Tag: pubmed

Am J Dent. 2026 Aug;39(4):201-205.

ABSTRACT

PURPOSE: To investigate whether the amount of dentifrice (dose) used per brushing affects the abrasion of the hard tooth tissues.

METHODS: Enamel and dentin specimens were subjected to simulated brushing with two commercial dentifrices (Prodent, Smyle dentifrice in tablet form) and positive as well as negative controls at varying amounts of dentifrices (standard dose, half, and double dose). Brushing without dentifrice (with water) functioned as a negative control. Tooth wear was quantified using profilometry, and statistical analysis was performed using one-way ANOVA and Tukey’s post hoc test (α= 0.05).

RESULTS: For enamel, dose variations had minimal impact. However, dentin wear increased significantly with higher doses, particularly for the positive control and Smyle at double dose (P< 0.05). Dilution reduced abrasivity inconsistently across brands.

CLINICAL SIGNIFICANCE: The amount of dentifrice used for brushing has a significant, dose-dependent effect on dentin abrasion, whereas enamel is relatively unaffected, and brushing without dentifrice does not cause wear. While dentifrice in tablet form provides a manufacturer‑defined standard amount per brushing, this is not the case for dentifrice in paste form. Because the amount of dentifrice used influences dentin wear, it is advisable that manufacturers clearly define the recommended quantity of dentifrice for a single brushing.

PMID:42571899

Am J Dent. 2026 Aug;39(4):193-200.

ABSTRACT

PURPOSE: To evaluate in the laboratory the effect of an in-office whitening agent on color change, translucency, and surface roughness of leucite-reinforced CAD-CAM material with different surface finishes exposed to different beverages [cola, tea, fruit juice, coffee, distilled water (Control)].

METHODS: All the IPS Empress CAD-CAM ceramic block specimens were treated with a glaze layer (n=75) and then randomly divided into three groups. The samples (n=25) in Group 1 (Control) were not treated (glaze layer remained). The glaze layer of the other samples (n=50) was abraded by the same researcher. While the samples in Group 2 were treated with Optrafine (Optrafine after glazing) (n=25), those in Group 3 were subjected to surface treatment with Eve polishing kits (Eve kit after glazing) (n=25). The samples were then immersed in five different beverages (cola, coffee, tea, fruit juice and distilled water) (n=5) and clinic-type bleaching was applied. Color measurements were recorded by spectrophotometer and surface roughness (Ra) values were recorded by profilometer. Color change (ΔE₀₀) values were calculated using the CIE2000 formula. The data were statistically analyzed using Shapiro-Wilk test, ANOVA and Bonferroni test (P< 0.05).

RESULTS: Regardless of the surface finishing process and beverage, the mean values of color change (ΔE₀₀) did not differ according to time (P= 0.148). As a result of the ANOVA, surface finishing process, beverage, and time interaction were found to be very significant (P< 0.001). Regardless of the surface finishing process and beverage, it was determined that the mean roughness values differed according to time (P= 0.019).

CLINICAL SIGNIFICANCE: Although bleaching glass ceramic restorations with bleaching agents containing 40% hydrogen peroxide was effective to remove stains, maintaining the glaze surface finish is critical for color stability and surface integrity of CAD-CAM ceramics.

PMID:42571898

Tumori. 2026 Aug 9:3008916261473076. doi: 10.1177/03008916261473076. Online ahead of print.

ABSTRACT

The increasing complexity of precision medicine has highlighted the limitations of traditional randomized clinical trials (RCTs) when applied to highly stratified populations and biologically heterogeneous diseases. In this context, master protocols represent an evolution towards integrated experimental infrastructures, capable of simultaneously evaluating multiple interventions or molecular subgroups within a single methodological framework.These designs redefine the role of randomization in complex settings. Conventional RCTs remain indispensable as confirmatory studies, thanks to their methodological rigor and the robustness of the evidence they generate.Future developments will depend on the capacity to ensure statistical rigor, transparent governance, data protection and equitable access to experimental infrastructures and advanced molecular screening. In this evolving landscape, master protocols emerge not as a methodological trend, but as one of the most convincing tools for making evidence generation faster, more flexible, and more sustainable without giving up the scientific standards required by contemporary clinical research.

PMID:42571682 | DOI:10.1177/03008916261473076

Bull Math Biol. 2026 Aug 9;88(9):151. doi: 10.1007/s11538-026-01719-y.

