Pairwise Tests Research Articles

Discrepancies in the occlusal devices designed by an experienced dental laboratory technician and by 2 artificial intelligence-based automatic programs

Artificial intelligence (AI) models have been developed for different applications, including the automatic design of occlusal devices; however, the design discrepancies of an experienced dental laboratory technician and these AI automatic programs remain unknown. The purpose of this in vitro study was to compare the overall, intaglio, and occlusal surface discrepancies of the occlusal device designs completed by an experienced dental laboratory technician and two AI automatic design programs. Virtually articulated maxillary and mandibular diagnostic casts were obtained in a standard tessellation language (STL) file format. Three groups were created depending on the operator or program used to design the occlusal devices: an experienced dental laboratory technician (control group) and two AI programs, namely Medit Splints from Medit (Medit group) and Automate from 3Shape A/S (3Shape group) (n=10). To minimize the discrepancies in the parameter designs among the groups tested, the same printing material and design parameters were selected. In the control group, the dental laboratory technician imported the articulated scans into a dental design program (DentalCAD) and designed a maxillary occlusal device. The occlusal device designs were exported in STL format. In the Medit and 3Shape groups, the diagnostic casts were imported into the respective AI programs. The AI programs automatically designed the occlusal device without any further operator intervention. The occlusal device designs were exported in STL format. Among the 10 occlusal designs of the control group, a random design (shuffle deck of cards) was used as a reference file to calculate the overall, intaglio, and occlusal discrepancies in the specimens of the AI groups by using a program (Medit Design). The root mean square (RMS) error was calculated. Kruskal-Wallis, and post hoc Dwass-Steel-Critchlow-Fligner pairwise comparison tests were used to analyze the trueness of the data. The Levene test was used to assess the precision data (α=.05). Significant overall (P<.001), intaglio (P<.001), and occlusal RMS median value (P<.001) discrepancies were found among the groups. Significant overall RMS median discrepancies were observed between the control and the Medit groups (P<.001) and the control and 3Shape groups (P<.001). Additionally, significant intaglio RMS median discrepancies were found between the control and the Medit groups (P<.001), the Medit and 3Shape groups (P<.001), and the control and 3Shape groups (P=.008). Lastly, significant occlusal RMS median discrepancies were found between the control and the 3Shape groups (P<.001) and the Medit and 3Shape groups (P<.001). The AI-based software programs tested were able to automatically design occlusal devices with less than a 100-µm trueness discrepancy compared with the dental laboratory technician. The Levene test revealed significant overall (P<.001), intaglio (P<.001), and occlusal (P<.001) precision among the groups tested. The use of a dental laboratory technique influenced the overall, intaglio, and occlusal trueness of the occlusal device designs obtained. No differences were observed in the precision of occlusal device designs acquired among the groups tested.

THE EFFECT OF HEALTH AND EDUCATION EXPENDITURES ON THE EMPLOYMENT: EMPIRICAL EVIDENCE FROM TÜRKİYE

This research delves into the influence of human capital investments on employment in Türkiye between 2000 and 2021. We first employ the Autoregressive Distributed Lag (ARDL) method to assess both the short and long-term impacts of human capital investments on employment. Then, the Pairwise Granger Causality test is applied to explore the causality among the variables. According to the long run coefficient, a 1% rise in government education and health expenditures and GDP growth rate leads to a 1.27%, 1.17% and 0.76% increase in employment in Türkiye, respectively. Additionally, The Pairwise Granger Causality test results show that government education expenditure on human capital influences employment in Türkiye and vice versa as well as a causal relation between the employment rate and inflation rate. In conclusion, Türkiye should increase its expenditure on health and education as these investments serve as a vital role in enhancing the level of human capital and welfare of the population.

Reconsidering agricultural credits and agricultural production nexus from a global perspective

AbstractAccess to credit has been a key component in protecting a country's agriculture sector against uncertainties and climate‐related shocks. Agricultural credits may also increase both agribusiness sectors' and farming‐related commercial activities' exposure to world markets. This study aims to investigate agricultural credits' short‐run and long‐run effects on agricultural production using control variables such as foreign direct investments, inflation rate, and government expenditures. We found that credits to agriculture affect value‐added agriculture positively in the long‐run; specifically, when agricultural credits increase by 1%, value‐added agriculture will increase by 0.19%; that is, an increase in credits to the agricultural sector leads to a significant increase in value‐added agriculture, while FDI and government size both reduce agricultural value‐added across countries. The findings of the pairwise causation test show that bidirectional causal links exist among almost all variables, validating feedback among agricultural value‐added, credit to agriculture, FDI, government expenditures, and inflation.

