scholarly journals Transmittance of lithium disilicate ceramic of different thicknesses and opacities with different curing units

2021 ◽  
Vol 34 (2) ◽  
pp. 143-148
Author(s):  
Martín García-Cuerva ◽  
Agustina Boaventura-Dubovik ◽  
María Iglesias
Keyword(s):  
Repeated Measures ◽  
Medical Instrument ◽  
Multiple Comparisons ◽  
Lithium Disilicate ◽  
Repeated Measures Anova ◽  
Tukey Test ◽  
Transmitted Energy

The aim of this study was to evaluate the amount of radiating energy transmitted through lithium disilicate discs of different thicknesses and opacities with different curing units (CU). Discshaped specimens 8 mm in diameter and 1.5 mm or 0.7 mm thick were designed with Zbrush® and Cura 3D® software, milled from HT and MO IPS e-maxCAD blocks (Ivoclar Vivadent) with Ceramill Mikro 4 (Amann Girrbach, Austria) and processed according to manufacturer instructions. Thickness was checked with a Mitutoyo (México) caliper. Four groups (n=4) were formed: G1(HT/1.5 mm), G2(MO/1.5 mm), G3(HT/0.7 mm) y G4(MO/0.7 mm), and the effect of three CUs: Coltolux (ColteneWhaledent), LED.C, (Woodpecker Medical Instrument Co.Ltd) and Deepcure L(3M-ESPE) was tested Measurements were taken with a halogen and LED radiometer (Woodpecker® LM-1-Guilin Woodpecker Medical Instrument Co.Ltd) after applying the guide of each CU directly on the reading window (d) and after interposing each of the specimens. The ratio of transmitted energy was determined in each case and data was analyzed with repeated measures ANOVA and Tukey test for multiple comparisons. LED.C: d:1600 mW/cm2, G1: 0.31(0.00), G2: 0.14(0.00) G3: 0.54(0.01), G4: 0.38(0.01); Deepcure L: d:1500 mW/cm2, G1: 0.34(0.01), G2: 0.20(0,00), G3: 0.56(0.01), G4: 0.41(0.02); Coltolux: d:1275 mW/cm2, G1: 0.44(0.01), G2: 0.24(0,00), G3: 0.65(0.01), G4: 0.47(0,00). Statistically significant differences were found among the curing units (P<0.001) and for the interaction CU-thickness (P<0.001) CU-opacity (P=0.023). Within the conditions of this study, the ratio of light transmitted through lithium disilicate structures is related to their thickness and opacity, and to the curing unit employed.

scholarly journals Decomposition Rate, pH, and Enamel Color Alteration of At-Home and In-Office Bleaching Agents

2019 ◽  
Vol 30 (4) ◽  
pp. 385-396 ◽  
Author(s):  
Vanessa Cavalli ◽  
Bruna Guerra da Silva ◽  
Sandrine Bittencourt Berger ◽  
Fabiano Carlos Marson ◽  
Cinthia Pereira Machado Tabchoury ◽  
...  
Keyword(s):  
Decomposition Rate ◽  
Repeated Measures ◽  
Light Irradiation ◽  
Alkaline Ph ◽  
Carbamide Peroxide ◽  
Treatment Control ◽  
Repeated Measures Anova ◽  
Tukey Test ◽  
Color Alteration ◽  
At Home

Abstract This study evaluated the decomposition rate (DR), pH, enamel color alteration (DE) and whiteness index (DWI) promoted by at-home and in-office bleaching. Enamel surface was submitted to (n=10): at-home (10%, 15%, 20% carbamide peroxide - CP, 6% hydrogen peroxide -HP) and three 35% HP agents with light irradiation (LED, laser, and halogen) or no treatment (control). The DR and pH of agents were measured after 0, 2, 4, 6 and 8 h (at-home) or after 5, 15, 20, 30 and 40 min (in-office). Color parameters (L*, a*, b*, DE, DWI) were determined at baseline and after bleaching. DR, pH, L*, a*, b* data were analyzed by one-way (at-home) or two-way (in-office) repeated measures ANOVA and Tukey test. DE and DWI, by one-way (at-home) or two-way (in-office) ANOVA and Tukey test. DR of at-home agents was similar after 6 and 8 h (p>0.05), with pH close to neutral (6.5 to 6.9, CP) or acid 5.9 (6% HP). From 4 to 8 h, DE was higher for 15% and 20% CP compared with 10% CP (p<0.05). After 40 min, DR of 35% HP agents was similar and all exhibited significant DE in one application (p<0.05), regardless light irradiation. DWI indicated whitening effect with no differences among groups (p>0.05). One 35% HP showed alkaline pH, and the others, pH < 5.5. At-home agents could be applied for 2 h (15%, 20% CP, 6% HP) and 4 h (10% CP) and the in-office agents, up to 40 min in one application, without light.

