before-after bleaching) suggested an increase in surface roughness for two materials CC2 and CC4, and a significant decrease in nanohardness for material CC4 and in elastic modulus for materials CC2 and CC4 with H2O2-based bleaching, whereas H2O2-free bleaching resulted in changes compatible with no change in these properties. Flexural strength and fracture toughness showed no evidence of changes, irrespective of the bleaching gel used. Scanning electron microscopic analysis revealed erosive effects and micropore formation due to H2O2-based bleaching. H2O2-based bleaching deteriorates the surface of CAD/CAM composite materials while H2O2-free bleaching gel had an insignificant effect on both surface and bulk properties. The clinician should carefully evaluate the potential effects of H2O2-based bleaching on the surface properties of CAD/CAM composites.

In-vitro and in-vivo comparative studies of treatment effects on enamel demineralization during orthodontic therapy: implications for clinical early-intervention strategy.

OBJECTIVES: This study aimed to investigate if CPP-ACP / infiltrating resin was superior in treating enamel demineralization during orthodontic therapy compared with fluoride varnish, in order to provide early-intervention implications for dental professionals. MATERIALS AND METHODS: In the in-vitro study, premolars were grouped into four: remineralization with fluoride varnish / CPP-ACP, sealing with infiltrating resin, and negative control. Experimental demineralization of enamel surfaces was analyzed using techniques of QLF, SEM, EDS and micro-hardness testing. An in-vivo intervention study was conducted on patients randomly assigned into three groups. At the baseline and every-3-month follow-up, QLF parameters were compared temporally and parallelly to yield potential implications for promotion in clinical practice. RESULTS: The in-vitro study performed on 48 experimental tooth surfaces demonstrated that sealing with infiltrating resin reduced enamel surface porosity and increased surface micro-hardness significantly. In the in-vivo intervention study on 163 tooth surfaces, it was suggested that for those who meet the criteria of -10 < ΔF < -6 and - 1000 < ΔQ < -20 at the baseline, all these treatment methods could achieve acceptable outcomes; with the rising of absolute values of ΔF and ΔQ, sealing with infiltrating resin showed more evident advantages. CONCLUSION: For enamel demineralization during orthodontic therapy, all the treatment methods involved in this study showed acceptable effectiveness but had respective characteristics in treatment effects. QLF parameters could be used as indicators for clinical early-intervention strategy with regards to this clinical issue. CLINICAL RELEVANCE: With QLF parameters, clinical early-intervention strategy for enamel demineralization during orthodontic therapy could be optimized.

On the suitability of photocuring-assisted DIW for manufacturing complex prosthesis from commercial dental composites.

A 3-D printing method to produce dental prostheses of complex shapes from a commercial, photocurable resin-ceramic slurry is developed and optimized. The microstructure, mechanical properties and wear behavior of the resulting material are evaluated and compared with a conventional/control sample and other ceramic-polymer dental composites. Commercial resin-ceramic dental slurries can be successfully extruded and appropriately photocured in a low cost 3-D printing system to produce cost-efficient complex dental parts that could be used in indirect restorations. The printing process does not appreciably introduce defects in the material and the 3-D printed composites exhibit mechanical properties (hardness, elastic modulus) and wear resistance comparable to the control material and analogous, conventional dental composites. The main wear mechanisms under sliding contact against a hard antagonist are plastic deformation at the asperity level and ceramic particle pull-out due to filler/matrix interfacial weakness.

Multiparametric Cranberry (Vaccinium macrocarpon Ait.) Fruit Textural Trait Development for Harvest and Postharvest Evaluation in Representative Cultivars.

