Fine-tuning the element dose in nanoparticle synthesis is the critical factor determining nanoparticle's impact on plant growth.

This study elucidates the impact of element dose during nanoparticle (NPs) synthesis on plant growth indices. Novel NPs containing two essential micro-nutrients, zinc (Zn) and manganese (Mn), were co-doped on cerium oxide (CeO2) (ZnMnCe) with different ratios (1, 2, and 3%). The synthesized NPs were characterized by advanced analytical techniques (EDX, TEM, SEM, XPS, and XRD) and hydroponically applied to barley (Hordeum vulgare L.). The impact of ZnMnCe NPs on growth indices and plant nutrients was examined. SEM, HRTEM, and confocal microscopy were used to show the morphological and structural influences of ZnMnCe NPs. Results showed that the plant growth indices (root/leaf length, chlorophyll fluorescence, pigmentation, and biomass) were remarkably improved with a 1% Mn/Zn addition. Conversely, growth retardation, cell membrane damage, root morphology deformation, and genotoxicity were apparent by 3% of Mn/Zn addition. Overall, a significant improvement in growth was revealed when Mn and Zn were included at 1%. However, increasing concentrations (2% and 3%) impaired the growth. These results show that the element ratio used in NPs synthesis is essential in the plant's physiological response. Precise adjustment of element dosage during NPs synthesis determines whether the NPs are beneficial or harmful. This must be well-balanced for nanofertilizer production and plant applications.

The effect of surface treatment and thermal aging on the bonding of clear aligner attachments to provisional resin-based material: shear bond strength analysis.

Objectives: The aim of this study is to evaluate the effect of different surface treatments on the shear bond strength (SBS) of clear aligner attachments bonded to Bis-acryl provisional crowns. Methods: 120 cylindrical bisacrylic composite material (ProTemp type) specimens were prepared and divided into six groups (n = 20) based on surface treatment, control: (no treatment); super coarse grit diamond bur, carbide bur, alumina-blasting, non-thermal plasma treatment, and Er:YAG laser treatment. The features of treated surfaces were examined using scanning electron microscopy (SEM). A flowable composite resin (Transbond XT; 3M Unitek) was bonded to the specimens forming the attachment. Half of specimens were subjected to thermal cycling (5,000 cycles). SBS was measured before and after thermal cycling. Each specimen was loaded at the attachment/resin interface at a speed of 0.5 mm/min until failure. The nature of the failure was analyzed using the composite remnants index (CRI). Two-way ANOVA and Tukey HSD were used for data analysis α = 0.5. For CRI scores analysis, Kruskal-Wallis test and Dunn's multiple comparison were used as post-hoc test. Results: SEM analysis showed that all surface treatments altered surface properties and increase surface bonding area. The specimens treated with plasma, Er:YAG laser, and alumina-blasting had higher SBS values before and after thermal cycling. In comparison to control plasma, Er:YAG laser, and alumina-blasting showed a significant increase in SBS (P < 0.001) while carbide and diamond bur groups showed no significant differences (P > 0.05). Thermal cycling significantly decreased the SBS of control, carbide bur, diamond bur, and Er:YAG laser while no significant effect of alumina-blasting and plasma group. Er:YAG laser and plasma groups significantly exhibited more dominance for scores 2 and score 3 and the absence of score 0. Conclusion: Alumina-blasting, Er:YAG laser, or non-thermal plasma surface treatments increased the shear bond strength between clear aligner attachments and resin-based restorations.

Repair strength of 3D-printed denture base resins: Effect of surface treatment and repair material type.