One Size Fits All?

Methodology ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Manuel C. Voelkle ◽  
Patrick E. McKnight
Keyword(s):  
Repeated Measures ◽  
Structural Equation ◽  
Type I Error ◽  
Equation Modeling ◽  
Type I ◽  
Finite Sample ◽  
Traditional Methods ◽  
Repeated Measures Anova ◽  
Special Cases ◽  
Latent Curve

The use of latent curve models (LCMs) has increased almost exponentially during the last decade. Oftentimes, researchers regard LCM as a “new” method to analyze change with little attention paid to the fact that the technique was originally introduced as an “alternative to standard repeated measures ANOVA and first-order auto-regressive methods” (Meredith & Tisak, 1990, p. 107). In the first part of the paper, this close relationship is reviewed, and it is demonstrated how “traditional” methods, such as the repeated measures ANOVA, and MANOVA, can be formulated as LCMs. Given that latent curve modeling is essentially a large-sample technique, compared to “traditional” finite-sample approaches, the second part of the paper addresses the question to what degree the more flexible LCMs can actually replace some of the older tests by means of a Monte-Carlo simulation. In addition, a structural equation modeling alternative to Mauchly’s (1940) test of sphericity is explored. Although “traditional” methods may be expressed as special cases of more general LCMs, we found the equivalence holds only asymptotically. For practical purposes, however, no approach always outperformed the other alternatives in terms of power and type I error, so the best method to be used depends on the situation. We provide detailed recommendations of when to use which method.

Time of imagery’s effect on performance and self-efficacy in college baseball players

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Colton Haight ◽  
Sandra Moritz ◽  
Tanis Walch
Keyword(s):  
Self Efficacy ◽  
Repeated Measures ◽  
Group Interaction ◽  
Physical Effect ◽  
Baseball Players ◽  
Repeated Measures Anova ◽  
Significant Time ◽  
Imagery Group ◽  
College Baseball ◽  
Group 2

AbstractThe relationships among the time of imagery use on performance and self-efficacy in college baseball players during a hitting task was examined. Participants (n=24) were randomly assigned to one of three imagery conditions: (a) before practice, (b) during practice, (c) after practice. A one-shot MG-M imagery intervention was used. Results from a 3 (imagery group) ×2 (pretest and posttest) repeated measures ANOVA showed only a significant time by imagery group interaction for self-efficacy (F (2, 21)=4.67, p<0.05). These findings suggest that imagery had a stronger psychological effect than physical effect.

scholarly journals Differences in Graphomotor Skills by the Writing Medium and Children’s Gender

2021 ◽  
Vol 11 (4) ◽  
pp. 162
Author(s):  
Boram No ◽  
Naya Choi
Keyword(s):  
Preschool Children ◽  
Repeated Measures ◽  
Repeated Measures Anova ◽  
Surface Textures ◽  
Young Learners ◽  
And Gender ◽  
Print Size ◽  
Writing Practice ◽  
Pressure Analysis

Factors of graphomotor skills may serve as indicators to determine a writer’s handwriting proficiency or acclimation to different writing surface textures. This study examines differences in children’s graphomotor skills based on types of writing medium and gender. Participants were 97 six-year-old Korean preschool children who had not received formal writing training prior to the study. Writing tasks were completed on a tablet screen and paper. Writing samples were analyzed using the Eye and Pen software to investigate spatial, temporal, and pressure exertion exhibited during the writing tasks. A repeated measures ANOVA revealed differences in graphomotor skills such as print size, writing speed, and writing pressure. Writing on a tablet screen decreased clarity of writing; print size and speed increased as the stylus slides across the tablet surface with relatively less friction, thereby decreasing the exertion of writing pressure. Analysis of writing differences according to gender indicated that boys generated larger print sizes than girls. Results suggest that while simple writing tasks may be feasible on the tablet screen, providing children with a larger writing medium and encouraging larger print sizes for writing practice, especially for boys, may be beneficial in the development of graphomotor skills among young learners.

scholarly journals Effects of Different Polishing Protocols on Lithium Disilicate Ceramics

2015 ◽  
Vol 26 (5) ◽  
pp. 478-483 ◽  
Author(s):  
Tânia Mara da Silva ◽  
Ana Carolina Rodrigues Danzi Salvia ◽  
Rodrigo Furtado de Carvalho ◽  
Eduardo Galera da Silva ◽  
Clóvis Pagani
Keyword(s):  
Surface Roughness ◽  
Lithium Disilicate ◽  
Sem Analysis ◽  
Surface Treatments ◽  
Control Group ◽  
Morphological Pattern ◽  
Tukey Test ◽  
Polishing Procedures ◽  
Diamond Paste

