Multiple Pairwise Comparisons Research Articles

Static friction, surface roughness, and antibacterial activity of orthodontic brackets coated with silver and silver chitosan nanoparticles

To determine the effect of silver and silver chitosan nanocoatings on monocrystalline ceramic, polycrystalline ceramic, and metallic brackets regarding friction, roughness, and antibacterial effect against Streptococcus mutans. A total of 99 upper right premolar brackets with a 0.022 × 0.025 -inch slot were divided into three groups, each 33 according to coating material; the non-coated group, silver nanoparticles (AgNPs), and silver chitosan nanoparticles (Ag-CsNPs) groups. Each group was equally subdivided into the following three subgroups regarding bracket materials: monocrystalline ceramic, polycrystalline ceramic, and metallic brackets. A universal testing machine determined static friction on a custom-made acrylic jig. Then a profilometer machine was used to collect roughness data, and finally, the anti-cariogenic effect was measured with the disc diffusion technique's "minimum zone of inhibition" against Streptococcus mutans. Two-way ANOVA was used to compare data between groups and subgroups, followed by the Bonferroni test for multiple pair-wise comparisons. The nanocoating effect on ceramic brackets' static friction was non-significant. The AgNPs and Ag-CsNPs coated metallic group revealed a significant increase in static friction-a significant effect of the nanocoating in the surface roughness of monocrystalline and polycrystalline ceramic brackets. A significant favorable effect of AgNPs and Ag-CsNPs against Streptococcus mutans was observed. AgNPs and Ag-CsNPs coats are unsuitable for decreasing friction in metallic brackets or improving roughness in polycrystalline ceramic brackets. Nano coating can improve roughness in monocrystalline ceramic brackets. Coating brackets with AgNPs and Ag-CsNPs has a tremendous antibacterial effect on Streptococcus mutans, a substantial factor in the incidence of dental caries.

TestDimorph: An R package for analysis of interpopulation sexual dimorphism differences using summary statistics.

The degree of sexual dimorphism in certain traits between males and females differ from one sample to another. Although trait differences by sex are often reported in bioanthropological research, few studies test for statistical significance or make raw data available. TestDimorph is the first R package dedicated to testing and comparing the degree of sexual dimorphism among different samples by leveraging summary statistics. We provide two approaches of analysis of inter-sample differences in degree of sexual dimorphism: univariate and multivariate for two or more samples. The methods follow upon publications primarily from the AJBA. Within-sex size variability between samples is compared using one-way ANOVA followed by control for multiple pairwise comparisons. In addition, we compute the overlapping area between the density functions of two normal distributions from the mixture intersection index or the non-overlapping area using the dissimilarity index as well as Hedges' g with inferential support using the 95% confidence interval. Finally, we use a multivariate analysis of differences in patterning of sexual dimorphism between samples. We demonstrate various results from applying TestDimorph functions to data supplied with the package. The package has many features including functionality for working with summary statistics, simulating data from summary statistics, and the extraction of summary statistics from raw data, so that the entire analysis can be performed through the package.

Effects of the internal contact surfaces of dental implants on screw loosening: A 3-dimensional finite element analysis

Statement of problemThe effects of the internal contact surfaces of dental implants on screw loosening have yet to be investigated. PurposeThe purpose of this 3-dimensional finite element analysis (FEA) study was to evaluate and compare the mechanical effects of the abutment implant angle (θ), the abutment screw head diameter (D), and the abutment screw length (L) on screw loosening. Material and methodsA total of 27 models presenting various mechanical scenarios were built by using combinations of 3 different θ (30 degrees, 45 degrees, and 60 degrees), D (2.65 mm, 2.75 mm, and 2.85 mm), and L (4 mm, 5 mm, and 6 mm). In FEA, a static test with a 200-N force inclined 30 degrees in the implant axial direction was applied to the upper surface of the abutment to evaluate and compare the maximum von Mises stresses of the implant components and the maximum total deformation in all models. In addition, modal analysis was applied to identify the natural frequencies in all models under free (unforced) vibration, and a Kruskal-Wallis statistical test (α=.05) was performed, followed by multiple pairwise comparisons by using the Dunn test. ResultsThe Kruskal-Wallis test found a significant influence of the θ on implant stress, total deformation, and natural frequency (P<.001). For example, increasing the θ from 30 degrees to 45 degrees and 60 degrees can considerably reduce the model’s natural frequencies to 18% and 26%, respectively. Similarly, the test underscored the significant impact of the D on both abutment screw stress and abutment stress (P=.010 and P=.002, respectively). However, the L appeared to have no significant effect on any of the dependent variables (P>.05). ConclusionsThe θ and the D significantly influenced the stresses of dental implant components, total deformation, and natural frequency of the model, which may impact the mechanical stability of the screw joint. However, the L does not appear to affect these values significantly.