ABSTRACT

Vaccine-related communication can be harnessed to curb infection; yet, in practice, it often undermines vaccine uptake and sustains transmission even when effective vaccines are available. Our goal is to understand how vaccine information dynamics may shape infection spread within a coupled information-infection modeling framework. We present a coupled information-infection modeling framework that links a standard SVIRS infection-spread model with an integrate-and-fire-inspired information-dissemination model. Vaccine-positive and vaccine-critical active groups disseminate competing information that shapes non-active/hesitant individuals’ vaccine attitudes through direct peer influence, threshold-based acceptance, and persistence of engagement, while infection prevalence can feed back by amplifying caution. The evolving vaccine attitudes modulate vaccination uptake, and the model tracks the joint evolution of information dynamics and epidemic trajectories. Our analysis shows that, under the assumed coupling, information dynamics can shift the system among qualitatively distinct infection outcomes. In particular, reducing resistance to vaccine-positive information and sustaining vaccine-positive engagement can move the system toward lower-endemic regimes more reliably than changes focused only on weakening vaccine-critical engagement, for the parameter ranges considered here. These findings highlight the potential importance of information dynamics in epidemic modeling and suggest that sustained vaccine-positive engagement can be an important qualitative mechanism for reducing long-term infection burden.

PMID:42571670 | DOI:10.1007/s11538-026-01719-y

Mycorrhiza. 2026 Aug 9;36(4):57. doi: 10.1007/s00572-026-01301-3.

ABSTRACT

Tropical Africa encompasses several biodiversity hotspots, yet knowledge of ectomycorrhizal (EcM) fungi, key organisms for forest ecosystem functioning, remains fragmented. This study provides the first comprehensive synthesis of EcM fungi across the region, aiming to (i) establish a species checklist as a basis for estimating gamma diversity, (ii) analyze spatial turnover across countries, and (iii) assess the functional effects of EcM fungi on tree seedling growth. We conducted a systematic literature search following PRISMA guidelines, retaining 158 publications published between 1927 and 2025. Species occurrence records were extracted from publications and complemented with data from GlobalFungi and GBIF databases. Statistical analyses in R were used to estimate species richness (Chao2, Jackknife 1 and Jackknife 2), analyze spatial turnover (Jaccard dissimilarity, Mantel correlogram, Generalized Dissimilarity Modelling), and assess the overall effect on tree seedling growth (cross-classified random-effects meta-analysis). We recorded 711 EcM fungal species from 59 genera and 20 families. Russula (169 species), Amanita (81), and Lactifluus (71) were the most represented. Estimated richness reached 1,226 species, indicating substantial undocumented diversity. Community composition showed extremely high heterogeneity among countries (95% dissimilarity), and increased turnover over broader geographic distances (r = -0.13, p < 0.05), suggesting dispersal limitation. Meta-analysis revealed that EcM fungi increased tree seedling growth by an average of 6% per month (p < 0.05), with Scleroderma verrucosum showing particularly strong positive effects. These findings indicate that EcM fungi are unevenly distributed across tropical Africa. They refine our understanding of diversity patterns and highlight the need for targeted sampling and integrating native EcM fungi into forest restoration.

PMID:42571669 | DOI:10.1007/s00572-026-01301-3

Bull Math Biol. 2026 Aug 9;88(9):152. doi: 10.1007/s11538-026-01724-1.

ABSTRACT

Ecological interactions shape the dynamics of natural populations in the wild. Density-dependent processes are widespread and may change the respective effects of populations on one another, for instance by shifting interactions from mutualistic to parasitic relationships. Here, we develop a general deterministic model of two interacting populations, assuming density-dependent costs and benefits for the interacting individuals within and between species. This framework aims at generalizing pre-existing population dynamics models involving competition, predation, mutualism and parasitism, by allowing ecological interactions to transition when the respective densities of interacting species change. Through ordinary differential equations and phase portrait analysis, we derive general principles governing these systems, identifying constraints on the organization of equilibria and sufficient conditions for the emergence of certain dynamic behaviors. In particular, we show that equilibrium indices alternate along isoclines under broad geometric assumptions, and that limit cycles can arise when interactions include mutualistic and parasitic phases, while they cannot be generated locally in strictly mutualistic regions where the relevant interaction signs remain fixed. This framework provides a general approach for characterizing the population dynamics of interacting species and highlights the effect of the density dependent transitions in ecological interactions.