PURPOSE: The aim of the study was to investigate the effect of surface treatment and repair materials on the flexural strength of repaired 3D-printed denture base resins after thermal aging. MATERIALS AND METHODS: Bar-shape specimens (64 × 10 × 3.3 mm) were designed as intact (control) specimens while repair specimens were printed in sections with 2.5 mm space for repair material. Printing was performed with either ASIGA or NextDent denture base material. In each material, one group received no surface treatment, while other repair groups were subjected to one of three surface treatments: (1) monomer application, (2) aluminium oxide particles-abrasion, or (3) both methods (aluminum oxide particles-abrasion and monomer application). Pairs were fixed in a customized mold then repaired with either autopolymerizing acrylic resin or flowable composite (n = 9). Repaired specimens were incubated for 48 h at 37°C in distilled water and then subjected to thermal cycling (5000 cycles). A 3-point bending test was used to evaluate the flexural strength using a universal testing machine, and mode of failure determined followed by fractured surface analysis using scanning electron microscope. Data were analyzed using ANOVA and post hoc Tukey test (α = 0.05). RESULTS: Both resin materials showed a significant decrease in the flexural strength of repaired specimens when compared to control ones (p < 0.001). Groups with no surface treatment had significantly lower flexural strength than those with surface treatment (p < 0.001). Groups treated with monomer application, and with aluminum oxide particles abrasion plus monomer application had similar flexural strength values (p > 0.05), which were higher than those treated with aluminum oxide particles abrasion alone (p < 0.001). Specimens repaired with composite resin showed higher flexural strength than those repaired with auto-polymerized resin (p < 0.05) however, specimens treated with aluminum oxide particles abrasion alone had similar values for both repair materials (p = 0.95). Adhesive failure was dominant in all repaired groups with auto-polymerized while cohesive and mixed were dominant with composite repair groups. CONCLUSION: Surface treatment improved the repair strength of 3D-printed denture base resins. Using composite resin for repair shows better strength with dominant cohesive and mixed failure suggesting that surface treatment and composite repair are suitable procedures for 3D-printed denture base repair.

A crosstalk between 'osteocyte lacunal-canalicular system' and metabolism.

Considering the importance, bone physiology has long been studied to understand what systematic and cellular impact its cells and functions have. Exploring more questions is a substantially solid way to improve the understanding of bone physiological functions in/out sides. In adult bone, osteocytes (Ots) form about 95% of bone cells and live the longest lifespan inside their mineralized surroundings. Ots are the endocrine cells and originate from blood vessel's endothelial cells. In this work, we discussed the vital role of the "Ots". To determine the association between osteocytes' network with metabolic parameters in healthy mice, the experiments were performed on ten (10) adult C57BL6 male mice. Fasting blood and bone samples were collected weekly from mice for measurement of metabolic parameters and bone morphology. Scanning electron microscopy (SEM) revealed a 2D fine morphology of the bone which indicates a strong functional interconnection with bone nano/micro, and macro components of the organs. The long-branched canaliculi look like neurocytes in structure. The morphology and quantitative measurements of the osteocyte lacunal-canalicular system showed its wide spectrum spatial resolution of the positive and negative relationship within this system or metabolite parameters, confirming a strong cross connection between osteocyte lacunal-canalicular system and metabolism. We believe that the findings of this study can deliver a strategy about the potential roles of metabolic relation among osteocytes, insulin, and lipid in management of bone and metabolic diseases.

A Comparative In Vitro Physicochemical Analysis of Resin Infiltrants Doped With Bioactive Glasses.

Objective This study aimed to investigate the longevity and effectiveness of bioactive glass (BAG)-based dental resin infiltrants. Materials and methods The three types of BAG - 45S5 bioglass (RIS), boron-substituted (RIB), and fluoride-substituted (RIF) - were incorporated with photoinitiated dimethacrylate monomers to create experimental resin infiltrants. ICON® (CN; DMG-America, Ridgefield Park, NJ) and pure resin (PR) were used as control groups in this study. Disc-shaped samples were prepared for the experimental and control groups. The samples were challenged with the pH cycle and immersed in the artificial saliva for 30 days. On Day 0 and Day 30, the pH cycle and artificial saliva immersion, Vicker's microhardness, surface roughness, and surface morphology were investigated. Results The RIF group's disc samples showed the highest Vicker's microhardness values (78.20 ±0.06) on Day 30 of artificial saliva immersion, whereas the CN group's values were the lowest (55.99 ±0.24). Following the pH cycling, the RIF displayed the highest hardness (64.15 ±1.89) whereas the CN group's values were the lowest (33.47 ±1.28). Regarding surface roughness, on Day 30, the RIB resin group exhibited the highest (1.14 ±0.001 µm). In contrast, the CN resin showed the lowest (1.07 ±0.06 µm) values, while immersed in the artificial saliva solution. In the same duration of time, in the pH cycling solution, PR showed the least (0.85 ±0.89 µm), while RIF showed the highest roughness value (0.94 ±0.54 µm). Morphological analysis revealed that following the artificial saliva immersion, the RIB, CN, and PR exhibited smoother surfaces compared to the RIS and RIF groups. However, when immersed in the pH cycling solution, RIB and RIF showed more resistance against acid attack. Conclusions Our results revealed that the experimental resin groups performed much better than the commercial resin infiltrants following artificial saliva and pH cycling challenges.