Effect of Trade Openness and Agriculture on Tax Revenue Performance in Kenya

Purpose: Taxes play a critical role for most governments around the world in funding investments in capital, infrastructure and the delivery of essential services. The study therefore sought to examine the effect of trade openness and agriculture on tax revenue performance in Kenya.&#x0D; Methodology: The study adopted correlational research design, Vector Error Correction Model (VECM) mechanism and Granger causality test to establish the relationship between the study variables. The choice of the VECM was influenced by its ability to estimate both short run and long run relationships. The theoretical framework of the study followed Heller’s neoclassical maximization utility approach. Annual time series data for the study were sourced from the World Bank Development Indicators for the period 1980-2020.&#x0D; Results: The study findings established that in the long-run agriculture share (-0.64, t-statistics = 14.57) and trade openness (-0.08, t-statistics = 3.88) have negative and significant effect on tax revenue performance in Kenya. The Pairwise Granger Causality test results indicated unidirectional causality running from tax revenue performance to trade openness. This suggests that tax rates have effect on trade openness in Kenya.&#x0D; Unique Contribution to Theory, Policy and Practice: The study adds to literature by proving the Arthur’s Laffer curve theory which advocates for lowering tax rates in order to boost productivity and encourage expansion of corporation. The findings of the study may provide the National Treasury with foundation for policy formulation and analytical framework for estimating the associated tax revenue with variables under consideration in this study. The study may be of importance to KRA in determining appropriate tax rates that are favorable in boosting revenue mobilization.

The influence of meat consumption on greenhouse gas emissions in Argentina

This research investigated the empirical relationship between meat consumption and greenhouse gas (GHG) emissions in Argentina. The Autoregressive Distributed Lag (ARDL) and Dynamic Ordinary Least Squares (DOLS) techniques were employed to analyze time-series data from 1990 to 2020. The ARDL bound test demonstrates the long-term cointegration of all variables. According to the DOLS model, a 1 % increase in meat consumption increases GHG emissions by 0.91 % over the long term. Moreover, a 1 % increase in economic growth and energy consumption will increase Argentina's GHG emissions by 1.15 % and 1.32 %, respectively. The fully modified least squares (FMOLS) method was used to assess the reliability of the DOLS results. Additionally, the pairwise Granger causality test was employed to assess the causal relationship between the variables. The empirical findings indicate that the Argentine livestock industry can become more environmentally friendly with proper policy formulation and implementation.

Do Spot, Futures, and Options Markets Exhibit Price and Volatility Interdependence? Evidence from India

This paper analyses the price- and volatility-based interdependency among spot, futures, and options markets in a unified framework. The paper utilizes the vector error correction model generated under the TGARCH framework, the conventional pair-wise Granger causality test, the block exogeneity and vector Granger causality test, and Schwartz–Szakmary’s factor weights to decipher the price interdependence. The paper also uses the DCC-GARCH model to examine the existence of time-varying conditional correlation in volatility. The study finds evidence of the dependency among these three markets with a stronger leading role of spot against futures and options and significant positive/(negative) influence of the previous day’s spot/(futures) price change on options’ price change. Further, the asymmetric impact of price changes on conditional volatility is observed in the case of the spot and futures market. The results also exhibit the existence of time-varying conditional correlation among these markets with spillover effect.

Testing Unemployment–Entrepreneurship Nexus in Namibia Using the Schumpeterian Approach

This study uses time series data from the World Bank database to examine the relationship between unemployment and entrepreneurship in Namibia. We applied the Augmented Dickey–Fuller and Phillips–Perron tests for unit root testing and found all the variables to be stationary after the first difference. Given that, we employed the Johansen–Juselius test to measure cointegration, which revealed the absence of long-run relationships between the variables. Hence, we performed a Vector Autoregressive model to estimate the short-run relationships and found that Namibia exhibits both the refugee and Schumpeter effects. Finally, we measured the direction of causality using the Pairwise Granger causality test, and the results revealed that none of the variables Granger causes the other, implying that they are all independent of each other. This implies that the significance of entrepreneurship in addressing unemployment in Namibia is limited in the long run, mostly owing to the absence of sustainable business ventures. Therefore, we recommend prioritizing the development of policies to tackle unemployment through sustainable entrepreneurship.

