Category: Statistics

Eur J Dent. 2021 Aug 24. doi: 10.1055/s-0041-1729677. Online ahead of print.

ABSTRACT

OBJECTIVE: The objective of this study was to evaluate the hemostatic activity of the sap from Jatropha mollissima (Pohl) Baill. in rats.

MATERIALS AND METHODS: Twenty-four Wistar rats were randomized into four groups (n = 6): the JM25 and JM40 groups were treated with ethanolic extract from the sap of J. mollissima, in a concentration of 25 and 40 mg·mL¹, respectively; the MO group was treated with Monsel’s solution and the control group SC with a 0.9% sodium chloride solution.

STATISTICAL ANALYSIS: Data were submitted to the Kurskal-Wallis’ test, followed by Dunn’s post hoc (p < 0.05).

RESULTS: There was a significant reduction in the bleeding time of the group from the JM25 extract (p = 0.001) when compared with MO and SC. There were no statistically significant differences between groups JM25 and JM40 (p > 0.05). The JM25 group did not present rebleeding, a result significantly different from the MO group (p = 0.001). Monsel’s solution showed significant bleeding, six times greater than the control group SC.

CONCLUSION: The J. mollissima extract, in the concentration of 25 mg·mL¹, showed the highest hemostatic efficiency and was found to be a promising biomaterial for the elaboration of a hemostatic product.

PMID:34428842 | DOI:10.1055/s-0041-1729677

Eur J Dent. 2021 Aug 24. doi: 10.1055/s-0041-1731888. Online ahead of print.

ABSTRACT

OBJECTIVE: The focus of this study was to evaluate the biocompatibility of ionomer cements modified with ethanolic extracts of propolis (EEP) in different concentrations and time intervals.

MATERIALS AND METHODS: In total, one hundred and thirty-five male Wistar rats were randomized into nine groups: Control, Groups Meron, and Groups Ketac (conventional, and added with 10, 25, 50% EEP, respectively). Histological analyses of inflammatory infiltrate and collagen fibers, and immunohistochemistry of CD68+ for macrophages (MOs) and multinucleated giant cells (MGCs) were performed.

STATISTICAL ANALYSIS: Data were analyzed using the Kruskal-Wallis and Dunn (p < 0.05) tests.

RESULTS: Intense inflammatory infiltrate was demonstrated in the cements with 10% EEP at 7 days and 15 days (p < 0.05), only Group Ketac 10% EEP (p = 0.01) at 30 days. A smaller quantity of collagen fibers was observed in the cements with 10% EEP (p = 0.01) at 7 days, and Group Meron 10% EEP (p = 0.04) at 15 days. MOs and MGCs showed significant difference for the cements with 10% EEP (p = 0.01) at 7 and 15 days. At 30 days, MOs persisted in the Groups with 10% EEP.

CONCLUSIONS: The concentration of 10% EEP had the greatest influence on the inflammatory and tissue repair processes. The concentrations of 25 and 50% EEP demonstrated biocompatibility similar to that of cements that did not receive EEP.

PMID:34428843 | DOI:10.1055/s-0041-1731888

Eur J Dent. 2021 Aug 24. doi: 10.1055/s-0041-1727556. Online ahead of print.

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the microbiological and mechanical properties of glass ionomer cement (GIC) modified by chlorhexidine (CLX) for the purpose of cementing bands to the teeth of orthodontic patients.

MATERIALS AND METHODS: Ten patients, between the ages of 19 and 33 years, in the initial stage of orthodontic treatment, were randomly designated to two groups using the split-mouth design (n = 10). One group (GICEX) had bands cemented with GIC modified by CLX and a Control group (GIC), evaluated at time intervals before (T0), 3 months (T3), and 6 months (T6) after cementation. Total microbiological counts were performed, and color stability of tooth enamel, salivary pH, and the adhesive remnant index (ARI) were evaluated.

STATISTICAL ANALYSIS: The Friedman and Dunn’s tests, Mann-Whitney, one-way analysis of variance, and Tukey, and paired and non-paired t-tests (p< 0.05) were used.