Assessment of awake bruxism in undergraduate students, using Ecological Momentary Assessment, through WhatsApp

This study assessed awake bruxism (AB) in undergraduate students using WhatsApp and examined the association of this behavior with quality of life and anxiety. The sample was composed of 36 healthy young adults of both genders, with an average age of 20.74 years. AB behaviors (teeth contact, teeth clenching, teeth grinding and mandible bracing) and relaxed jaw muscles were reported with Ecological Momentary Assessment, through WhatsApp, 15 times a day, for 7 days, between 8:00 am and 7:00 pm. Quality of Life (QoL) and anxiety were assessed using the SF-36 and GAD-7 questionnaires, respectively. The Mann-Whitney U non-parametric, Pearson and Spearman correlation and Pairwise non-parametric multiple comparisons 2- to-2 tests were used. The frequency of AB was 40.7%. The most frequent AB behavior was teeth contact (23.1%). Higher frequency of AB occurred on weekdays (42.3%) compared to the weekend (35.5%) (p&lt;0.05). There was a negative correlation of AB behaviors and mandible bracing with the QoL - emotional aspects domain (p&lt;0.05) and positive correlation of mandible bracing with anxiety (p&lt;0.01). There was no difference between genders for QoL, anxiety and AB behaviors (p&gt;0.05). This study highlights the importance of AB and anxiety control to improve undergraduate students’ quality of life.

Barriers to Effective Cancer Pain Management, Comparing the Perspectives of Physicians, Nurses, and Patients

BackgroundPain associated with cancer is one of the most significant concerns for patients, families, and health care providers. Various barriers may hinder optimal pain management. AimThe study was conducted in specialized cancer center in Jordan and aimed to explore the barriers to effective cancer pain management from the perspectives of physicians, nurses, and patients. MethodsA quantitative descriptive cross-sectional design was used, with a total sample of 185 participants (55 Physicians, 70 Nurses, and 60 Patients) who completed a demographic datasheet and the Arabic-Barrier Questionnaire II (BQII). ResultsThe overall BQII of patient score was 2.4 (standard deviation [SD] = 0.7). The harmful effects of pain medications were the highest barrier 2.7 (SD = 1.0), followed by the physiologic effect 2.4 (SD = 0.9), and the communication 2.4 (SD = 1.1) subscales. Nurses and physicians reported an overall BQII of 1.9 (SD = 1.1) and 1.8 (SD = 0.9), respectively. One-way analysis of variance showed that the perspectives of patients, physicians, and nurses differed significantly in the overall BQII F(2, 182) = 6.81, p < .01, communication F(2, 182) = 10.55, p < .01, and harmful effects F(2, 182) = 7.26, p < .01. Multiple pairwise comparisons also showed that the patients significantly perceived higher communication barriers, more concerns of analgesic harmful effects, and higher overall barriers than nurses and physicians. ConclusionsSignificant differences were found in the perspectives of patients, physicians, and nurses toward pain management barriers in the overall barriers, communication, and harmful effect. It is recommended to develop awareness programs for patients about pain management, barriers, use of analgesia, and communication. Nurses and physicians are advised to discuss mutual concerns and pay more attention to overcoming patient concerns.