Association of Discharge Location Following Pediatric Tracheostomy with Social Determinants of Health: A National Analysis.

To evaluate the breakdown of discharge locations among pediatric tracheostomy patients and determine the impact of demographic variables and social determinants of health. Retrospective review of the 2016 and 2019 Healthcare Cost and Utilization Project Kids' Inpatient Database (HCUP KID). A total of 4000 United States community hospitals, defined as short-term, non-Federal, general, and specialty hospitals. ICD-10-PCS, ICD-10 CM codes, and HCUP data elements were selected for patients and variables of interest. Bivariate comparisons were performed using Rao-Scott Chi-square tests; significance levels in post hoc pairwise testing were adjusted using Bonferroni adjustment. Multinomial generalized logistic regression models were used to determine the average annual odds ratio (OR) of 3 dispositions at discharge relative to discharge home for self-care. Patients aged 11-17, patients from large metropolitan areas, and patients of "Other" race have an increased odds of discharge to a short- or long-term care facility (all P < .001). Weekend admissions, nonelective admissions, patients in Northeast hospitals, and patients at urban nonteaching hospitals are also more likely to be discharged to a short- or long-term care facility (all P < .001). Mean and median total costs of admission were $424,387 and $243,479, respectively, with a median total charge of $854,499. Among pediatric tracheostomy patients, demographic factors that affect discharge disposition include age, community type, and race, and significant hospital factors include day and type of admission, geographic region, and hospital type. Hospitalizations are associated with high overall costs and charges to the patient, which are increasing over time.

Pregabalin versus Gabapentin Efficacy in the Management of Neuropathic Pain Associated with Failed Back Surgery Syndrome.

Failed back surgery syndrome (FBSS) is a common long-term complication following spine surgeries characterized by chronic persistent pain; different strategies of management were employed to deal with it. This clinical trial aims to compare the efficacy of Pregabalin and Gabapentin in the management of this condition. A double-blind, randomized, comparative study (clinical trial registry NCT05324761 on 11th April 2022) with two parallel arms with Pregabalin and Gabapentin were used in arms one and two, respectively. Visual analog scale was used for basal and endpoint assessment of pain. T-test and analysis of covariance were used to deal with different variables. A pairwise test was used to compare pairs of means. Of 66 patients referred to the trial, 64 were eligible, with 60 patients completing the 30 days trial. Both pregabalin and gabapentin effectively reduce pain, with significant p-values of 0.001 for each group. However, the pregabalin group was superior to gabapentin in pain reduction (p=0.001). Gender was an insignificant factor (p=0.574 and p=0.445 for the pregabalin and gabapentin groups, respectively, with a non-significant reduction (p=0.393) for both groups in total. Location of stenosis before surgery and type of surgery performed show non-significant effect on pain reduction for both groups. Both pregabalin and gabapentin effectively and safely relieve neuropathic pain associated with FBSS; pregabalin was significantly more effective irrespective of the patients' gender.

How to lead on carbon neutrality through sustainable development: A perspective on renewable energy, Information and Communication Technology (ICT), and logistics networks.

In the face of intensifying climate change-induced environmental problems, understanding the causal relationship between carbon dioxide (CO2) emissions and socioeconomic factors is crucial for achieving sustainable development. This study investigates how the causal relationships between renewable energy, information and communication technology (ICT), logistics networks, economic growth, industrialization, and energy intensity impact sustainable development using a panel dataset drawn from 104 countries and covering 2006 to 2019. Methodologically, panel unit root, panel co-integration, and Granger causality tests are employed as robust econometric techniques. The results of the panel unit root and co-integration tests confirm the stationarity of the variables and reveal significant long-term relationships among them throughout the empirical analysis period. Notably, the panel FMOLS and DOLS estimates indicate a positive effect of RE and ICT on reducing CO2 emissions, whereas GDP and energy intensity have a negative impact on CO2 emissions reduction. Moreover, the pairwise Granger causality test findings indicate bidirectional causal relationships between RE and CO2, IND and CO2, ICT and RE, IND and RE, GDP and ICT, as well as IND and ICT. The study recommends providing policy support, including for technological development and innovation, towards establishing a system that fosters sustainable development.