Bionanocomposites comprising mesoporous metal organic framework (ZIF-8) phytofabricated with Allium sativum as alternative nanomaterials to combat antimicrobial drug resistance.

Green nanotechnology is one of the most expanding fields that provides numerous novel nanoparticle drug formulations with enhanced bioactivity performance. This study aims to synthesize mesoporous metal organic framework (ZIF-8) phytofabricated with the herb Allium sativum (As) as an indicator system for its antibacterial and antifungal impact. The successful synthesis of ZIF-8 as nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning coupled with energy-dispersive X-ray spectroscopy and transmission electron microscopy (SEM-EDX and TEM) that showed the textural retainment of ZIF-8 on composite formation with A. sativum. The nanocomposite, A. sativum extract, and ZIF-8 were subjected to antimicrobial assays against Shigella flexneri, Candida albicans, and Candida parapsilosis. The comparative results indicated the potential action of nanocomposite against the bacteria and both the Candida sps; however, the antifungal action against the Candida sps was more effective than the bacterium S. flexneri. The findings suggest that plants, being an important component of ecosystems, could be further explored for the novel drug discovery using green nanotechnology to enhance their impact on the drug-resistant pathogens.

Synergistic effect of Silver-Nanodiamond composite as an efficient antibacterial agent against E. coli and S. aureus.

Bacterial antimicrobial resistance (BAMR) seems to pose the greatest threat to public health, food safety, and agriculture in this century. The development of novel efficient antimicrobial agents to combat bacterial infections has become a global issue. Silver nanoparticles (Ag NPs) appeared as a feasible alternative to antibiotics. However, Ag NPs face cost, toxicity, and aggregation issues which limit their antibacterial activity. This work aims to stabilize Ag NPs with enhanced antimicrobial activity at comparatively lower Ag concentrations to prevent bacterial infections. For this purpose, the Ag core was covered with nanodiamonds (NDs). Ag-NDs composite have been synthesized by microplasma technique. TEM analysis confirmed the presence of both Ag and NDs in the Ag-NDs composite. A particle size (∼19 nm) was reported for Ag-NDs at the highest concentration as compared to Ag NPs (∼3 nm). The conduction band of the diamond acted as an extremely strong reducing agent for Ag NPs. The large surface area of NDs stabilized the Ag NPs. A redshift (∼400 nm-406 nm) in UV-visible spectra of the Ag-NDs composite indicated the formation of bigger-sized Ag NPs after incorporating NDs. XRD and LIBS analysis verified the increase in intensity of Ag-NPs by increasing ND concentration. The presence of functional groups including OH, CH, and Ag/Ag2O was confirmed by FTIR. Bacterial inhibition growth appeared to be a dose-dependent process. The minimum inhibition concentration value of Ag-NDs composite at the highest NDs concentration against E. coli (∼ 0.69 µg/ml) and S. aureus (∼44 µg/ml). This is the first study to report the smallest MIC for E. coli (<1 µg/ml). Ag-ND composites emerged to be more efficient than Ag NPs and preferred to be used against BAMR. The enhanced antibacterial activity of the Ag-NDs composite makes it a potential candidate for antibiotics, food products, and pesticides.

Zeolitic Imidazole Framework/Silica Nanocomposite for Targeted Cancer Therapeutics: Comparative Study of Chemo-Drug Cisplatin (CPt) and Green Platinum (GPt) Efficacy.