Brachytherapy for targeting the immune system in cervical cancer patients

BackgroundNew combinations based on standard therapeutic modalities and immunotherapy require understanding the immunomodulatory properties of traditional treatments. The objective was to evaluate the impact of brachytherapy (BT) on the immune system of cervical cancer and to identify the best modality, High-dose-rate brachytherapy (HDR-BT) vs. Pulsed-dose-rate (PDR-BT), to target it.MethodsNineteen patients enrolled in a prospective study received chemoradiation (CRT) and subsequently HDR-BT or PDR-BT. Peripheral blood samples were obtained for immunophenotyping analysis by flow-cytometry before CRT, BT, and two and four weeks after BT. The Friedman one-way ANOVA, Conover post hoc test, and the Wilcoxon signed-rank test were used to compare changes in cell populations at different periods, perform multiple pairwise comparisons and assess differences between treatment groups (PDR and HDR).ResultsNatural killer cells (NKs) were the best target for BT. Patients receiving HDR-BT achieved significantly higher values ​​and longer time of the CD56dimCD16 + NK cells with greater cytotoxic capacity than the PDR-BT group, which presented their highest elevation of CD56-CD16 + NK cells. Furthermore, both BT modalities were associated with an increase in myeloid-derived suppressor cells (MDSCs), related to a worse clinical prognosis. However, there was a decrease in the percentage of CD4 + CD25 + Foxp3 + CD45RA + regulatory T cells (Tregs) in patients receiving HDR-BT, although there were no significant differences between BT.ConclusionsImmune biomarkers are important predictive determinants in cervical cancer. Higher cytotoxic NK cells and a trend toward lower values of Tregs might support the use of HDR-BT to the detriment of PDR-BT and help develop effective combinations with immunotherapy.

Parallel endodontic education via social media: An exploratory survey study.

There is insufficient research to evaluate social media's influence on endodontic education. Therefore, this study assessed the percentage of students utilising Facebook in their education and the factors influencing their engagement. A survey was conducted on dental students, interns and dentists undertaking specialist programmes. Categorical data were analysed using Fisher's Exact test and multiple pairwise comparisons. The significance level was set at p < 0.05. Responses were received from 801 participants, with 98.4% using Facebook for endodontic knowledge. Although most students knew that scientific evidence is not always provided, they still deemed such information valuable as it was a practical demonstration of clinical cases. Most students turn to Facebook for endodontic education to compensate for the gap between their academic education and clinical practice. The utilisation of social media for education can be a concerning phenomenon and should not be ignored by academic institutes.

Whole-genome sequencing reveals fine-scale environment-associated divergence near the range limits of a temperate reef fish.

Environmental variation is increasingly recognized as an important driver of diversity in marine species despite the lack of physical barriers to dispersal and the presence of pelagic stages in many taxa. A robust understanding of the genomic and ecological processes involved in structuring populations is lacking for most marine species, often hindering management and conservation action. Cunner (Tautogolabrus adspersus) is a temperate reef fish with both pelagic early life-history stages and strong site-associated homing as adults; the species is also of interest for use as a cleaner fish in salmonid aquaculture in Atlantic Canada. We aimed to characterize genomic and geographic differentiation of cunner in the Northwest Atlantic. To achieve this, a chromosome-level genome assembly for cunner was produced and used to characterize spatial population structure throughout Atlantic Canada using whole-genome sequencing. The genome assembly spanned 0.72 Gbp and 24 chromosomes; whole-genome sequencing of 803 individuals from 20 locations from Newfoundland to New Jersey identified approximately 11 million genetic variants. Principal component analysis revealed four regional Atlantic Canadian groups. Pairwise FST and selection scans revealed signals of differentiation and selection at discrete genomic regions, including adjacent peaks on chromosome 10 across multiple pairwise comparisons (i.e. FST 0.5-0.75). Redundancy analysis suggested association of environmental variables related to benthic temperature and oxygen range with genomic structure. Results suggest regional scale diversity in this temperate reef fish and can directly inform the collection and translocation of cunner for aquaculture applications and the conservation of wild populations throughout the Northwest Atlantic.

Effect of build angle, resin layer thickness and viscosity on the surface properties and microbial adhesion of denture bases manufactured using digital light processing

ObjectivesTo investigate differences in the surface properties and microbial adhesion of denture base resins for digital light processing (DLP) with varying resin layer thicknesses (LT), build angles (BA), and resin viscosities. MethodsTwo denture base resins for DLP with different viscosities (high and low) were used to prepare disk specimens applying two manufacturing parameters: 1) LT (50 or 100 μm) and 2) BA (0-, 45-, and 90-degree). Surface roughness and contact angle values were measured on the test surfaces (n=10 per group). Streptococcus oralis and Candida albicans absorbance was measured to assess microorganism attachment (n=6 per group). A three-way analysis of variance (ANOVA) was conducted, considering the main effects and their interactions (viscosity, LT, and BA). Post-hoc multiple pairwise comparisons were performed. All data were analyzed at a level of significance (P) of 0.05. ResultsLT and BA significantly affected the surface roughness and contact angle of the specimens, depending on resin viscosity (P<.001). Absorbance measurement showed no significant interaction between the three factors (P>.05). However, significant interactions were observed between viscosity and BA (P<.05) and between LT and BA (P<.05). ConclusionsRegardless of the viscosity and LT, discs with a 0-degree BA showed the least roughness. High-viscosity specimens fabricated with a 0-degree BA had the lowest contact angle. Regardless of the LT and viscosity, discs with a 0-degree BA showed the lowest S. oralis attachment. Attachment of C. albicans was the least on the disk with 50 μm LT, irrespective of the viscosity. Clinical significanceClinicians should consider the effects of LT and BA on surface roughness, contact angle, and microbial adhesion of DLP-generated dentures, which can differ depending on resin viscosity. A 50 μm LT and 0-degree BA can be used with a high-viscosity resin to fabricate denture bases with less microbial adhesion.