Unpacking the Impact of Early Adverse Childhood Experiences on Early Onset of Sexual Intercourse Among an Urban Birth Cohort of Early Adolescents

PurposeEarly adverse childhood experiences (ACEs) predict early onset of sexual intercourse. However, patterns of ACEs identified using latent class analysis (LCA) and their links to early sexual intercourse have been less examined. In this study, we apply LCA to identify ACEs profiles at age five and to examine whether these profiles differentially predict adolescents' sexual initiation. MethodsWe analyzed data obtained from the Future of Families and Child Wellbeing Study for 3,185 participants (male = 1,638; female = 1,547). This included parental/caregivers' reports of 10 types of ACEs when participants were on average at age five and youth self-report data on sexual intercourse before or at age 15. We used LCA to classify the participants into subgroups and multinomial logistic regressions to examine differences in early sexual initiation among the ACEs subgroups. ResultsLCA showed evidence of four classes for both genders: low adversity (51.8%), socioeconomic adversity (32.0%), family dysfunction (12.0%), and abuse (4.2%). We found class membership differences in early sexual intercourse in all three adversity classes compared to the low adversity group. Pairwise comparison tests further revealed that adolescents in the family dysfunction class had lesser odds of engaging in early sexual intercourse than their counterparts in the socioeconomic adversity and abuse classes. DiscussionOur findings suggest that LCA could help identify meaningful and distinctive child adversity patterns while accounting for the co-occurrence of ACEs. This is particularly helpful in evaluating who might be at greatest health risk which can further inform more effective and targeted interventions.

Deciphering migraine pain mechanisms through electrophysiological insights of trigeminal ganglion neurons

Migraine is a complex neurological disorder that affects millions of people worldwide. Despite extensive research, the underlying mechanisms that drive migraine pain and related abnormal sensation symptoms, such as hyperalgesia, allodynia, hyperesthesia, and paresthesia, remain poorly understood. One of the proposed mechanisms is cortical spreading depression (CSD), which is believed to be involved in the regulation of trigeminovascular pathways by sensitizing the pain pathway. Another mechanism is serotonin depletion, which is implicated in many neurological disorders and has been shown to exacerbate CSD-evoked pain at the cortical level. However, the effects of CSD and serotonin depletion on trigeminal ganglion neurons, which play a critical role in pain signal transmission, have not been thoroughly studied. In this study, we aimed to investigate the association between CSD and serotonin depletion with peripheral sensitization processes in nociceptive small-to-medium (SM) and large (L) -sized trigeminal ganglion neurons at the electrophysiological level using rat models. We divided the rats into four groups: the control group, the CSD group, the serotonin depletion group, and the CSD/serotonin depletion group. We induced CSD by placing KCl on a burr hole and serotonin depletion by intraperitoneal injection of PCPA (para-chlorophenoxyacetic acid). We then isolated trigeminal ganglion neurons from all groups and classified them according to size. Using patch-clamp recording, we recorded the excitability parameters and action potential (AP) properties of the collected neurons. Our results showed that in SM-sized trigeminal ganglion neurons, the CSD-SM and CSD/serotonin depletion groups had a higher positive resting membrane potential (RMP) than the control-SM group (p = 0.001 and p = 0.002, respectively, post-hoc Tukey’s test). In addition, the gap between RMP and threshold in the CSD-SM group was significantly narrower than in the control-SM group (p = 0.043, post-hoc Tukey’s test). For L-sized neurons, we observed prolongation of the AP rising time, AP falling time, and AP duration in neurons affected by CSD (p < 0.05, pairwise comparison test). In conclusion, our study provides new insights into the underlying mechanisms of migraine pain and abnormal somatosensation. CSD and serotonin depletion promote the transmission of pain signals through the peripheral sensitization process of nociceptive small-to-medium-sized trigeminal ganglion neurons, as well as nociceptive and non-nociceptive large-sized trigeminal ganglion neurons.