RESULTS: In T3, there was evidence of significant reduction in the quantity of colony forming unit (CFU) in GICEX group in comparison with the Control (p = 0.041). In T6, the quantity of CFU was similar to the quantity in T3 and significantly different to control (p = 0.045); Control group demonstrated a similar quantity of CFU between the experimental time intervals (p = 0.066). Salivary pH demonstrated significant difference only between the time intervals T0 and T6 (p = 0.022). The tooth enamel color (p = 0.366) and ARI (p = 0.343) values demonstrated no significant changes.

CONCLUSION: The incorporation of CLX into GIC demonstrated effective antibacterial action, allowed a good bond of the cement to the enamel, a high rate of survival of the bands, did not change the color of the tooth enamel, and maintained the salivary pH at physiological levels.

PMID:34428840 | DOI:10.1055/s-0041-1727556

Eur J Dent. 2021 Aug 24. doi: 10.1055/s-0041-1731852. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of this study is to test knowledge, attitudes, and behavior of the students from the Bjelovar University of Applied Sciences in relation to oral health, and to determine the respectable differences between students of nursing and technical study programs.

PARTICIPANTS AND METHODS: Students were randomly selected to represent a convenient sample. A total of 140 students from nursing and technical studies were interviewed by using the World health organization Oral Health Questionnaire, adapted to fit the study purposes.

STATISTICAL ANALYSIS: Descriptive statistics were used to determine frequency distribution and percentages for all variables. Pearson’s Chi-square test was used to compare the proportions. A p-value less than 0.05 was considered to be statistically significant.

RESULTS: The distribution of participants regarding gender was significantly different between the study programs (p = 0.000). Significant difference was also observed in their perceived socioeconomic status (p = 0.001). A significant difference was found between the study programs regarding the knowledge whether bad teeth could impair general health (p = 0.001), could tooth decay and periodontal disease may be prevented (p = 0.002), as well as the importance of regular dental check-ups for prevention of tooth decay (p = 0.028). There were significant differences regarding dietary habits and alcohol consumption in the past 30 days between the observed study programs (p = 0.000) while no significant differences were found regarding tobacco and tobacco product use (p = 0.170).

CONCLUSION: Results obtained and presented in this paper show better knowledge and more favorable habits and behaviors among the students from nursing study program compared with the technical ones. Still all students’ habits should be changed to improve oral health. To change attitudes and influence habits, effective oral health promotion programs are needed; not only in colleges, but also in primary and secondary schools.

PMID:34428841 | DOI:10.1055/s-0041-1731852

Eur J Dent. 2021 Aug 24. doi: 10.1055/s-0041-1729676. Online ahead of print.

ABSTRACT

OBJECTIVES: This study aimed to test the efficacy of two experimentally produced eggshell-based toothpastes on dentinal tubules occlusion.

MATERIALS AND METHODS: Two experimental eggshell toothpastes, based on natural ingredients, with or without titanium dioxide nanoparticles (TNPs) were produced and coded “TNPs eggshell toothpaste [TNPsESTP]” or “eggshell toothpaste [ESTP],” respectively. Mid-coronal dentin discs, from 28 human extracted molar teeth, etched with 37% phosphoric acid for 60 seconds to simulate the hypersensitive dentin, were randomly divided into four groups-G1: no treatment (negative control), G2: ESTP treated, G3: TNPsESTP treated, and G4: Biorepair treated (positive control). All treated discs were brushed for 2 weeks and 1 month using a toothbrush simulator at 40 mm/s. Dentinal tubules occlusion was studied using a cross-polarization optical coherence tomography (CP-OCT) and scanning electron microscopy (SEM).

STATISTICAL ANALYSIS: Unpaired t-test was conducted using GraphPad software (San Diego, California, United States). Continuous variables were expressed as means ± standard deviation and p < 0.05 was considered statistically significant.

RESULTS: From CP-OCT, a marked increase in surface reflectivity of dentin was observed after brushing with tested toothpastes. ESTP and NPsESTP showed higher or comparable grayscale values than Biorepair indicating increase in surface density of dentin. From SEM, at 2 weeks, ESTP showed comparable number of completely occluded dentinal tubules to Biorepair. TNPsESTP showed significantly lower numbers of CODT than Biorepair. At 1 month, the number of CODT was difficult to count for all treated groups. Both ESTP and TNPsESTP showed significantly higher numbers of partially occluded dentinal tubules than Biorepair.

CONCLUSION: ESTP or TNPsESTP could offer a cost-effective substitute for the treatment of dentin hypersensitivity.