A chemo-drug such as cisplatin is effective for cancer treatment but remains non-specific, is susceptible to drug resistance, and induces several side effects on organ systems. Zeolitic imidazolate framework-8, a type of MOF, has gained attention, including as a drug delivery method for targeted cancer therapeutics. In this study, ZIF-8/Silica nanocomposite was synthesized using a one-pot hydrothermal technique using the Stober technique. We studied the effect of phyto-synthesized GPt and chemo-drug cisplatin CPt on ZIF-8/Silica for targeted efficacy of cancer therapy. The texture, morphology, and chemical environment of Pt on ZIF-8/Silica were analyzed using different characterization techniques such as XRD, FT-IR, BET, diffuse reflectance spectroscopy, SEM-EDX, TEM, zeta potential, and TGA analysis. The isothermal behavior of CPt and GPt adsorption was investigated using isotherm models like Langmuir, Freundlich, and Temkin isotherm. The adsorption kinetics indicating the adsorption efficiency of GPt and CPt are influenced by the concentration of Pt complex and the adsorption sites of ZIF-8/Silica. A high entrapment efficiency and loading capacity of GPt (86% and 4.3%) and CPt (91% and 4.5%) were evident on ZIF-8/Silica. The nanocomposite showed a pH-sensitive Pt release using a dialysis membrane technique. For instance, a high release of GPt (93%) was observed under pH = 6.6 in 72 h, while the release reduced to 50% at pH 7.4 in 72 h. The anti-cancer activity of nanoformulations was studied in vitro using MCF7 (breast cancer cells) and HFF-1 (human foreskin fibroblast) cells. The findings demonstrated that GPt is as effective as CPt; the EC50 value for MCF7 cells treated with ZIF-8/Silica/Cp/PEG was 94.86 µg/mL, whereas for ZIF-8/Silica/GPt/PEG it was 60.19 µg/mL.

Flexural strength of 3D-printed nanocomposite provisional resins: Impact of SiO2 and ZrO2 nanoparticles and printing orientations in vitro.

PURPOSE: The aim of this study was to investigate and compare the influence of zirconium dioxide nanoparticles (ZrO2 NPs) and silicon dioxide nanoparticles (SiO2 NPs) addition and printing orientation on the flexural strength (FS) of provisional three-dimensional (3D) printing resins undergoing thermal cycling (TC). METHODS: Three dimensional-printed resin (NextDent C&B MFH) was used to fabricate 300 bar-shaped specimens (25 × 2 × 2 mm3 ). The ZrO2 NPs and SiO2 NPs specimens were divided into two groups, then subdivided into three groups, based on the nanoparticle concentration (i.e., 0 wt% (original group), 0.5 wt%, and 1 wt%). Each concentration was printed in three printing orientations (0°, 45°, and 90°). The printed specimens were exposed to 5000 cycles of TC, followed by a three-point bending test to assess the FS. Fracture surface analysis was conducted by using a scanning electron microscope (SEM). For data analysis, ANOVA and Tukey's post hoc were utilized (α = 0.05). RESULTS: Compared to the original material, the addition of ZrO2 NPs and SiO2 NPs had a significantly positive impact on the FS, (P > 0.001). After TC, the FS of the original group decreased significantly and had the lowest value. The highest FS value was observed in 1% ZrO2 NPs at 0°. Regardless of the nanoparticle concentration, the 0° orientation consistently showed a higher FS, compared to the 45° and 90° orientations. At all orientations (i.e., 0°, 45°, and 90°), the FS significantly increased with the addition of NPs, compared with that of the original material (P > 0.001). TC had a significantly negative effect on the FS of the unmodified groups. However, no significant differences existed in FS among the modified groups after TC. CONCLUSION: The addition of SiO2 NPs and ZrO2 NPs increased the FS of the 3D-printed provisional resin. Regardless of the nanoparticle concentration, the 0° orientation had the higher FS. TC had an effect on the original resin, whereas it had no significant effect on the nanoparticle-modified resins. In clinical practice, 3D-printed provisional nanocomposite resins printed at the 0° orientation could be recommended for long-term dental provisional restorations.

Uptake and bioaccumulation of iron oxide nanoparticles (Fe3O4) in barley (Hordeum vulgare L.): effect of particle-size.