Abstract: The aim of this study was to evaluate the effect of different polishing protocols on surface roughness and morphology of lithium disilicate ceramics (IPS e.max CAD). Fifty ceramic bars (2.0x3.0x2.5 mm) were produced and randomly divided into five groups (n=10), according to surface treatments: C: Control; Cer: Ceramaster (60 s); CW: cloth wheel with large-grit diamond (30 s) + cloth wheel with fine-grit diamond paste (30 s); E: grey Exa-Cerapol (20 s) + pink Exa-Cerapol (20 s) + Cerapol Super (20 s); F: Felt wheel with large-grit diamond paste (30 s) + Felt wheel with fine-grit diamond paste (30 s). The samples were evaluated quantitatively for surface roughness (Ra) and qualitatively by SEM, at different moments: initial (prior to roughening), after roughening and after polishing procedures. Ra means were submitted to two-way ANOVA and Tukey test (p<0.05). After the different polishing protocols, no statistically significant differences were observed between the Cer and E groups (p=0.6347), E and CW groups (p=0.1366), and CW and FW groups (p=0.5433). Comparing different stages in the same group, it was possible to observe that CW (p<0.0001) and FW groups (p<0.0001) showed significant differences. SEM analysis revealed that both Cer and E groups exhibited a surface morphological pattern similar to that of control group. All polishing systems were effective in reducing the surface roughness of the studied ceramic type.

scholarly journals Microhardness evaluation of root dentin after using resin sealer solvents

2021 ◽  
Vol 15 (4) ◽  
pp. 256-261
Author(s):  
Gamze Nalci ◽  
Tayfun Alaçam ◽  
Bülent Altukaynak
Keyword(s):  
Repeated Measures ◽  
Saline Solution ◽  
Prolonged Exposure ◽  
Repeated Measures Anova ◽  
Ultrasonic Agitation ◽  
Gutta Percha ◽  
Before And After ◽  
Root Dentin ◽  
Substantial Decline ◽  
Hardness Values

Background. This study aimed to assess the effects of methyl ethyl ketone (MEK) and ethyl acetate (EA) on dentin microhardness, used as resin sealer solvents. Methods. Eighty halves of single-rooted teeth were randomly divided into four groups to apply MEK, EA, chloroform, or saline solution. Vickers hardness values were measured for three root levels before and after the direct application of solvents for 5 and 15 minutes or a 1-minute application with ultrasonic agitation. The results were analyzed using repeated-measures ANOVA, and adjustments were made for comparisons with Bonferroni tests. Results. The dentin microhardness decreased in all the solvent groups (P<0.05). The changes in microhardness increased with prolonged exposure times, except for the saline solution group. Chloroform exhibited the most significant decrease in value. Furthermore, ultrasonic agitation elicited a more substantial decline in values. Conclusion. MEK and EA might be preferred over chloroform as a solvent for resin sealers because they offer an attenuated decrease in dentin microhardness and do not have gutta-percha-dissolving properties.

scholarly journals Analyzing randomized controlled interventions: Three notes for applied linguists

2015 ◽  
Vol 5 (1) ◽  
pp. 135-152 ◽  
Author(s):  
Jan Vanhove
Keyword(s):  
Repeated Measures ◽  
Intervention Studies ◽  
Mixed Effects ◽  
Analysis Of Covariance ◽  
Cluster Randomization ◽  
Repeated Measures Anova ◽  
Randomized Controlled ◽  
Mixed Effects Modeling ◽  
Statistical Formalism ◽  
Relevant Covariates

I discuss three common practices that obfuscate or invalidate the statistical analysis of randomized controlled interventions in applied linguistics. These are (a) checking whether randomization produced groups that are balanced on a number of possibly relevant covariates, (b) using repeated measures ANOVA to analyze pretest-posttest designs, and (c) using traditional significance tests to analyze interventions in which whole groups were assigned to the conditions (cluster randomization). The first practice is labeled superfluous, and taking full advantage of important covariates regardless of balance is recommended. The second is needlessly complicated, and analysis of covariance is recommended as a more powerful alternative. The third produces dramatic inferential errors, which are largely, though not entirely, avoided when mixed-effects modeling is used. This discussion is geared towards applied linguists who need to design, analyze, or assess intervention studies or other randomized controlled trials. Statistical formalism is kept to a minimum throughout.