PMID:34428838 | DOI:10.1055/s-0041-1729676

J Cogn Neurosci. 2021 May 1;33(6):1197-1209. doi: 10.1162/jocn_a_01709.

ABSTRACT

Does early exposure to cognitive and linguistic stimulation impact brain structure? Or do genetic predispositions account for the co-occurrence of certain neuroanatomical phenotypes and a tendency to engage children in cognitively stimulating activities? Low socioeconomic status infants were randomized to either 5 years of cognitively and linguistically stimulating center-based care or a comparison condition. The intervention resulted in large and statistically significant changes in brain structure measured in midlife, particularly for male individuals. These findings are the first to extend the large literature on cognitive enrichment effects on animal brains to humans, and to demonstrate the effects of uniquely human features such as linguistic stimulation.

PMID:34428792 | DOI:10.1162/jocn_a_01709

J Cogn Neurosci. 2021 May 1;33(6):1056-1068. doi: 10.1162/jocn_a_01704.

ABSTRACT

Behavioral studies have shown that statistical properties of object groups are perceived accurately with brief exposure durations. This finding motivated the hypothesis that ensemble perception occurs rapidly in vision. However, the precise timing of ensemble perception remains unclear. Here, we used the superior temporal resolution of electroencephalography to directly compare the timing of ensemble processing to that of individual object processing. The P3b was chosen as a particular component of interest, as it is thought to measure the latency of stimulus evaluation. Participants performed a simple “oddball” task in which sets of 51 lines with varied orientations sequentially flashed briefly on the display. In these sequences, there was a 20% chance of an individual oddball, wherein one marked object tilted clockwise, and a 20% chance of an ensemble oddball, wherein the average orientation of the set tilted clockwise. In counterbalanced blocks, participants were instructed to respond to either individual or ensemble oddballs. ERP analysis was performed to test the timing of this processing. At parietal electrodes, P3b components were found for both individual and ensemble oddballs. Ensemble P3b components were found to occur significantly earlier than individual P3b components, as measured with both 50% area latency and 50% onset latency. Using multivariate pattern analysis, ensemble oddball trials were classifiable from standard trials significantly earlier in their timecourse than individual oddball trials. Altogether, these results provide compelling evidence that ensemble perception occurs rapidly and that ensemble properties can be available earlier than individual object properties.

PMID:34428790 | DOI:10.1162/jocn_a_01704

J Clin Psychiatry. 2021 Aug 24;82(5):20m13723. doi: 10.4088/JCP.20m13723.

ABSTRACT

Objective: Insomnia is prevalent and is associated with a range of negative sequelae. Cognitive behavioral treatment for insomnia (CBT-I) is the recommended intervention, but availability is limited. Telehealth provides increased access, but its efficacy is not certain. The objective of this study was to compare the efficacy of CBT-I delivered by telehealth to in-person treatment and to a waitlist control.

Methods: Individuals with DSM-5 insomnia disorder (n = 60) were randomized to telehealth CBT-I, in-person CBT-I, or 8-week waitlist control. CBT-I was delivered over 6-8 weekly sessions by video telehealth or in-person in an outpatient clinic. Follow-up assessments were at 2 weeks and 3 months posttreatment. The Insomnia Severity Index (ISI) was the primary outcome. Change in ISI score was compared between the CBT-I group in an intent-to-treat, noninferiority analysis using an a priori margin of -3.0 points. All analyses were conducted using mixed-effects models. Data collection occurred from November 2017-July 2020.

Results: The mean (SD) change in ISI score from baseline to 3-month follow-up was -7.8 (6.1) points for in-person CBT-I, -7.5 (6.9) points for telehealth, and -1.6 (2.1) for waitlist, and the difference between the CBT-I groups was not statistically significant (t₂₈ = -0.98, P = .33). The lower confidence limit of this between-group difference in the mean ISI changes was greater than the a priori margin of -3.0 points, indicating that telehealth treatment was not inferior to in-person treatment. There were significant improvements on most secondary outcome measures but no group differences.

Conclusions: Telehealth CBT-I may produce clinically significant improvements in insomnia severity that are noninferior to in-person treatment. CBT-I is also associated with significant gains across a range of domains of functioning. Telehealth is a promising option for increasing access to treatment without loss of clinical gains.