Root-to-shoot translocation of nanoparticles (NPs) is a matter of interest due to their possible unprecedented effects on biota. Properties of NPs, such as structure, surface charge or coating, and size, determine their uptake by cells. This study investigates the size effect of iron oxide (Fe3O4) NPs on plant uptake, translocation, and physiology. For this purpose, Fe3O4 NPs having about 10 and 100 nm in average sizes (namely NP10 and NP100) were hydroponically subjected to barley (Hordeum vulgare L.) in different doses (50, 100, and 200 mg/L) at germination (5 days) and seedling (3 weeks) stages. Results revealed that particle size does not significantly influence the seedlings' growth but improves germination. The iron content in root and leaf tissues gradually increased with increasing NP10 and NP100 concentrations, revealing their root-to-shoot translocation. This result was confirmed by vibrating sample magnetometry analysis, where the magnetic signals increased with increasing NP doses. The translocation of NPs enhanced chlorophyll and carotenoid contents, suggesting their contribution to plant pigmentation. On the other hand, catalase activity and H2O2 production were higher in NP10-treated roots compared to NP100-treated ones. Besides, confocal microscopy revealed that NP10 leads to cell membrane damages. These findings showed that Fe3O4 NPs were efficiently taken up by the roots and transported to the leaves regardless of the size factor. However, small-sized Fe3O4 NPs may be more reactive due to their size properties and may cause cell stress and membrane damage. This study may help us better understand the size effect of NPs in nanoparticle-plant interaction.

Preparation of novel S-allyl cysteine chitosan based nanoparticles for use in ischemic brain treatment.

Objective: To enhance the brain bioavailability of S-allyl-l-cysteine (SC) by developing novel S-allyl-l-cysteine chitosan nanoparticles (SC CS NPs) and examining the quantity of SC by developing a novel method of ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in ischemic rat brain treatment. Methods: The ionotropic gelation method was used to develop S-allyl cysteine-loaded CS NPs. The 4-factor, 5-level central composite design was optimized to determine the effect of independent variables, i.e., particle size, polydispersity index (PDI), zeta potential, EE, and loading capacity, together with their characterization, followed by drug release and intranasal permeation to enhance the brain bioavailability and examination of their neurobehavioral and biochemical parameters with their histopathological examination. Results: SC CS NPs were optimized at the particle size of 93.21 ± 3.31 nm (PDI: 0.317 ± 0.003), zeta potential of 44.4 ± 2.93, and drug loading of 41.23 ± 1.97% with an entrapment efficiency of 82.61 ± 4.93% having sustain and controlled release (79.92 ± 3.86%) with great permeation (>80.0%) of SC. SC showed the retention time of 1.021 min and 162.50/73.05 m/z. SC showed good linearity in the range of 5.0-1300.0 ng mL-1, % inter-and-intraday accuracy of 96.00-99.06% and CV of 4.38-4.38%. We observed significant results, i.e., p < 0.001 for improved (AUC)0-24 and Cmax delivered via i.v. and i.n. dose. We also observed the highly significantly observations of SC CS NPs (i.n.) based on their treatment results for the biochemical, neurobehavioral, and histopathological examination in the developed ischemic MCAO brain rat model. Conclusion: The excellent significant role of mucoadhesive CS NPs of SC was proven based on the enhancement in the brain bioavailability of SC via i.n. delivery in rats and easy targeting of the brain for ischemic brain treatment followed by an improvement in neuroprotection based on a very small dose of SC.

Comparative Evaluation of TiO2 Nanoparticle Addition and Postcuring Time on the Flexural Properties and Hardness of Additively Fabricated Denture Base Resins.

Three-dimensionally (3D)-printed fabricated denture bases have shown inferior strength to conventional and subtractively fabricated ones. Several factors could significantly improve the strength of 3D-printed denture base resin, including the addition of nanoparticles and post-curing factors. This study evaluated the effect of TiO2 nanoparticle (TNP) addition and the post-curing time (PCT) on the flexural properties and hardness of three-dimensionally (3D)-printed denture base resins. A total of 360 specimens were fabricated, with 180 specimens from each type of resin. For evaluating the flexural properties, bar-shaped specimens measuring 64 × 10 × 3.3 mm were used, while, for the hardness testing, disc-shaped specimens measuring 15 × 2 mm were employed. The two 3D-printed resins utilized in this study were Asiga (DentaBASE) and NextDent (Vertex Dental B.V). Each resin was modified by adding TNPs at 1% and 2% concentrations, forming two groups and an additional unmodified group. Each group was divided into three subgroups according to the PCT (15, 60, and 90 min). All the specimens were subjected to artificial aging (5000 cycles), followed by testing of the flexural strength and elastic modulus using a universal testing machine, and the hardness using the Vickers hardness test. A three-way ANOVA was used for the data analysis, and a post hoc Tukey's test was used for the pairwise comparisons (α = 0.05). Scanning electron microscopy (SEM) was used for the fracture surface analysis. The addition of the TNPs increased the flexural strength in comparison to the unmodified groups (p < 0.001), while there was no significant difference in the elastic modulus and hardness with the 1% TNP concentration. Among the TNP groups, the 2% TNP concentration significantly decreased the elastic modulus and hardness (p < 0.001). The SEM showed a homogenous distribution of the TNPs, and the more irregular fracture surface displayed ductile fractures. The PCT significantly increased the flexural strength, elastic modulus, and hardness (p < 0.001), and this increase was time-dependent. The three-way ANOVA results revealed a significant difference between the material types, TNP concentrations, and PCT interactions (p < 0.001). Both concentrations of the TNPs increased the flexural strength, while the 2% TNP concentration decreased the elastic modulus and hardness of the 3D-printed nanocomposites. The flexural strength and hardness increased as the PCT increased. The material type, TNP concentration, and PCT are important factors that affect the strength of 3D-printed nanocomposites and could improve their mechanical performance.