Effect of print orientation, storage conditions, and storage time on intaglio surface accuracy of implant surgical guides fabricated by using a stereolithography technology

The accuracy of printed implant surgical guides can be affected by different factors that negatively impact the planned implant position. How print orientation, storage time, and conditions influence manufacturing accuracy remains uncertain. The purpose of this in vitro study was to evaluate the influence of print orientation, storage conditions, and storage time on the intaglio surface accuracy of implant surgical guides manufactured by using a stereolithography (SLA) printer. A tooth-supported maxillary implant surgical guide design (control file) was used to fabricate the specimens (N=40, n=10). Four groups were created based on the print orientation used: 0 (Group 0), 45 (Group 45), 70 (Group 70), and 90 degrees (Group 90). The specimens were fabricated using an SLA printer (Form 3B+) and a biocompatible dental resin (Surgical Guide Resin V1) following the manufacturer's recommended protocol. Each group was divided into 2 subgroups based on the storage conditions: light (L subgroup) and dark (D subgroup) settings. Each specimen was digitized by using a desktop scanner (Medit T710) at days 0, 1, 7, and 14. The control file and each digitized specimen were superimposed by using the best-fit technique with a metrology program (Geomagic Control X). The root mean square (RMS) error was used to calculate the discrepancies between the control files and specimen files. Three-way ANOVA and pairwise comparison Tukey tests were used to analyze trueness. The Levene test was used to assess precision (α=.05). Significant trueness discrepancies were found among the groups tested (P<.001), but no significant differences were found among the subgroups (P=.100) and the storage times analyzed (P=.609). Additionally, the Tukey test showed significant RMS error mean value discrepancies between Group 0 and Group 45 (P<.001), Group 0 and Group 90 (P<.001), Group 45 and Group 70 (P<.001), and Group 70 and Group 90 (P<.001). The Levene test revealed significant SD discrepancies among the groups tested (P<.05). The trueness and precision of the intaglio surface of the implant surgical guides manufactured by using the printer and material tested were affected by the print orientation. However, storage conditions over a 14-day period did not impact the intaglio accuracy of the specimens.

Composite endpoints, including patient reported outcomes, in rare diseases

BackgroundWhen assessing the efficacy of a treatment in any clinical trial, it is recommended by the International Conference on Harmonisation to select a single meaningful endpoint. However, a single endpoint is often not sufficient to reflect the full clinical benefit of a treatment in multifaceted diseases, which is often the case in rare diseases. Therefore, the use of a combination of several clinically meaningful outcomes is preferred. Many methodologies that allow for combining outcomes in a so-called composite endpoint are however limited in a number of ways, not in the least in the number and type of outcomes that can be combined and in the poor small-sample properties. Moreover, patient reported outcomes, such as quality of life, often cannot be integrated in a composite analysis, in spite of their intrinsic value.ResultsRecently, a class of non-parametric generalized pairwise comparisons tests have been proposed, which members do allow for any number and type of outcomes, including patient reported outcomes. The class enjoys good small-sample properties. Moreover, this very flexible class of methods allows for prioritizing the outcomes by clinical severity, allows for matched designs and for adding a threshold of clinical relevance. Our aim is to introduce the generalized pairwise comparison ideas and concepts for rare disease clinical trial analysis, and demonstrate their benefit in a post-hoc analysis of a small-sample trial in epidermolysis bullosa. More precisely, we will include a patient relevant outcome (Quality of life), in a composite endpoint. This publication is part of the European Joint Programme on Rare Diseases (EJP RD) series on innovative methodologies for rare diseases clinical trials, which is based on the webinars presented within the educational activity of EJP RD. This publication covers the webinar topic on composite endpoints in rare diseases and includes participants’ response to a questionnaire on this topic.ConclusionsGeneralized pairwise comparisons is a promising statistical methodology for evaluating any type of composite endpoints in rare disease trials and may allow a better evaluation of therapy efficacy including patients reported outcomes in addition to outcomes related to the diseases signs and symptoms.

The Impact of Excessive Weight on Breastfeeding Intention, Initiation, and Duration.