Trial Registration: ClinicalTrials.gov identifier: NCT03328585.

PMID:34428360 | DOI:10.4088/JCP.20m13723

J Basic Clin Physiol Pharmacol. 2021 Jun 22. doi: 10.1515/jbcpp-2020-0183. Online ahead of print.

ABSTRACT

OBJECTIVES: There is extensive data pointing to offspring outcomes related to maternal life incidents, but there is less research concerning the association between paternal life events and progeny brain development and behaviour. As male gametogenesis is a continuous process, the incidences happening in life can modify the epigenetic regulation, altering the offspring’s development and behaviour. The present study evaluates the effects of paternal stress during different life periods on their offspring’s learning ability, memory, morphological and biochemical changes in the prefrontal cortex and hippocampus in the rat model.

METHODS: Four weeks’ old male rats were subjected to five variable stressors at the rate of one per day. Stress received male rats were bred with naive female rats for 1 to 3 nights. The offspring’s learning and memory were assessed by the Morris water maze test and automated Y maze. Following behavioural studies, offspring were euthanized to examine global DNA methylation, neurotransmitter levels, namely acetylcholine, glutamate in the hippocampus and frontal cortex.

RESULTS: The offspring of stress-induced animals exhibited a delay in acquiring learning and defect in memory and altered global DNA methylation in the hippocampus (p=0.000124). There was significant reduction of acetylcholine and glutamate levels in hippocampus (p=0.000018, p=0.00001, respectively) and in prefrontal cortex (p=0.00001, p=0.00001, respectively). HPA axis of offspring was altered considerably (p=0.00001). The histomorphometry of the prefrontal cortex and different hippocampal regions revealed a statistically significant (p<0.05) reduction in neuronal numbers in the offspring of stressed animals compared to that of control. These impacts were markedly high in the offspring of fathers who received stress during both pubertal and adult periods.

CONCLUSIONS: The findings of this study demonstrate that paternal stress can impact offspring learning and memory.

PMID:34428362 | DOI:10.1515/jbcpp-2020-0183

PLoS One. 2021 Aug 24;16(8):e0256636. doi: 10.1371/journal.pone.0256636. eCollection 2021.

ABSTRACT

INTRODUCTION/BACKGROUND: Dengue fever remains a public health threat despite being preventable. A solution to the constant problem of dengue infection will require active intervention and a paradigm shift. Assessing perceived risk and correlating it with the attitude and practice of the community will help in designing appropriate measures. However, possible instruments for these assessments come with limitations.

OBJECTIVE: The aim is to develop and validate a new scoring-based questionnaire, using dual statistical approaches to measure risk perception, attitude, and practices (RPAP) related to dengue in the community.

METHODS: The RPAP questionnaire was developed bilingually using the International Society for Pharmacoeconomics and Outcome Research (ISPOR) guidelines. Content analysis was reviewed scrupulously by four expert panels. The initial 35-item scale was tested among 253 Malaysian respondents recruited non-probabilistically via multiple online platforms. Two statistical methods were employed to measure the construct validity: Exploratory Factor Analysis (EFA) as part of the Classical Test Theory (CTT) measurement, while Rasch Measurement Analysis (Rasch) was performed for the Item Response Theory (IRT) measurement. All results were cross-validated with their counterpart to ensure stability. Confirmatory Factor Analysis (CFA) was used to obtain a model fit index.

RESULTS: 29 questions were retained after the final analysis. Both EFA and Rasch analysis detect multidimensionality. Nine latent factors were extracted from EFA, while only eight factors remained in the final model following CFA: 1) perceived susceptibility; 2) perceived severity; 3) perceived barrier; 4) perceived benefit; 5) cues to action; 6) self-efficacy; 7) attitude; and 8) practice. All items had adequate factor loadings and showed good internal consistency. The final model after CFA achieved a good fit with an RMSEA value of 0.061, SRMR of 0.068, PNFI of 0.649, and GFI of 0.996.

CONCLUSION: The RPAP questionnaire contains 29 items and is a reliable and accurate psychometric instrument for measuring the risk perception of dengue fever, attitude, and practice of the community in dengue prevention. The Rasch measurement provides additional rigour to complement the CTT analysis. This RPAP questionnaire is suitable for use in studies related to dengue prevention in the community.

PMID:34428257 | DOI:10.1371/journal.pone.0256636