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 Beta alanine supplementation effects on metabolic contribution and swimming performance

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Matheus Silva Norberto ◽  
Ricardo Augusto Barbieri ◽  
Danilo Rodrigues Bertucci ◽  
Ronaldo Bucken Gobbi ◽  
Eduardo Zapaterra Campos ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Energy Demand ◽  
Swimming Performance ◽  
Controlled Study ◽  
Double Blind ◽  
Repeated Measures Anova ◽  
Beta Alanine ◽  
Before And After ◽  
The Difference ◽  
And Performance

Abstract Background Investigations of β-alanine supplementation shows effects on metabolic (aerobic and anaerobic) participation and performance on swimming by a possible blood acidosis buffering. Considering this background, the objective of the present study was to analyze the effects of β-alanine supplementation on metabolic contribution and performance during 400-m swim. Methods Thirteen competitive swimmers underwent a 6-week, double-blind placebo-controlled study, ingesting 4.8 g.day− 1 of β-alanine or placebo. Before and after the supplementation period, the total anaerobic contribution (TAn) and 30-s all-out tethered swimming effort (30TS) were assessed. Anaerobic alactic (AnAl) and lactic energy (AnLa) was assumed as the fast component of excess post-exercise oxygen consumption and net blood lactate accumulation during exercise (∆[La−]), respectively. Aerobic contribution (Aer) was determined by the difference between total energy demand and TAn. In addition to conventional statistical analysis (Repeated measures ANOVA; p > 0.05), a Bayesian repeated measures ANOVA was used to evidence the effect probability (BFincl). Results No differences and effects were found between groups, indicating no supplementation effects. Repeated measures ANOVA, with confirmation of effect, was indicate reduce in ∆Lactate (p: 0.001; BFincl: 25.02); absolute AnLa (p: 0.002; BFincl: 12.61), fatigue index (p > 0.001; BFincl: 63.25) and total anaerobic participation (p: 0.008; BFincl: 4.89). Conclusions Thus, the results demonstrated that all changes presented were evidenced as a result of exposure to the training period and β-alanine supplementation doesn’t affect metabolic contribution and performance during 400-m freestyle.

scholarly journals Influence of Different Pigmentations and Accelerated Aging on the Hardness and Tear Strength of the A-2186 and MDX4-4210 Silicones

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Estefânia Marrega Malavazi ◽  
Daniela Micheline dos Santos ◽  
Clóvis Lamartine de Moraes Melo Neto ◽  
Fernanda Pereira de Caxias ◽  
Emily Vivianne Freitas da Silva ◽  
...  
Keyword(s):  
Analysis Of Variance ◽  
Repeated Measures ◽  
Accelerated Aging ◽  
Hardness Test ◽  
Strength Test ◽  
Tear Strength ◽  
Tukey Test ◽  
Repeated Measures Analysis ◽  
Before And After ◽  
Hardness Values

Objective. To evaluate the influence of different pigmentations and accelerated aging on the hardness and tear strength of the A-2186 and MDX4-4210 silicones. Materials and Methods. The samples A-2186 and MDX4-4210 were manufactured without and with pigmentations (black, bronze, and pink). For the Shore A hardness test, 80 samples of each silicone were fabricated, and for the tear strength test, 320 samples of each silicone were fabricated. Eight groups were created for each test (n = 10). These tests were performed before and after 252, 504, and 1008 hours of aging. Three-way repeated-measures analysis of variance and the Tukey test were performed (α = 0.05). Results. The A-2186 silicone showed higher hardness and tear strength when compared with the MDX4-4210 silicone p<0.05, except in the hardness of the A-2186 and MDX4-4210 groups without pigmentation after 1008 hours p>0.05. All hardness values were between 25 and 35 units, regardless of the silicone type, period, and pigmentation (or no pigmentation). In most situations, the hardness of silicones used increased after 252 hours p<0.05. The nonpigmented MDX4-4210 group and all A-2186 groups showed an increase in tear strength after 252 hours p<0.05. For the nonpigmented MDX4-4210 group, from 252 to 1008 hours, there was no change in tear strength p>0.05. All pigmented MDX4-4210 groups showed no change in tear strength from 0 (initial) to 1008 hours of aging p>0.05. In all A-2186 groups, from 252 to 504 hours, there was a reduction in tear strength p<0.05, and from 504 to 1008 hours, there was an increase in tear strength p<0.05, except in the bronze A-2186 group p>0.05. Conclusion. In most situations, the A-2186 silicone showed significantly higher values of hardness and tear strength than the MDX4-4210 silicone. All hardness values were considered clinically acceptable. Accelerated aging could increase, decrease, or not significantly change the hardness and tear strength of the silicones used. The results of hardness and tear strength suggest that MDX4-4210 was more influenced by the presence of pigmentation after aging.