Fruit texture is a priority trait that guarantees the long-term economic sustainability of the cranberry industry through value-added products such as sweetened dried cranberries (SDCs). To develop a standard methodology to measure texture, we conducted a comparative analysis of 22 textural traits using five different methods under both harvest and postharvest conditions in 10 representative cranberry cultivars. A set of textural traits from the 10%-strain compression and puncture methods were identified that differentiate between cultivars primarily based on hardness/stiffness and elasticity properties. The complementary use of both methodologies allowed for a detailed evaluation by capturing the effect of key texture-determining factors such as structure, flesh, and skin. Furthermore, the high effectiveness of this approach in different conditions and its ability to capture high phenotypic variation in cultivars highlights its great potential for applicability in various areas of the value chain and research. Therefore, this study provides an informed reference for unifying future efforts to enhance cranberry fruit texture and quality.

Comparing the remineralization potential of undemineralized dentin powder versus chicken eggshell powder on artificially induced initial enamel carious lesions: an in-vitro investigation.

BACKGROUND: White spot lesions are a widespread undesirable effect, especially prevalent during fixed orthodontic treatments. The study compared the in vitro enamel remineralization potential of undemineralized dentin matrix (UDD) versus chicken eggshell powder (CESP) for artificially induced enamel lesions. METHODS: 100 caries-free and sound maxillary premolars were randomly divided into four groups each contain 25 teeth: Group I (Baseline): No treatment was done to the enamel surface. Group II (Negative control ): The enamel surface of the teeth underwent demineralization using demineralizing solution to create artificial carious lesions then kept in artificial saliva. Group III (CESP treated): After demineralizing the tooth surface, the teeth have been suspended in the CESP remineralizing solution. Group IV (UDD treated): After enamel demineralization, the teeth were suspended in UDD remineralizing solution. The remineralization potential was assessed by Vickers microhardness testing, scanning electron microscopic examination (SEM), and energy dispersive X-ray (EDX). RESULTS: The current study demonstrated an increase in the mean microhardness of CESP and UDD-treated groups; however, It was nearer to the baseline level in the UDD group. SEM imaging revealed greater enamel remineralization in the UDD group compared to the remaining groups. The UDD group disclosed complete coverage for the prismatic enamel compared to the CESP group, which revealed a partially remineralized enamel surface. Interestingly, the Ca/P ratio increased significantly in the CESP group compared to the negative control group. In contrast, a higher significant increase in the mean Ca/P ratios was recorded in the UDD group compared to the test groups. CONCLUSION: biomimetic UDD and CESP powder should be utilized to treat enamel early carious lesions. However, UDD demonstrated the most significant remineralization potential.

Evaluation of nanohardness, elastic modulus, and surface roughness of fluoride-releasing tooth colored restorative materials.

Recently, interest in tooth-colored fluoride-releasing dental materials has increased. Although physical and mechanical properties such as surface hardness, elastic modulus and surface roughness of the restorative materials have been investigated, the effect of different immersion media on these properties is still controversial. The aim of this study was to evaluate the nanohardness, elastic modulus and surface roughness of the fluoride release of tooth-colored restorative materials after immersion in acidic beverages. Prepared samples of three restorative materials (a highly viscous glass ionomer (EQUIA Forte; GC, Tokyo, Japan), a compomer (Dyract XP; Dentsply, Weybridge, UK), and a bioactive restorative material (Activa BioACTIVE; Pulpdent, MA, USA)) were randomly divided and immersed in distilled water, a cola and an orange juice for one week. The HYSITRON T1 950 TriboIndenter device (Hysitron, USA) with the Berkovich diamond indenter tip was used for all measurements. The nanohardness and elastic modulus of the samples were measured by applying a force of 6000 µN to five different points on the sample surface. Surface roughness measurements were evaluated on random samples by scanning five random 40 × 40 µm areas. The properties were measured at the initial and one week after immersion. The values of nanohardness, elastic modulus and surface roughness were tested for significant differences using a two-way analysis of variance (ANOVA) with repeated measures (p < 0.05). Tukey's honest significant difference (HSD) test was used for multiple comparisons. AB (Activa BioACTIVE) had the highest initial mean values for nanohardness. After post-immersion, the highest mean value for elastic modulus was the initial AB value. The lowest mean value for roughness of 100.36 nm was obtained for the initial DX (Dyract XP) measurement. Acidic beverages had a negative effect on the nanohardness, elastic modulus and surface roughness of the restorative materials.