scholarly journals Αξιολόγηση της πρώιμης νευροεξελικτικής παρέμβασης στη νευροαναπτυξιακή πορεία πρόωρων νεογνών υψηλού κινδύνου

2012 ◽  
Author(s):  
Μαρία Κυριακίδου
Keyword(s):  
Repeated Measures ◽  
T Test ◽  
Repeated Measures Anova ◽  
Kolmogorov Smirnov ◽  
One Way Anova

Τα ποσοστά θνητότητας των υψηλού κινδύνου πρόωρων νεογνών έχουν σταθεροποιηθεί και συνεπώς η μελέτη των στρατηγικών μείωσης των υψηλών ποσοστών νευροαναπτυξιακών διαταραχών είναι απαραίτητη. Τα υψηλού κινδύνου πρόωρα νεογνά πρέπει να συμμετέχουν σε προγράμματα πρώιμης παρέμβασης από πολύ νωρίς, λόγω της αυξημένης πλαστικότητας του αναπτυσσόμενου εγκεφάλου. Παρόλα αυτά, η αποτελεσματικότητα της παρέμβασης σε όλα τα ΥΚ πρόωρα νεογνά δεν είναι ξεκάθαρη. Έχει αποδειχτεί, ότι οι πρώιμες αναπτυξιακές παρεμβάσεις που ξεκινούν μετά την έξοδο από το νοσοκομείο, βελτιώνουν τη γνωστική ανάπτυξη των νεογνών αλλά το αποτέλεσμα αυτό δε διατηρείται στη σχολική ηλικία. Η απόδειξη των επιδράσεων της πρώιμης παρέμβασης στην κινητική ανάπτυξη είναι ελλιπής. Επομένως, στόχος της παρούσας μελέτης ήταν να αξιολογήσει την επίδραση της πρώιμης παρέμβασης με τη μέθοδο NDT στη γνωστική και κινητική έκβαση ΥΚ πρόωρων νεογνών, μέχρι τη διορθωμένη ηλικία των 18 μηνών αλλά και να συσχετίσει νεογνικούς και περιγεννηρικούς παράγοντες με τη γνωστική και κινητική έκβαση. Στη μελέτη εισήχθησαν νεογνά με ΔΚ≤32 εβδομάδων και ΒΓ≤1500 γραμμαρίων. Αποκλείστηκαν, νεογνά με χρωματοσωμικές ανωμαλίες, μείζονες συγγενείς ανωμαλίες και γενετικά σύνδρομα. Επίσης, αποκλείστηκαν τα νεογνά που στη διορθωμένη ηλικία των 18 μηνών διαγνώστηκαν με εγκεφαλική παράλυση. Συνολικά, 147 νεογνά πληρούσαν τα κριτήρια εισαγωγής και εφαρμόστηκε η δοκιμασία ΤΙΜΡ στη ΔΗ των 38-41 εβδομάδων. Από αυτά, 73 τυχαιοποιήθηκαν στην ομάδα παρέμβασης και 74 στην ομάδα ελέγχου. Η ομάδα παρέμβασης ακολούθησε πρόγραμμα φυσικοθεραπείας με τη μέθοδο NDT με συχνότητα 2 φορές την εβδομάδα, για ένα έτος ενώ η ομάδα ελέγχου εφάρμοσε πρόγραμμα οδηγιών στο σπίτι 2 φορές την εβδομάδα, για ένα έτος. Στη στατιστική ανάλυση χρησιμοποιήθηκε το t-test, η one-way ANOVA, ο έλεγχος χ² κατά Pearson, repeated measures ANOVA και ο έλεγχος κατά Greenhouse-Geisser. Επιπρόσθετα, χρησιμοποιήθηκε ο έλεγχος Kolmogorov-Smirnov. Το ΒΓ και η ΔΚ των νεογνών στις δύο ομάδες ήταν 1325,18 (±368,46) γρ και 30,55 (±1,6) εβδ, αντίστοιχα, στην ομάδα παρέμβασης και 1440,18 (±293,61) και 30,76 (±1,6) στην ομάδα ελέγχου, αντίστοιχα. Η διαφορά δεν ήταν στατιστικά σημαντική. Οι δύο ομάδες ήταν συγκρίσιμες ως προς τους περιγεννητικούς και νεογνικούς παράγοντες . Οι 2 ομάδες αξιολογήθηκαν στη διορθωμένη ηλικία των 3, 6, 12 και 18 μηνών. Οι δύο ομάδες είχαν στατιστικά σημαντική διαφορά στη διορθωμένη ηλικία των 3, 12 και 18 μηνών στη γνωστική και κινητική έκβαση με την ομάδα παρέμβασης να υπερέχει. Στη διορθωμένη ηλικία των 18 μηνών, η ομάδα παρέμβασης σημείωσε μέση βαθμολογία 108,83 (±9,39) στη γνωστική κλίμακα και 109,01 (±10,30) στην κινητική ενώ η ομάδα ελέγχου 99,18 (±7,31) στη γνωστική και 98,81 (±8,91) στην κινητική κλίμακα της δοκιμασίας Bayley III. Η φυσικοθεραπεία (p<0,0001), η IVH (p<0,0001), η πολυδυμία (p=0,008), η ΝΕΚ (p=0,001) και η διάρκεια χορήγησης Ο₂ (p=0,008) επηρέασαν σημαντικά στη βαθμολογία της γνωστικής έκβασης των πρόωρων νεογνών στη διορθωμένη ηλικία των 18 μηνών. Η φυσικοθεραπεία (p<0,0001), ήταν ο μοναδικός παράγοντας που επηρέασε σημαντικά τη βαθμολογία της κινητικής έκβασης των πρόωρων νεογνών στη διορθωμένη ηλικία των 18 μηνών. Τα ΥΚΠΝ επωφελούνται από το πρόγραμμα πρώιμης παρέμβασης με τη μέθοδο NDT, διότι βελτιώνουν την κινητική και γνωστική τους έκβαση μέχρι τη διορθωμένη ηλικία των 18 μηνών. Ως εκ τούτου, συστήνεται η εφαρμογή της μεθόδου κατά τη διάρκεια του 1ου έτους ζωής ως προληπτικό πρόγραμμα θεραπείας στα ΥΚΠΝ. Αδιαμφισβήτητα, μεγαλύτερης διάρκειας μακροχρόνιες παρακολουθήσεις απαιτούνται για να επιβεβαιώσουν ή να απορρίψουν τη διατήρηση των αποτελεσμάτων στην προσχολική ή σχολική ηλικία. Συστήνεται, ο παράγοντας φυσικοθεραπευτική παρέμβαση να συνυπολογίζεται στις πολυπαραγοντικές αναλύσεις διότι οδηγεί σε αξιόπιστη ερμηνεία των αποτελεσμάτων που αφορούν την έκβαση.