Cyclic Fatigue Resistance of Different Glide Path Files in Simulated Double Curved Canal in Continuous Rotary Motion: An In Vitro Study.

This in vitro study aimed to compare and evaluate the resistance to cyclic fatigue of a newly developed glide path file in a simulated double curvature canal in a cyclic fatigue-testing machine. In this in vitro study, a static cyclic fatigue-testing machine with a simulated double curve was created and the samples were divided into the following three groups: Group I-HyFlex EDM; group II-TruNatomy file; and group III-Aurum G files and each instrument is continued to rotate in the canal and a number of cycles to failure (NCF) was calculated and Fractographic analysis was done using scanning electron microscope (SEM), and the results were statistically analyzed. Statistical analysis was done using parametric methods one-way analysis of variance (ANOVA) shows statistical significance between groups and then Tukey's HSD post hoc tests were used for multiple pairwise comparisons. TruNatomy glide path files had the highest cyclic fatigue resistance when compared to HyFlex EDM and Aurum G files. The selection of file systems in cleaning and shaping protocols is an enigma to endodontics. From the results of this study, it can be concluded that TruNatomy files had higher cyclic fatigue resistance than other glide path files are canals with double curvature, hence it is suitable for usage in root canals with extreme curvature. The selection of file systems in cleaning and shaping protocols is an enigma to endodontics. This in vitro study explored the selection protocols for the execution of root canal preparation. Heat treatment of nickel-titanium (NiTi) endodontic files had improved the cyclic fatigue resistance significantly enhancing the clinical life of file systems.

Optimal acupuncture protocol improving symptoms of typical dry eye syndrome: meta-analysis and systematic review

Previous meta-analyses have shown a superiority of acupuncture over artificial tear for treating typical dry eye syndrome (DES). However, given that the acupuncture protocols were quite diverse in the randomized controlled trials (RCTs) included in the meta-analyses, it is necessary to establish the acupuncture guidelines. Thus, the optimal acupuncture protocol involved in improvements of tear-film breakup time (BUT) or Schirmer tear test (STT) was examined by meta-analyses for RCTs in patients with typical DES. Eight databases until Jun 2018 were searched for 21 RCTs (n = 1542 eyes) comparing effectiveness of acupuncture versus artificial tear control. Indirect comparison of Bucher analysis was used to find specific acupoints (SAPs) improving BUT or STT by comparing the outcomes between subgroups of the RCTs including and excluding certain SAPs. Meta-analysis was examined for the outcomes in subgroups of the RCTs based on the number of SAPs, and network meta-analysis was for multiple pairwise comparisons across the protocols using the SAPs to yield relative effects. The Bucher analyses identified nine SAPs with positive effects on BUT or STT, and the positive relations of two SAPs involved in improvements of both BUT and STT suggested potential combinations of three (‘KI3–LI4–SP6’ or ‘KI3–GB14–ST2’) or four SAPs (‘KI3–BL1–EX-HN7–SP6’). Subgroup meta-analyses showed the SAP-depending improvements of BUT or STT in the subgroups including more than three SAPs, compared with the artificial tear control. Meta-regression and network meta-analyses revealed significant correlations between the number of SAPs and the improvements of BUT and STT, and demonstrated that acupuncture using four SAPs for 21–30 days, particularly at two–three times per week, can be optimal for improving the symptoms of typical DES. These results provide useful information for guiding acupuncture in clinical trials for DES.

Influence of Different Mouth Rinsing Agents on Friction During Sliding Mechanics Between Orthodontic Metal Brackets and Stainless Steel Archwire: A Comparative In Vitro Study.