A portable lateral flow distance-based paper sensor for drinking water hardness test.

Hardness is one of the basic parameters of water, and a high-level hardness of drinking water may be harmful to human health. Thus, it is very important to monitor drinking water hardness. In this work, a portable lateral flow distance-based paper sensor for the semi-quantitative detection of drinking water hardness is demonstrated. In the presence of Ca2+/Mg2+, the hydrogel can be formed via the chelation between sodium alginate and Ca2+/Mg2+, inducing a phase separation process. The viscosity change of the sodium alginate solution is directly related to the Ca2+/Mg2+ concentration and can be determined by the water lateral flow distance on test strips. The sensor successfully realizes the quantification of Ca2+ and Mg2+ in the range of 0-10 mmol L-1 and 4-20 mmol L-1, respectively. The recoveries are found varied from 95% to 108.9%. The water hardness is acceptable for drinking if the Cr values lies in the range of 0.259 to 0.419, and it is high with the Cr value above 0.595. Remarkably, the performance of the sensor is comparable with the commercial kit for real water samples, which avoids the subjective judgment. Overall, this method provides a portable approach for semi-quantitative detection of drinking water hardness with the merits of convenience and low cost, which shows great potential for the potential application.

Sprouted wheat wholemeal as a techno-functional ingredient in hard pretzels.

There has been a growing interest in incorporating sprouted wheat wholemeal (SWW) into whole grain baking, driven by its heightened nutritional content and improved nutrient bioavailability. This study aimed to assess how substituting soft wheat flour (SWF) with various levels of wheat wholemeal (unsprouted and sprouted) impacts the quality and sensory characteristics of hard pretzel sticks, which are globally enjoyed as popular snacks. The dough samples containing wholemeal did not demonstrate the same extensibility as the SWF dough sample. Additionally, substituting SWF with wholemeal increased the resistance to extension. Analysis of the Raman spectra of SWF and two other selected dough samples containing 75 % unsprouted wheat wholemeal (UWW) or SWW indicated α-helix as the dominant protein secondary structure. As the ratio of wholemeal to SWF increased in both unsprouted and sprouted wheat pretzel samples, protein and fiber content increased and starch content decreased, resulting in a decreased peak viscosity in an RVA (Rapid Visco Analyzer) test. The findings also showed no significant difference in hardness between the SWF pretzel sample and all other samples (p > 0.05), except when SWF was replaced with the highest level (75 %) of SWW, resulting in a significantly softer texture. Color analysis revealed that the introduction of wholemeal led to a decrease in the L* value, indicating a darker surface appearance in the samples, likely due to the presence of bran. Finally, sensory evaluation determined that replacing SWF with 25 % SWW resulted in the creation of a sample most similar to SWF in terms of sensory attributes. This research paves the way for future studies and advancements in the formulation and analysis of pretzel dough, creating opportunities to improve both the quality of the product and consumer satisfaction.

Antimicrobial hard denture reliners using quaternary ammonium methacryloxy silicate (K18 QAMS) and K18-functionalized filler.