Influence of denture brushing on the surface properties and color stability of CAD-CAM, thermoformed, and conventionally fabricated denture base resins.

PURPOSE: To assess the influence of denture brushing on the surface roughness, hardness, and color stability of conventional, thermoformed, and CAD-CAM denture base materials. MATERIALS AND METHODS: Seven different denture base materials were included in this study; conventional heat-polymerized acrylic resin (PMMA) served as control, polyamide, acetal, two categories of milled acrylic discs (AvaDent and IvoCad), and two categories of 3D-printed resins (NextDent and FormLabs). The specimens were constructed according to manufacturers' instructions and then subjected to simulated brushing (20,000 cycles). According to the brushing method, the specimens were split into three groups, no brushing, brushing with water, and brushing with toothpaste. Surface roughness, hardness, and color change were evaluated before and after brushing. Collected data were analyzed using ANOVA, and post-hoc Tukey's tests (α = 0.05). RESULTS: A significant difference was noted between the surface roughness of the tested materials before and after denture brushing (p < 0.05), and milled resin showed the least Ra values. Denture brushing with water significantly increased the Ra of PMMA (p = 0.004) and IvoCad (p = 0.032), while brushing using toothpaste did not show a significant increase. The brushing protocols did not alter the hardness of tested materials except that of PMMA (p = 0.001). The color stability of the tested materials showed comparable results with both brushing protocols. CONCLUSION: The tested properties showed variations between the types of denture base resins. Hardness and color stability of CAD-CAM and thermoformed denture base resins were not altered by denture brushing and showed comparable results with both brushing methods. Surface roughness was the only property that showed alteration after denture brushing.

Synthesis and analyses of injectable fluoridated-bioactive glass hydrogel for dental root canal sealing.

This study aimed to synthesize fluoride-doped bioactive glass (F-BG) based thermo-sensitive injectable hydrogel for endodontic applications. The structural and phase analyses were done with Fourier Transform Infrared spectroscopy and X-ray Diffraction, respectively. The setting time of prepared injectable was investigated at 21°C (in the presence and absence of an ultrasonic scalar) and at 37°C. Flowability was tested according to ISO-6876:2012 specifications, whereas injectability was checked by extrusion method using 21-, 22-, and 23-gauge needles. The in vitro bio-adhesion and push-out bond strength were studied on days 7 and 90 and compared with the commercially available TotalFill®. The ion release profile was analyzed for up to 30 days with Inductively Coupled Plasma Optical Emission Spectroscopy. The fluoride release analysis was conducted periodically for up to 21 days in deionized water and artificial saliva using an ion-selective electrode. The final setting time at 21°C, 21°C+ultrasonic scalar, and 37°C were 38.66±3.21, 29.12±1.23, and 32±3.46 min, respectively. The flowability was 25±3.94 mm, and the injectability coefficient was ≥70.3 for 22, 21, and 57% in a 23-gauge needle. Fluoride release in deionized water was found to be significantly higher than in artificial saliva and increased with time. A significant difference in bond strength was found between days 7 and 90, where the strength was increased, and a new apatite layer was formed on the tooth surface. A rapid release of calcium, phosphate, and silicon ions was seen initially, whereby the continuous release of these ions was observed for up to 30 days. The prepared F-BG injectable hydrogel has shown promising results and has the potential to be used as an endodontic sealer.