Background: Breastfeeding is widely recognized as the optimal feeding method for infants. However, breastfeeding goals are often unmet, especially in mothers with excessive weight. Potential factors associated with unmet goals could be disparities in care for women with higher body mass index (BMI) or mental health symptomology. Methods: Women enrolled in a longitudinal study were stratified by BMI into three groups: mothers with normal weight (18.5-24.9 kg/m2, n = 101), with overweight (25-29.9 kg/m2, n = 78), and with obesity (OB; 30-35 kg/m2, n = 48). Breastfeeding intention and standardized mental health questionnaires were administered at gestational weeks 12 and 36. The prevalence of initiation and duration of breastfeeding were determined based on self-reported breastfeeding start and end dates. Wilcoxon tests, pairwise proportion test, Cox proportional hazards regression, and linear regression were used. Results: Higher maternal weight status (OB) was significantly associated with lower breastfeeding intention and duration. As expected, higher breastfeeding intention scores were associated with significantly longer breastfeeding duration. Higher scores on the Beck Depression Inventory (BDI), associated with a greater number of depression symptoms, mediated the negative impact of weight status on breastfeeding intention. Conclusions: breastfeeding outcomes are negatively associated with maternal weight status and prenatal mental health with the relationship between the two being interconnected, despite subclinical scores on the BDI. Further research is needed to explore the role of mental health on breastfeeding outcomes. From these findings, targeted prenatal interventions for women with excessive weight and depressive symptoms would likely promote and improve breastfeeding outcomes. ClinicalTrials.gov: www.clinicaltrials.gov, ID #NCT01131117.

Long-Run and Short-Run Relationship Between Remittances and GDP Per Capita Growth, Evidence from Balkans Countries

This research study aims to explore the link between remittances as percentage of GDP and GDP per capita growth in six Balkans countries and Kosovo for the period 2007-2020. Panel cointegration based on dynamic ordinary least squares (DOLS) model was applied to check the magnitude of the potential long-run coefficients between the remittances as percentage of GDP and GDP per capita growth. In addition, the pairwise Granger causality tests were performed to capture the causal link among these two variables. The findings from the DOLS model indicate a positive association between remittance’s inflows and GDP per capita growth in the long-run. DOLS short–run relationships showed that the value of variable-remittances as percent of GDP has predictable properties to be a leading and lagging factor for these countries in the coming years. Results from the Granger causality confirm causality in unilateral direction running from remittance’s inflow to GDP per capita growth.

Climate change and sustainable agricultural growth in the sahel region: Mitigating or resilient policy response?

The aim of this study is to provide an empirical answer to the question of whether nexus exists between climate change and sustainable agricultural growth in nine (9) countries within the Sahel region between 1990 and 2020. The study utilized Panel ARDL and Pairwise Dumitrescu Hurlin Panel Causality Tests to arrive at the following conclusions; firstly, the climate change orchestrated by change in rainfall is a very prominent factor causing reduction in sustainable agricultural growth in the Sahel region. One way feedback relationship flows from sustainable agricultural growth to greenhouse gas emission. In the light of the above, this study recommends that, in addressing the adverse effects of change in rainfall on agricultural sustainability, the policymakers in the Sahel region in particular and Africa as a whole should embark on a policy mix by embanking on mitigating policy response towards ensuring sustainable agricultural production via irrigation which is the best mode of water provisions without causing negative spilliovers on the environment. Also, the policymakers should be proactive by embarking on policies and programs that would build the resilience and adaptation of the region ahead of the future adverse effects of agriculturally induced climatic change.

Yoğun Bakımlarda Çalışan Hemşirelerin Kişilik Özellikleri Açısından Deliryum Farkındalıkları ve Yönetimi

Objective: The study was carried out to determine delirium awareness and management among the nurses working in intensive care in terms of their personality traits.&#x0D; Method: It was a descriptive study. The study was carried out in a university hospital located in the western region of Turkey between February May 1 and May 31, 2019. The sample was composed of 84 nurses who were working in the adult intensive care unit. Data collection form, The Nurses’ Delirium Knowledge Questionnaire, and the Big Five Personality Trait Test were used to collect data. Data were evaluated with t-test, ANOVA, Mann-Whitney U, Kruskal-Wallis H, Bonferroni Corrected Pairwise Comparison Test, and Spearman Correlation coefficient using SPSS 24.0 package program.&#x0D; Results: The total mean personality score of the nurses was 158.38±14.32. The total delirium knowledge score of the participants was found to be 44.77±9.83. Knowledge score of the nurses regarding the definition of delirium was found to be negatively correlated with the personality trait of extraversion whereas their delirium sign/symptom scores were positively correlated with conscientiousness, agreeableness and total big five personality trait score. In addition, positive correlations were found between delirium management score and their conscientiousness, neuroticism, and big five personality trait scores and between their total delirium knowledge score and personality trait of conscientiousness (p

Influence of interdental spaces and the palate on the accuracy of maxillary scans acquired using different intraoral scanners.