OBJECTIVE: To determine the effects of adding a quaternary ammonium methacryloxy silicate (K18) and K18-functionalized filler (K18-Filler) on the material and antimicrobial properties of a hard denture reline material. MATERIALS AND METHODS: 30% K18 in methyl methacrylate (K18-MMA; 0-20 wt% of reliner) and K18-Filler (0-30 wt% of reliner) were incorporated into KoolinerTM hard denture reliner. KoolinerTM served as the control. The cure (Shore A hardness), hydrophilicity (contact angles), mechanical (3-point bend test), water sorption, and antimicrobial properties against Streptococcus mutans, S. sanguinis, and Candida albicans were determined. RESULTS: Most K18 groups cured well and had comparable Shore A hardness values (range ~52 to 70 DHN) to that of controls (67.2 ± 1.8 DHN; Bonferroni corrected p > 0.0003). Even the softest group had hardness values within the range of commercial products. Half of the K18 groups had comparable contact angles to that of controls (range ~75° to 80° vs 83.41° ± 2.66°; Bonferroni corrected p > 0.0003), and most were within the range of commercial liners. K18-MMA and K18-Filler increased modulus but decreased ultimate transverse strength (UTS). All experimental groups had comparable or higher moduli than controls (range ~966 to 2069 MPa vs 1340 ± 119 MPa; Bonferroni corrected p < 0.0003), but only half of the experimental groups had comparable UTS to that of controls (range ~41 to 49 MPa vs 55.8 ± 1.5 MPa; Bonferroni corrected p > 0.0003). The 15% and 20% K18-MMA with 30% K18-Filler groups had significant antimicrobial activity against all three microbes (p < 0.05). However, the 15% and 20% K18-MMA with 30% K18-Filler groups had significantly higher water sorption at early time points (p < 0.05). After 8 weeks, they were comparable to each other (p > 0.05). CONCLUSIONS: K18-MMA and K18-Filler are promising antimicrobial additives that produce hard denture liners with material properties within the range of commercial products and significant antimicrobial properties against S. mutans, S. sanguinis, and C. albicans. Further development is needed to reduce water sorption.

Implications of Histological and Ultrastructural Characteristics on the Chemical and Mechanical Properties of Hypomineralised Enamel and Clinical Consequences.

Molar incisor hypomineralisation (MIH) is a qualitative type of enamel defect, which occurs due to a failure in the biomineralisation process of the enamel organic matrix during amelogenesis. The tooth enamel affected by MIH shows changes in its chemical, structural, and mechanical properties, leading to different clinical repercussions. The color of MIH opacities varies from opaque white to yellow/brown, and elemental analyses of these lesions show a lower calcium and phosphate content, minerals that are more abundant in sound enamel. Furthermore, the incorporation of other molecules occurs, such as carbonate, a component that provides a greater degree of solubility, thus making hypomineralised enamel more susceptible to posteruptive fractures. At a structural level, the layer of hydroxyapatite crystals appears to be disorganized, with morphological changes, implying a greater degree of porosity in the structure. The increase in porosity of the structure may be associated with dental hypersensitivity, a common clinical repercussion among patients with MIH. Among the mechanical properties, a decrease in hardness and modulus of elasticity occurs, and this also makes the enamel more fragile. Deficiency in biomineralisation can be caused by changes in the function of ameloblasts or by failures at the intercellular junction that result in lower activity of proteases such as MMP-20 and KLK4. The increase in proteins in the organic matrix of enamel impairs the growth and incorporation of minerals into the hydroxyapatite crystals, so that the enamel becomes hypomineralised and has larger organic content, thus having an impact on its properties. These changes present in the enamel with MIH help to explain the clinical repercussions caused by this condition.

Effect of duration and infection control barriers of light curing unit on hardness of Bulk Fill composite resin.