scholarly journals Facial attractiveness and lip morphology of Caucasian women

2018 ◽  
Vol 81 (4) ◽  
pp. 404-413 ◽  
Author(s):  
Zdzisław Lewandowski ◽  
Dariusz P. Danel
Keyword(s):  
Empirical Study ◽  
Repeated Measures ◽  
Facial Attractiveness ◽  
Facial Features ◽  
Sexually Dimorphic ◽  
Men And Women ◽  
Repeated Measures Anova ◽  
Adult Men ◽  
Caucasian Women

Abstract Human lips are one of the most sexually dimorphic facial features. Although lip morphology is considered particularly important for female facial attractiveness no systematic empirical study has been conducted in this respect. This study aimed to investigate a relationship between female Caucasian facial attractiveness and their lip morphology. Two series of morphologically average composite portraits with digitally increased and decreased lip width and height measurements were assessed by adult men and women. Results were analysed using repeated measures ANOVA. When compared to the average lip shape both a decrease and an increase in lip width were associated with lower female facial attractiveness. A systematic increase in lip height from the lowest values to the highest, was associated with an increase in attractiveness scores. Attractiveness assessments of men and women did not differ significantly. The results show that perception of lip attractiveness may be intersexually congruent and that a variation in lip morphology may significantly affect female facial attractiveness.

Children’s Perceived Physical Competence at Different Categories of Physical Activity

1997 ◽  
Vol 9 (3) ◽  
pp. 237-242 ◽  
Author(s):  
Elaine Mullan ◽  
John Albinson ◽  
David Markland
Keyword(s):  
Physical Activity ◽  
Children And Adolescents ◽  
Repeated Measures ◽  
Perceived Competence ◽  
Competitive Sport ◽  
Physical Competence ◽  
Repeated Measures Anova ◽  
Recreational Activities ◽  
Athletic Competence ◽  
Competitive Activities

This study explored whether children differentiate between their physical capabilities at play activities, informal recreational activities, and formal competitive activities. Harter’s (11) six-item Athletic Competence subscale from the SelfPerception Profile for Children was administered to 578 children and adolescents (ages 7-15 years). The items were modified to refer to three different categories of physical activity instead of sport or outdoor games as used in the original subscale. Repeated measures ANOVA revealed that children differentiated between the three categories of physical activity, and that the competitive sport category was their area of lowest perceived competence. Males had higher levels of perceived competence than females in each category.

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