Mining the nanotube-forming Bacillus amyloliquefaciens MR14M3 genome for determining anti-Candida auris and anti-Candida albicans potential by pathogenicity and comparative genomics analysis.

There is a global health concern associated with the emergence of the multidrug-resistant (MDR) fungus Candida auris, which has significant mortality rates. Finding innovative and distinctive anti-Candida compounds is essential for treating infections caused by MDR C. auris. A bacterial strain with anti-Candida activity was isolated and identified using 16 S rRNA gene sequencing. The whole genome was sequenced to identify biosynthesis-related gene clusters. The pathogenicity and cytotoxicity of the isolate were analyzed in Candida and HFF-1 cell lines, respectively. This study set out to show that whole-genome sequencing, cytotoxicity testing, and pathogenicity analysis combined with genome mining and comparative genomics can successfully identify biosynthesis-related gene clusters in native bacterial isolates that encode antifungal natural compounds active against Candida albicans and C. auris. The native isolate MR14M3 has the ability to inhibit C. auris (zone of inhibition 25 mm) and C. albicans (zone of inhibition 25 mm). The 16 S rRNA gene sequence of MR14M3 aligned with Bacillus amyloliquefaciens with similarity (100%). Bacillus amyloliquefaciens MR14M3 establishes bridges of intercellular nanotubes (L 258.56 ± 35.83 nm; W 25.32 ± 6.09 nm) connecting neighboring cells. Candida cell size was reduced significantly, and crushed phenotypes were observed upon treatment with the defused metabolites of B. amyloliquefaciens MR14M3. Furthermore, the pathogenicity of B. amyloliquefaciens MR14M3 on Candida cells was observed through cell membrane disruption and lysed yeast cells. The whole-genome alignment of the MR14M3 genome (3981,643 bp) using 100 genes confirmed its affiliation with Bacillus amyloliquefaciens. Genome mining analysis revealed that MR14M3-coded secondary metabolites are involved in the biosynthesis of polyketides (PKs) and nonribosomal peptide synthases (NRPSs), including 11 biosynthesis-related gene clusters with one hundred percent similarity. Highly conserved biosynthesis-related gene clusters with anti-C. albicans and anti-C. auris potentials and cytotoxic-free activity of B. amyloliquefaciens MR14M3 proposes the utilization of Bacillus amyloliquefaciens MR14M3 as a biofactory for an anti-Candida auris and anti-C. albicans compound synthesizer.

Analyses of Experimental Dental Adhesives Based on Zirconia/Silver Phosphate Nanoparticles.

This study aimed to evaluate the incorporation of zirconia/silver phosphate nanoparticles to develop experimental dental adhesives and to measure their physical and mechanical properties. The nanoparticles were synthesized by the sonication method, and the phase purity, morphological pattern, and antibacterial properties with Staphylococcus aureus and Pseudomonas aeruginosa were assessed. The silanized nanoparticles were incorporated (0, 0.15, 0.25, and 0.5 wt.%) into the photoactivated dimethacrylate resins. The degree of conversion (DC) was assessed, followed by the micro-hardness and flexural strength/modulus test. Long-term color stability was investigated. The bond strength with the dentin surface was conducted on days 1 and 30. The transmission electron microscopy and X-ray diffractogram confirmed the nano-structure and phase purity of the particles. The nanoparticles showed antibacterial activities against both strains and inhibited biofilm formation. The DC range of the experimental groups was 55-66%. The micro-hardness and flexural strength increased with the concentration of nanoparticles in the resin. The 0.5 wt.% group showed significantly high micro-hardness values, whereas a non-significant difference was observed between the experimental groups for flexural strength. The bond strength was higher on day 1 than on day 30, and a significant difference was observed between the two periods. At day 30, the 0.5 wt.% showed significantly higher values compared to other groups. Long-term color stability was observed for all the samples. The experimental adhesives showed promising results and potential to be used for clinical applications. However, further investigations such as antibacterial, penetration depth, and cytocompatibility are required.

The Toothbrushing Effects on Surface Properties and Color Stability of CAD/CAM and Pressable Ceramic Fixed Restorations-An In Vitro Study.