Background: This study aimed to investigate the impact of the duration of light curing unit (LCU) usage and the use of infection control barriers on the hardness of Bulk Fill composite resin after curing. The hypotheses were that extended usage of the LCU would not reduces its output power and resin hardness, and that the presence of polyethylene film barriers exacerbates the reduction in resin hardness. Methods: Based on the absence or presence of polyethylene film (PE) and the number of layers used, a 3M LED curing light (EliparTM DeepCure-S; 3M ESPE, St Paul, MN, USA) was divided into three groups: PE0, PE1, and PE3. The curing light was used 30 times daily for 20 s per exposure, at frequencies of 0, 6, and 12 months. Maximum output power tests were conducted for each group of curing lights. Custom-made plastic modules were used to stack Bulk Fill composite resin (Filtek Bulk Fill Posterior Restorative; 3M ESPE) to a thickness of 4 mm. Each group of curing lights was used to cure the modules in a direct contact manner for 20 s. Vickers hardness measurements were taken at the top and bottom surfaces of the resin specimens using a digital microhardness tester. A one-way or two-way ANOVA analyzed the power of LCUs, Vickers hardness of Bulk Fill composite resin, and hardness decrease percentage across groups. Pairwise comparisons used the Tukey test (α = 0.05). Results: As the duration of usage increased, both the power of the curing light and the hardness of the resin significantly decreased. Significant differences were observed in power and resin hardness among the PE0, PE1, and PE3 groups. When the duration of usage was 6 months or less, only multi-layered PE films led to a significant increase in the percentage decrease of hardness of cured resin from top to bottom. However, at 12 months, both single-layer and multi-layered PE films resulted in a significant increase in the percentage decrease of hardness of cured resin from top to bottom. Conclusion: The output power of the light curing unit decreases with prolonged usage, thereby failing to meet the curing requirements of Bulk Fill composite resin. The use of single-layer PE as an infection control barrier is recommended.

The effect of thermal aging on microhardness and SEM/EDS for characterisation bioactive filling materials.

BACKGROUND: The aim of this study is to evaluate the surface microhardness, surface chemical composition of bioactive restorative materials pre- and post- thermal aging. METHOD: A total of 200 disc-shaped samples were prepared by using the materials: Cention N, ACTIVA BioActive Restorative, Equia Forte HT Fil, Glass Fill glass carbomer cement (GCP), and Fuji II LC. Vickers microhardness test were used to measure surface hardness. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM/EDS) was used to determine the characterization of the microstructures and elemental analysis of the materials. These measurements were repeated after thermal aging. One-Way ANOVA test, Bonferroni test and the Games-Howell test was used for data analysis. The significance level was accepted as 0.05. RESULTS: Cention N had the highest vickers microhardness value before thermal cycle. The highest fluoride ion ratio among the materials before thermal aging was detected in the Equia Forte HT Fil and Fuji II LC groups. While a decrease in fluorideF ion was detected in all groups except the Cention N group after thermal aging. It is observed that ACTIVA BioActive Restorative has a more microporous and rougher surface in the scanning electron microscopy image after the thermal cycle than in the image before the thermal cycle. CONCLUSIONS: The chemical properties of the materials and the properties of the filler particles may be related to the differences in the mechanical properties, surface characterizations and ion releases of the materials Thermal aging affected the microhardness, surface characteristics and elemental mass ratios of the studied materials. Alkasite bioactive materials are more similar to composite restorative materials and show better mechanical properties than other materials, but do not have the same effect on fluoride release. CLINICAL RELEVANCE: Most of the bioactive materials showed a decrease in the fluoride ion ratio after thermal aging, while no difference was found in the ion exchange of alkasite materials. Material selection should be made more carefully in caries-active individuals whose fluoride release is clinically important.

Effect of combining aminomethacrylate and fluoride against erosive and abrasive challenges on enamel and dentin.