Aim and objectives The aim of this in-vitro study is to evaluate and compare the effect of various mouth rinsing agents on frictional resistance through sliding mechanics among orthodontic metal brackets and stainless steel (SS) archwire. Materials and methods Each group comprised 15 samples of maxillary first premolar pre-adjusted edgewise SS movable, un-bonded brackets (Koden Inc., United States) which were welded with a power arm, where 100 gof the load was suspended. Brackets were ligated with elastic modules (Koden Inc., United States) onto the perspex sheet along with 0.019" x 0.025" SS archwire (Classic Orthodontics, United States) and were suspended from the upper component of the Instron machine. The coefficient of friction was tested in dry conditions (control), artificial saliva (AS) (Wet Mouth, ICPA Health Product Ltd., India), 0.2% chlorhexidine gluconate (CHG) mouthwash (Hexidine, ICPA Health Product Ltd., India), 0.05% sodium fluoride (NaF) mouthwash (ACT Anti-Cavity Fluoride Mouthwash, Sanofi Company, United States), charcoal (CC) mouthwash (Hello Activated Charcoal Extra Freshening Mouthwash, Hello Products LLC, United States) and ozone-infused oil-pulling solution with coconut oil (O3) (O3Essentials, Health Ranger Store, United States). In order to calculate the coefficient of friction, 50 L was addedto the test sample while moving at a 5 mm/min crosshead speed. The groups were compared using the one-way analysis of variance (ANOVA), and Tukey's post hoc analysis was performed for multiple pairwise comparisons. Results The coefficient of friction with the highest mean values was observed with the control group (2.01), followed by AS (1.79), and the least with O3(1.15). Statistically significant differences were observed with almost all groups of mouth rinsing agents, but NaF is significant with CHG and CC. However, CHG did not have any significant difference from CC. Conclusions Lower coefficient of frictional values were observed with the ozone-infused oil-pulling solution with coconut oil during sliding mechanics between metal brackets and stainless steel archwire. Almost all the mouth rinsing agents showed a significantly different coefficient of friction value.

The antimicrobial effects of Cold Atmospheric Plasma jet on microorganisms causing dental caries (in vitro study)

Background: The common microorganism in caries process are Streptococcus mutans and Lactobacilli. Candida albicans have correlation with Streptococcus mutans for enhanced dental caries. Cold Atmospheric Plasma (CAP) is called as non-thermal as result of electrons are more heated than heavy particles which are at room climate. CAP jets are ionized native gas outflow, produced underneath typical pressure through microwaves, high frequency or pulsed direct current employing noble gases. There are many application of CAP in dentistry: in periodontology, implantology, prosthodontic, operative dentistry and in cariology. This study aimed to measure the sensitivity of the S. mutans and C. albicans to CAP jet. Material and methods: In this experiment, newly developed Cold atmospheric plasma jet (Iraqi made) using argon gas at a Gas flow rate 10 l/min, 175volt and Frequency 2.45 GHz At room temperature such that the nozzle tip had a maximum distance of 2mm from the agar plate. Cold atmospheric plasma effect was tested at different times on the viable numbers of Streptococci mutans and Candida albicans. Result: Through the irradiation of CAP jet on agar plates the antimicrobial efficacy for S. mutans and C. albicans was measured at different time the 3, 6, 9 minutes. Multiple pairwise comparisons using Tukey HSD showed there is significant reduction of colony&#x0D; &#x0D; forming unit (CFU) for Streptococci mutans by plasma at all time compared to control. multiple pairwise comparisons using Tukey HSD showed there is highly significance differences for C. albicans was observed for all times in comparison to control (p&lt;0.01). The data of the current study was analyzed using statistical package for social science (SPSS version 22). Thus, it can be concluded that Cold Atmospheric plasma (argon gas) jet have anti-microbial efficacy against Streptococci mutans and Candida albicans. but it effects on Candida albicans more than on Streptococci mutans.

Innate Immune Cytokine Levels in Eyes With Late Endothelial Keratoplasty Failure.