PMID:42571666 | DOI:10.1007/s11538-026-01724-1

Chem Biodivers. 2026 Aug;23(8):e71584. doi: 10.1002/cbdv.71584.

ABSTRACT

This study evaluated how geographical origin (El Alamein vs. Red Sea regions in Egypt) and extraction methods saffect the chemical profile and antimicrobial efficacy of Cotula cinerea essential oils. Comparing conventional hydro-distillation (HD) to microwave-assisted extraction (MAE), researchers found that MAE delivered higher oil yields (0.35%-0.37%) than HD (0.31%-0.34%) in significantly less time. Gas chromatography-mass spectrometry (GC/MS) identified 19 volatile compounds-predominantly oxygenated monoterpenes like pinocarvone, α-thujone, and camphene-with statistical analyses confirming that both location and extraction technique distinctly altered this chemical composition. Furthermore, MAE-extracted oils demonstrated superior antimicrobial activity, particularly those from El Alamein, which reached a notable 25 mm inhibition zone against Aspergillus niger. Ultimately, the results indicate that MAE is a highly efficient and reproducible method for harvesting bioactive C. cinerea oils for potential pharmaceutical and nutraceutical applications.

PMID:42571628 | DOI:10.1002/cbdv.71584

Cureus. 2026 Jul 8;18(7):e112307. doi: 10.7759/cureus.112307. eCollection 2026 Jul.

ABSTRACT

INTRODUCTION: Short dental implants have been proposed as a minimally invasive alternative to standard implants for rehabilitation of posterior edentulous regions with limited bone availability. However, concerns remain regarding their long-term survival and risk of failure compared to standard-length implants. This study aimed to compare the survival and failure rates of short (<10 mm) and standard (≥10 mm) dental implants placed in the posterior maxilla and mandible.

MATERIALS AND METHODS: This retrospective cohort study included 207 patients who received 363 dental implants in the posterior jaw. The implants were categorized as short implants (<10 mm; n = 141) and standard implants (≥10 mm; n = 222). Demographic characteristics, implant-related variables, and clinical outcomes were retrieved from the patient records. Implant failure, survival rates, and the influence of jaw location on implant outcomes were assessed. Statistical analyses included chi-square test or Fisher’s exact test, independent-samples t-tests, and odds ratio calculations. Statistical significance was set at p < 0.05.

RESULTS: The mean age of the study population was 52.1 ± 10.5 years, with 142 (68.6%) males and 65 (31.4%) females. Overall, implant failure was significantly higher among short implants than among standard implants (p < 0.001). Standard implants demonstrated significantly lower odds of failure than short implants (OR = 0.29; 95% CI: 0.15-0.57). In the maxilla, the failure rates were 18 (28.6%) for short implants and 8 (8.5%) for standard implants (p = 0.002), whereas in the mandible, the corresponding rates were 10 (12.8%) and 7 (5.5%), respectively (p = 0.110). The cumulative survival rates were lower for short implants as compared to standard implants.

CONCLUSION: Standard dental implants demonstrated significantly higher survival rates and lower failure rates than short implants in posterior jaw rehabilitation. Although short implants remain a useful treatment option in anatomically restricted sites, careful case selection is necessary, particularly in the posterior maxilla, where the risk of failure appears to be greater.

PMID:42571603 | PMC:PMC13452643 | DOI:10.7759/cureus.112307

PeerJ. 2026 Aug 5;14:e21593. doi: 10.7717/peerj.21593. eCollection 2026.

ABSTRACT

BACKGROUND: Traumatic brain injury (TBI) frequently results in persistent emotional and cognitive dysfunction, yet the neural mechanisms underlying these deficits remain incompletely understood. This study examined the impact of non-severe TBI (nTBI) on emotional processing, with a focus on brain activation, functional connectivity, effective connectivity, and their relationship to cognitive performance.

METHODS: Twenty right-handed male nTBI participants (mean age: 30.70 ± 11.78 years) and 20 age-matched healthy male controls (mean age: 27.85 ± 7.73 years) underwent functional magnetic resonance imaging (fMRI) while viewing emotional images from the International Affective Picture System (IAPS). Brain activation was analyzed using Statistical Parametric Mapping (SPM12). Functional connectivity was assessed with seed-based analysis (medial visual network, mVN) using the CONN toolbox. Effective connectivity was evaluated using dynamic causal modeling (DCM) and parametric empirical Bayes (PEB). Neuropsychological assessments covering memory, intelligence, and executive function were included to characterize general cognitive function within the cohort, with exploratory analyses examining relationships with connectivity measures.