Pressable ceramic restorations have been introduced and investigated, and found comparable to CAD/CAM ceramic in terms of mechanical properties; however, the effect of toothbrushing on the pressable ceramic has not been thoroughly investigated. The objective of the current study was to assess the effect of artificial toothbrushing simulation on the surface roughness, microhardness, and color stability of different ceramic materials. Three lithium disilicate-based ceramics (IPS Emax CAD [EC], IPS Emax Press [EP]; (Ivoclar Vivadent AG), and LiSi Press [LP] (GC Corp, Tokyo, Japan)) were examined. For each ceramic material, eight bar-shaped specimens were prepared and subjected to 10,000 brushing cycles. Surface roughness, microhardness, and color stability (∆E) were measured before and after brushing. Scanning electron microscopy (SEM) was used for surface profile analysis. The results were analyzed using one-way ANOVA, Tukey's post hoc test, and paired sample t-test α = 0.05. The findings revealed a non-significant decrease in the surface roughness of EC, EP, and LP groups (p > 0.05), and both LP and EP have the lowest surface roughness values (0.64 ± 0.13, 0.64 ± 0.08 µm) after brushing, respectively. Toothbrushing showed a decrease in the microhardness of the three groups: EC and LP, p < 0.001; EP, p = 0.012). EP showed the lowest hardness value after brushing (862.45 ± 273.83). No significant changes (∆E) were observed in all groups (p > 0.05); however, the EC group was found to be considerably affected by color changes, in comparison to the EC and LP groups. Toothbrushing had no effect on surface roughness and color stability of all tested materials, but it decreased the microhardness. Material type, surface treatments, and glazing of ceramic materials contributed to the surface changes in the ceramic materials, necessitating further investigations in terms of the toothbrushing effect with different glazing as variables.

Effect of Different Scaling Methods on the Surface Topography of Different CAD/CAM Ceramic Compositions.

This study evaluated the effect of ultrasonic and manual scaling using different scaler materials on the surface topography of computer-aided designing and computer-aided manufacturing (CAD/CAM) ceramic compositions. After scaling with manual and ultrasonic scalers, the surface properties of four classes of CAD/CAM ceramic discs: lithium disilicate (IPE), leucite-reinforced (IPS), advanced lithium disilicate (CT), and zirconia-reinforced lithium silicate (CD) of 1.5 mm thickness were evaluated. Surface roughness was measured before and after treatment, and scanning electron microscopy was used to evaluate the surface topography following the performed scaling procedures. Two-way ANOVA was conducted to assess the association of the ceramic material and scaling method with the surface roughness. There was a significant difference in the surface roughness between the ceramic materials subjected to different scaling methods (p < 0.001). Post-hoc analyses revealed significant differences between all groups except for IPE and IPS where no significant differences were detected between them. CD showed the highest surface roughness values, while CT showed the lowest surface roughness values for the control specimens and after exposure to different scaling methods. Moreover, the specimens subjected to ultrasonic scaling displayed the highest roughness values, while the least surface roughness was noted with the plastic scaling method.

Effect of Denture Disinfectants on the Mechanical Performance of 3D-Printed Denture Base Materials.

Denture care and maintenance are necessary for both denture longevity and underlying tissue health. However, the effects of disinfectants on the strength of 3D-printed denture base resins are unclear. Herein, distilled water (DW), effervescent tablet, and sodium hypochlorite (NaOCl) immersion solutions were used to investigate the flexural properties and hardness of two 3D-printed resins (NextDent and FormLabs) compared with a heat-polymerized resin. The flexural strength and elastic modulus were investigated using the three-point bending test and Vickers hardness test before (baseline) immersion and 180 days after immersion. The data were analyzed using ANOVA and Tukey's post hoc test (α = 0.05), and further verified by using electron microscopy and infrared spectroscopy. The flexural strength of all the materials decreased after solution immersion (p < 0.001). The effervescent tablet and NaOCl immersion reduced the flexural strength (p < 0.001), with the lowest values recorded with the NaOCl immersion. The elastic modulus did not significantly differ between the baseline and after the DW immersion (p > 0.05), but significantly decreased after the effervescent tablet and NaOCl immersion (p < 0.001). The hardness significantly decreased after immersion in all the solutions (p < 0.001). The immersion of the heat-polymerized and 3D-printed resins in the DW and disinfectant solutions decreased the flexural properties and hardness.