The aim of this study was to compare aqueous humor cytokine levels in eyes with an initial endothelial keratoplasty (EK) that cleared and later decompensated versus control eyes. In this prospective case-control study, aqueous humor samples were collected under sterile conditions at the start of planned cataract or EK surgery in normal controls (n = 10), Fuchs dystrophy controls with no previous surgery (n = 10) or previous cataract surgery only (n = 10), eyes with Descemet membrane EK (DMEK) endothelial decompensation (n = 5), and eyes with Descemet stripping EK (DSEK) endothelial decompensation (n = 9). Cytokine levels were quantified with the LUNARIS Human 11-Plex Cytokine Kit and compared using the Kruskal-Wallis nonparametric test and post hoc Wilcoxon pairwise 2-sided multiple comparison test. Levels of granulocyte-macrophage colony-stimulating factor, interferon gamma, interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-10, IL-12p70, and tumor necrosis factorα did not differ significantly between groups. However, IL-6 was significantly increased in DSEK regraft eyes versus controls without previous ocular surgery. IL-8 was significantly increased in eyes with previous cataract or EK surgery versus eyes without previous surgery, and IL-8 was significantly increased in DSEK regraft eyes versus eyes with previous cataract surgery. The levels of innate immune cytokines IL-6 and IL-8 were elevated in the aqueous humor of eyes with failed DSEK, but not with failed DMEK. The differences between DSEK and DMEK may be related to the lower inherent immunogenicity of DMEK grafts and/or the more advanced stage of some of the DSEK graft failures at the time of diagnosis and treatment.

The effect of carbodiimide on push-out bond strength of fiber posts and endogenous enzymatic activity

BackgroundTo investigate the effect of 0.3 M 1-ethyl-3(3-dimethylaminopropyl) carbodiimide (EDC) aqueous solution pretreatment on push-out bond strength (PBS) and matrix-metalloproteinases (MMPs) activity within radicular dentin when different post cementation strategies were employed.MethodsOne hundred and twenty monoradicular human teeth were endodontically treated and randomly divided into six groups, depending on the cementation strategy and root dentin pretreatment (n = 20): EAR: cementation with an etch-and-rinse adhesive (LuxaBond Total Etch, DMG) and resin cement (LuxaCore Z Dual, DMG); EAR/EDC: 1 min EDC pretreatment after etching + EAR; SE: cementation with a self-etch primer (Multilink Primer, Ivoclar Vivadent) and corresponding cement (Multilink Automix, Ivoclar Vivadent); SE/EDC: self-etch primer + EDC pretreatment + SE; SA: cementation with a universal self-adhesive cement (RelyX Universal, 3 M); SA/EDC: EDC pretreatment + SA. Slices were submitted to PBS test and interfacial nanoleakage evaluation 24 h after cementation or after thermocycling (40.000 cycles, 5–55 °C). To investigate the effect of EDC on MMPs activity, 4 additional first maxillary premolars per group were processed for in situ zymography analysis. Multivariate ANOVA and post hoc Tukey tests were used to analyze PBS values. The data from in situ zymography were analyzed with Kruskal-Wallis test and Dunn’s pairwise multiple comparison procedures (α = 0.05).ResultsThe variables “EDC pretreatment”, “root region” and “thermocycling” significantly influenced PBS (p < 0.05), while the variable “cementation strategy” had no influence (p > 0.05). Thermocycling significantly reduced PBS in SE and SA groups (p < 0.05). EDC was effective in preserving PBS after artificial aging. EDC pretreatment significantly reduced enzymatic activity at baseline in EAR and SE groups, and in SA group after thermocycling (p < 0.05).ConclusionsThe use of EDC prevents the reduction of bond-strength values after artificial aging and silences endogenous enzymatic activity within radicular dentin when different cementation strategies were employed.

Establishing a Dexamethasone Treatment Regimen To Alleviate Sulfur Mustard-Induced Corneal Injuries in a Rabbit Model.