RESULTS: Compared to controls, the nTBI group exhibited reduced activation in the calcarine cortex and lingual gyrus during emotional processing. Functional connectivity analysis showed decreased mVN connectivity with the frontal pole and dorsal anterior cingulate cortex (dACC), with increased mVN-ACC and mVN-supramarginal gyrus connectivity specifically during negative emotion processing. Effective connectivity analysis revealed altered directional influences within visual-limbic-cognitive control networks, including altered mVN-to-dACC and right amygdala-to-dACC connectivity patterns, as well as valence-specific modulation of self-inhibition. Exploratory analyses suggested potential correlations between connectivity alterations and cognitive performance, though these relationships varied across domains and should be interpreted cautiously.

CONCLUSIONS: Non-severe TBI disrupts emotional network function by altering both functional and effective connectivity, particularly in visual, limbic, and cognitive control regions. These alterations may contribute to emotional dysregulation following injury. Findings support the relevance of brain connectivity-based markers in understanding post-TBI emotional processing and highlight potential targets for intervention. Interpretations should be made cautiously, given the study limitations, including the use of static visual stimuli and a homogenous male sample.

PMID:42571587 | PMC:PMC13452427 | DOI:10.7717/peerj.21593

Cureus. 2026 Jul 9;18(7):e112345. doi: 10.7759/cureus.112345. eCollection 2026 Jul.

ABSTRACT

Background Epilepsy, chronic monotherapy of antiseizure medications (ASMs), as well as the secondary disturbance of the thyroid axis, which includes both subclinical and clinical hypo- and hyperthyroidism, are crucial endocrine challenges during children’s development. In this study, the levels of thyroid hormones in children with epilepsy who underwent chronic monotherapy were compared with those of healthy children with no history of seizures and no experience with anticonvulsants. Moreover, in this study, the goal was to identify the actual rates, dynamics, and dose-dependence of thyroid dysfunction in the aforementioned study population. Methodology A prospective, observational, case-control study was conducted involving 150 patients with epilepsy on ASM treatment (cases) and 150 healthy control subjects who were matched for age and sex from a pediatric outpatient/inpatient department. The history, classification of seizures, and ASMs were documented. Serum thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) were measured using the electro-chemiluminescent immunoassay test. Statistical analysis was performed using SPSS version 28 through one-way analysis of variance and paired Student’s t-test. Results Patients exhibited a significantly higher mean TSH level (3.82 ± 2.21 vs. 2.89 ± 1.12 mIU/L; p < 0.001) and a significantly lower mean fT4 level (1.28 ± 0.29 vs. 1.35 ± 0.31 ng/dL; p = 0.012), while fT3 characteristics did not change (p = 0.45). Analyses of subgroups revealed that atypical febrile seizures (4.56 ± 2.67 mIU/L) and generalized tonic-clonic seizures (4.12 ± 2.45 mIU/L) exhibited the most significant predisposition to extreme elevations in TSH levels (p = 0.004). Regarding treatment options, patients undergoing sodium valproate monotherapy presented the highest mean TSH levels (4.02 ± 2.11 mIU/L; p = 0.001), but levetiracetam appeared to be an effective thyroid-preserving choice and provided a more favorable fT4 profile (1.35 ± 0.33 ng/dL; p = 0.020). Regarding timing, the TSH peak occurred significantly between six and nine months of the drug administration period (4.35 ± 2.41 mIU/L; p = 0.024). In addition, a clear dose-dependent pattern was detected, with mean TSH levels rising progressively to a maximum of 5.20 ± 3.12 mIU/L within the highest 25-30 mg/kg dosing range (p = 0.008), representing a notable 31% endocrine elevation. Conclusions Children with epilepsy receiving maintenance therapies with sodium valproate or phenytoin have a considerable chance of suffering from subclinical hypothyroidism, which increases sharply between six and nine months of treatment at high doses. Thyroid function monitoring is strongly advised within the first year of treatment, along with dose adjustment and evaluation of thyroid-sparing drugs, such as levetiracetam.

PMID:42571574 | PMC:PMC13452441 | DOI:10.7759/cureus.112345