To assess the influence of interdental spaces and scanning the palate on the accuracy of maxillary scans acquired using three intraoral scanners (IOSs). A virtual completely dentate maxillary cast without interdental spaces was obtained and modified to create 1, 2, and 3mm of interdental spacing between the anterior teeth. These three files (reference standard tessellation language files) were used to print three reference casts. The reference casts were scanned using three IOSs: TRIOS4, iTero Element 5D, and Aoralscan2. Three groups were created based on the interdental spaces: 0, 1, 2, and 3mm (n = 10). The groups were subdivided into two subgroups: no palate (NP subgroup) and palate (P subgroup). The reference STL files were used to measure the discrepancy with the experimental scans by calculating the root mean square (RMS) error. Three-way analysis of variance (ANOVA) and post hoc Tukey pairwise comparison tests were used to analyze trueness. The Levene test was used to analyze precision (α = 0.05). Trueness ranged from 91 to 139μm and precision ranged from 5 to 23μm among the subgroups tested. A significant correlation was found between IOS*group (p<0.001) and IOS*subgroup ( p<0.001). Tukey test showed significant trueness differences among the interdental spaces tested (p<0.001). The 1- and 2-mm groups obtained better trueness than the 0- and 3-mm groups (p<0.001). An 11μm mean trueness discrepancy was measured among the different interdental space groups tested. The P subgroups demonstrated significantly higher trueness when compared to the NP subgroups (p<0.001). The discrepancy between the maxillary scans with and without the palate was 4μm. Significant precision discrepancies were found (p = 0.008), with the iTero group showing the lowest precision. Interdental spaces and incorporation of the palate on maxillary intraoral scans influenced trueness and precision of the three IOSs tested. However, the scanning discrepancy measured may be of no clinical relevance.

Influence of the postpolymerization type and time on the flexural strength and dimensional stability of 3D printed interim resins

Statement of problemThe mechanical strength of 3-dimensionally (3D) printed interim resins is unclear but influenced by printing parameters. Evidence regarding standardization of the postpolymerization type and time for 3D printed interim resins is sparse. PurposeThe purpose of this in vitro study was to evaluate the influence of postpolymerization type and time on flexural strength and dimensional stability of 3D printed resins for interim restorations. Material and methodsA total of 288 bars were 3D printed (Form 2; Formlabs, stereolithography—SLA, 50 µm, 30 degrees), (25×2×2 mm; International Organization for Standardization—ISO 4049:2019) abraded and randomly divided into 9 groups (n=30) according to postpolymerization (Ultraviolet device—UV; Microwave with water—MWA; Microwave without water—MW) and time (15, 20, and 30 minutes for UV; and 5, 8, and 10 minutes for MW and MWA). Each bar was then measured with digital calipers at 11 points for length, thickness, and width before and after postpolymerization to analyze dimensional stability. The flexural strength was then measured (σ; 980.6 N, 1 mm/minute) and the fractured surfaces were analyzed with scanning electron microscopy. The σ (MPa) data were evaluated by using a 2-way analysis of variance (ANOVA) and the Tukey honestly significant difference (HSD) pairwise comparisons test (α=.05). Dimensional stability data (mm) were analyzed by using the Kruskal-Wallis test and Dwass-Steel-Critchlow-Fligner multiple comparisons. The Weibull analysis was performed with σ data. ResultsThe 2-way ANOVA revealed that all factors and their interaction were significant for σ (P<.001). The UV groups presented the highest σ values, being statistically higher than all MW and MWA groups. The Weibull analysis revealed that postpolymerization UV groups found the highest values regarding the characteristic strength, although the MW 8-minute group (13.71) found the highest value for the Weibull modulus. Furthermore, the Kruskal-Wallis test revealed that only the postpolymerization factor was significant for dimensional stability (P<.001). The postpolymerization microwave groups found greater expansion variations at all times, with the MW 8-minute group (0.78 ±0.54) presenting the greatest variation in dimensional stability. ConclusionsUV was determined to be the most suitable type of postpolymerization for interim printed resin among the postpolymerization methods, regardless of the application time. The postpolymerization MW groups found greater variations in dimensional stability.