Sulfur mustard (SM) is an ominous chemical warfare agent. Eyes are extremely susceptible to SM toxicity; injuries include inflammation, fibrosis, neovascularization (NV), and vision impairment/blindness, depending on the exposure dosage. Effective countermeasures against ocular SM toxicity remain elusive and are warranted during conflicts/terrorist activities and accidental exposures. We previously determined that dexamethasone (DEX) effectively counters corneal nitrogen mustard toxicity and that the 2-hour postexposure therapeutic window is most beneficial. Here, the efficacy of two DEX dosing frequencies [i.e., every 8 or 12 hours (initiated, as previously established, 2 hours after exposure)] until 28 days after SM exposure was assessed. Furthermore, sustained effects of DEX treatments were observed up to day 56 after SM exposure. Corneal clinical assessments (thickness, opacity, ulceration, and NV) were performed at the day 14, 28, 42, and 56 post-SM exposure time points. Histopathological assessments of corneal injuries (corneal thickness, epithelial degradation, epithelial-stromal separation, inflammatory cell, and blood vessel counts) using H&E staining and molecular assessments (COX-2, MMP-9, VEGF, and SPARC expressions) were performed at days 28, 42, and 56 after SM exposure. Statistical significance was assessed using two-way ANOVA, with Holm-Sidak post hoc pairwise multiple comparisons; significance was established if P < 0.05 (data represented as the mean ± S.E.M.). DEX administration every 8 hours was more potent than every 12 hours in reversing ocular SM injury, with the most pronounced effects observed at days 28 and 42 after SM exposure. These comprehensive results are novel and provide a comprehensive DEX treatment regimen (therapeutic-window and dosing-frequency) for counteracting SM-induced corneal injuries. SIGNIFICANCE STATEMENT: The study aims to establish a dexamethasone (DEX) treatment regimen by comparing the efficacy of DEX administration at 12 versus 8 hours initiated 2 hours after exposure. DEX administration every 8 hours was more effective in reversing sulfur mustard (SM)-induced corneal injuries. SM injury reversal during DEX administration (initial 28 days after exposure) and sustained [further 28 days after cessation of DEX administration (i.e., up to 56 days after exposure)] effects were assessed using clinical, pathophysiological, and molecular biomarkers.

Effect of different interfacial surface treatments on the shear bond strength of veneering ceramic and zirconia core

BackgroundSeveral interfacial surface treatments of zirconia surfaces have been proposed to improve adhesion to ceramic veneering. However, information regarding the durability and effect of such treatments on the bond strength following such treatments is lacking.Aim of the studyThis study aimed to evaluate the shear bond strength between veneering ceramic and zirconia core after different interfacial surface treatments.Materials and methodsFifty-two discs (8 mm in diameter and 3 mm in height) were fabricated from zirconia blanks using a microtome cutting machine. Zirconia discs were divided into four groups (n = 13). Group I was subjected to air-borne abrasion using (Al2O3), group II was coated by bioglass, group III was coated with ZirLiner, and group IV was subjected to wash firing (sprinkle technique). A cylinder (4 mm in diameter and 3 mm in height) of veneering ceramic was fired on top of the zirconia core. Shear bond strength (SBS) between zirconia core and veneering ceramic was evaluated by using a universal testing machine. The data was collected and statistically analysed using One-Way ANOVA followed by multiple pairwise comparisons using Bonferroni adjusted significance level. The failure modes were assessed using a stereomicroscope for each group.ResultsThe highest mean bond strength was recorded in group III (17.98 ± 2.51 MPa), followed by group II (15.10 ± 4.53 MPa), then group I 14.65 ± 2.97 MPa. The lowest mean bond strength was recorded in group IV (13.28 ± 3.55 MPa).ConclusionsSurface treatments had an effect on the zirconia-veneer shear bond strength. Liner coating revealed the highest shear bond strength values, significantly higher in comparison to wash firing (sprinkle technique) .

Impact of a High-Power Light-Emitting Diode Unit With Reduced Curing Times on the Shear Bond Strength of Orthodontic Brackets and Their Adhesive Remnant Index Scores.

This study aims to evaluate the curing time minimally required for bonding stainless-steel (SS) brackets using a high-power light-emitting diode (LED) light curing unit (LCU) and examine the debonded enamel surface for adhesive remnant. Based on the LED LCU and curing time employed, 80 human maxillary first premolar teeth were equally segregated into four groups. Three groups were cured using a high-power LED unit (Guilin Woodpecker Medical Instrument Co., Ltd., Guilin, Guangxi, China) for one, two, and three seconds. The fourth group served as a control and was bonded with another intensive LED unit (Elipar™ S10 LED Curing Light; 3M, Saint Paul, Minnesota, United States) for 20 seconds. Transbond™ XT Light Cure Adhesive (3M, United States) adhesive was used for bonding the SS brackets. All the samples were exposed to shear bond strength (SBS) testing after a 24-hour immersion period in distilled water at 37°C. A stereomicroscope was used to examine and score the adhesive remnant on the debonded surface using a modified adhesive remnant index (ARI). Kruskal-Wallis-ANOVA and post-hoc Mann-Whitney U tests for multiple pairwise comparisons were performed to analyze the data. Time and intensity significantly affected the SBS (P<0.001). A higher SBS value (16.04 megapascals (MPa)) was obtained in the six-second group when compared to the three-second (11.58 MPa), one-second (10.69 MPa), and 20-second control (13 MPa) groups. The ARI was significantly affected by the curing method. Higher SBSs were recorded for the six-second group using the high-power LED. A greater ARI score is associated with a reduced curing duration and vice versa.