This study evaluated the effect of solutions containing aminomethacrylate copolymer (AA) and sodium fluoride (F; 225 ppm F-) or fluoride plus stannous chloride (FSn; 225 ppm F-, 800 ppm Sn2+) against enamel and dentin erosion/abrasion. Solutions F, FSn, AA, F+AA, FSn+AA, and deionized water as negative control were tested. Bovine enamel and dentin specimens (n = 13/solution/substrate) underwent a set of erosion-abrasion cycles (0.3% citric acid [5 min, 4×/day], human saliva [1 h, 4×/day], brushing [15 s, 2×/day], and treatments [2 min, 2×/day]) for each of five days. Initial enamel erosion was evaluated using Knoop microhardness after the first and second acid challenge on day 1, and surface loss with profilometry after day 5. KOH-soluble fluoride was assessed. Data were analyzed with ANOVA/Tukey tests. The combination of fluoride and AA resulted in higher protection against enamel erosion, whereas this was not the case for the combination of AA and FSn. All treatments protected against enamel and dentin loss. The lowest surface loss values were observed with F+AA and FSn+AA. The polymer did not significantly influence the KOH-soluble fluoride formation on enamel/dentin specimens. The aminomethacrylate copolymer effectively enhanced the efficacy of sodium fluoride against initial erosion and improved the control of enamel and dentin wear of F and FSn solutions.

Crucial textural properties of braised pork to evaluate the oral mastication behavior and its water distribution to influence tenderness.

The complex composition of braised pork, including lean meat, pigskin, and fat, makes it difficult for sensory evaluation of its texture properties. This study investigated the correlation between sensory texture attributes and physicochemical properties to achieve an objective and comprehensive evaluation of the texture of braised pork. Sensory analysis demonstrated that the overall texture acceptability of braised pork was significantly and negatively influenced by sensory texture attributes (including sensory hardness, chewiness, and toughness), while it was positively impacted by sensory adhesiveness, softness, and juiciness. Shear force and texture profile analysis (TPA) variables, reflecting mastication behavior, were used to characterize the textural properties of braised pork. They were closely related to water distribution, with a higher proportion of immobilized water (P21), indicating a higher water holding capacity and a more tender texture. Correlation analysis between sensory texture attributes and physicochemical properties through partial least squares regression further revealed significant associations between shear force, TPA variables, and sensory texture attributes. Moreover, the proportion of immobilized water (P21) significantly and negatively affected sensory hardness and chewiness, whereas the proportion of free water (P22) significantly influenced sensory toughness. Sensory texture attributes could be well predicted by the physicochemical properties by projecting test samples onto calibration models established by known samples. Therefore, a combination of sensory and instrumental measures can reliably reflect the texture properties of braised pork. PRACTICAL APPLICATION: The combination of sensory and instrumental methods is an effective strategy to accurately and objectively evaluate the texture properties of braised pork, which overcomes the limitations caused by the complexity of the composition and texture traits of braised pork. The accurate evaluation and standardization of texture properties is an important premise for the repeatable and stable cooking of traditional braised pork. Furthermore, this research method and findings can also be applied to guide the procedural optimization of smart appliances (e.g., induction cookers) for cooking braised pork.

Edible Ultralong Organic Phosphorescent Excipient for Afterglow Visualizing the Quality of Tablets.

Stimuli-responsive ultralong organic phosphorescence (UOP) materials that in response to external factors such as light, heat, and atmosphere have raised a tremendous research interest in fields of optoelectronics, anticounterfeiting labeling, biosensing, and bioimaging. However, for practical applications in life and health fields, some fundamental requirements such as biocompatibility and biodegradability are still challenging for conventional inorganic and aromatic-based stimuli-responsive UOP systems. Herein, an edible excipient, sodium carboxymethyl cellulose (SCC), of which UOP properties exhibit intrinsically multistimuli responses to excited wavelength, pressure, and moisture, is reported. Impressively, as a UOP probe, SCC enables nondestructive detection of hardness with superb contrast (signal-to-background ratio up to 120), while exhibiting a response sensitivity to moisture that is more than 5.0 times higher than that observed in conventional fluorescence. Additionally, its applicability for hardness monitoring and high-moisture warning for tablets containing a moisture-sensitive drug, with the quality of the drug being determinable through the naked-eye visible UOP, is demonstrated. This work not only elucidates the reason for stimulative corresponding properties in SCC but also makes a major step forward in extending the potential applications of stimuli-responsive UOP materials in manufacturing high-quality and safe medicine.