Disparate impact of healthcare access restrictions due to COVID-19 pandemic on breast cancer diagnosis and treatment.

e13518 Background: The COVID-19 pandemic altered healthcare access avenues for patients. In May 2020, 79% of cancer patients in the US in active treatment experienced some delay in their healthcare due to COVID-19 related restrictions. Hispanic patients are known to be disproportionately affected by their social determinants of health, and therefore are at higher risk of being affected by the pandemic. Our institution, designated as a “Hispanic Serving Institute (HSI)”, is ideally suited to study the impact of the pandemic on this population. Methods: In this retrospective study, the institutional breast cancer database was queried for patients managed between January 1, 2018 and April 18, 2022. Socio-demographic variables, screening, and treatment initiation dates were analyzed to determine the impact of COVID-19 related restrictions. Patients were stratified into groups based on date of diagnosis: Group 1 (pre-pandemic), Group 2 (pandemic), and Group 3 (post pandemic). Statistical analyses were conducted using R statistical software (R version 4.1.3). ANOVA or Kruskal Wallis tests with multiple pairwise comparisons using independent samples t-test or Wilcoxon rank sum test and χ2 tests with multiple pairwise comparisons using Fisher’s exact test were used to compare the groups. Interaction models were created to evaluate the association between 1) Ethnicity and 2) Distance from the treatment center on the time lapses between 1) mammogram and biopsy and 2) biopsy and first treatment separately. Results: Of the 488 patients during study period, 163 (33%) patients were Hispanic. Median (IQR) number of days between biopsy and first treatment was similar across all groups [Group 1=39.5 (102.5) days; Group 2= 50 (121) days; Group 3=57 (54) days - p=0.338]. Patients who lived &gt; 50 miles away from the treatment facility experienced longer time lapses between biopsy date and first treatment compared to those living ≤ 50 miles away (β= 40.60, SE (standard error) =20.87, p = 0.052). Compared to Non-Hispanics, Hispanics in Group 2 experienced a shorter time lapse between mammogram and biopsy (β= -17.34, SE=5.46, p = 0.002). However, these patients experienced a longer time lapse between biopsy and initiation of treatment (β= 43.57, SE=18.25, p = 0.017). There was a significantly higher proportion of non-insured patients in the Hispanic group compared to the non-Hispanic group [Hispanic group=12 (7.4%) patients; Non-Hispanic group=8 (2.5%) patients - p=0.020]. Conclusions: Pandemic related delays in breast cancer treatment were observed mainly in Hispanics and patients living more than 50 miles from the treatment center.

Incidence and severity of nonionic low-osmolar iodinated contrast medium-related adverse drug reactions in the Republic of Korea: Comparison by generic.

We aimed to report the incidence and severity of nonionic low-osmolar iodine contrast medium (ICM)-related adverse drug reactions (ADRs) in the Republic of Korea, by analyzing data from our single tertiary institution and published Korean reports, and to determine whether there is a difference in the incidence of ICM-related ADR by ICM generics. A total of 1,161,419 consecutive contrast-enhanced computed tomography (CT) examinations between January 2016 and December 2021 at Asan Medical Center were included. A systematic search of the literature investigating the incidence of ICM-related ADR in the Republic of Korea published up to December 31, 2021 was performed. We pooled these outcomes with those of our study using a binomial-normal model, and the pooled incidences of ADRs were compared among ICM generics using chi-square tests. Seven studies with a total of 2,570,986 contrast-enhanced CT examinations from 12 institutions were included. The pooled incidences of overall, mild, moderate, and severe ICM-related ADRs in the Republic of Korea were 0.82% (95% CI: 0.61%-1.10%), 0.72% (95% CI: 0.50%-1.04%), 0.11% (95% CI: 0.08%-0.15%), and 0.013% (95% CI: 0.010%-0.018%), respectively. In multiple pairwise comparisons, there were no significant differences in the overall incidence of ADRs between ICM generics, except iomeprol versus iobitridol and iomeprol versus iohexol. For moderate and severe ADRs, there were no significant differences in ADR incidence between ICM generics. The incidence of moderate and severe ICM-related ADRs did not differ among ICM generics. Our results suggest that no restriction is required for selection among nonionic low-osmolar ICMs.