Comparative Analysis of Root Dentin Morphology and Structure of Human Versus Bovine Primary Teeth

2015 ◽  
Vol 21 (3) ◽  
pp. 689-694 ◽  
Author(s):  
Bruna M. Costa ◽  
Alexsandra S. Iwamoto ◽  
Regina M. Puppin-Rontani ◽  
Fernanda M. Pascon
Keyword(s):  
Repeated Measures ◽  
Primary Teeth ◽  
Primary Root ◽  
Repeated Measures Anova ◽  
Root Canals ◽  
Morphology And Structure ◽  
Root Dentin ◽  
Dentin Tubules ◽  
Morphological Differences ◽  
Scanning Electron

AbstractThis study evaluated the structural and morphological differences between human and bovine primary root canals. Primary human maxillary central incisors (H) (n=9) and primary bovine incisors (B) (n=9) were selected. The roots were sectioned in the vestibular-lingual direction, planed and delimited in cervical, middle, and apical thirds. Tubule density (number of tubules per mm2) and diameter were analyzed by scanning electron microscopy (1,000 and 5,000×) using Image J 1.47 software. Data were submitted to two-way repeated measures ANOVA and Tukey tests (α=0.05). The highest tubule density was observed for B (28.527±1.717 mm2) compared with H (15.931±0.170 mm2) (p<0.01). Regarding root thirds, the cervical third presented a greater tubule density (26.417±11.654 mm2) than the apical third (17.999±5.873 mm2). The diameter of the dentin tubules was not different for cervical (3.50±0.08 µm), middle (3.45±0.30 µm) and apical thirds (3.42±0.33 µm) and substrate (H—3.29±0.14 µm; B—3.63±0.06 µm). It could be concluded that: (1) the radicular dentin structure of human and bovine primary teeth and root thirds differ in terms of the tubule density; (2) the radicular dentin morphology of human and bovine primary teeth and root thirds are similar in terms of the diameter of the dentin tubules.

scholarly journals The Effect of Ultrasonic Agitation on the Porosity Distribution in Apically Perforated Root Canals Filled with Different Bioceramic Materials and Techniques: A Micro-CT Assessment

2021 ◽  
Vol 10 (21) ◽  
pp. 4977
Author(s):  
Saulius Drukteinis ◽  
Goda Bilvinaite ◽  
Hagay Shemesh ◽  
Paulius Tusas ◽  
Vytaute Peciuliene
Keyword(s):  
Root Canal ◽  
Micro Computed Tomography ◽  
Root Canal Filling ◽  
Porosity Distribution ◽  
Significance Level ◽  
Ultrasonic Agitation ◽  
Root Canals ◽  
Gutta Percha ◽  
Before And After ◽  
Rotary Instrument

The present study evaluated the effect of ultrasonic agitation on the porosity distribution of BioRoot RCS/single gutta-percha cone (BR/SC) and MTA Flow (MF) root canals fillings used as apical plugs in moderately curved and apically perforated roots. Eighty mesial root canals of mandibular first molars were enlarged up to ProTaper NEXT X5 rotary instrument 2 mm beyond the apical foramen, simulating apical perforations. Specimens were randomly divided into four experimental groups (20 canals per group) according to the material and technique used for root canal obturation: BR/SC, BR/SC with ultrasonic agitation (BR/SC-UA), MF and MF with ultrasonic agitation (MF-UA). The ultrasonic tip was passively inserted into the root canal after the injection of flowable cement and activated for 10 s. The specimens were scanned before and after obturation with a high-resolution micro-computed tomography scanner, and the porosity of the apical plugs was assessed. The differences between groups were analyzed using the Kruskal-Wallis and Mann-Whitney tests, with the significance level set at 5%. None of the obturation materials and techniques used in this study was able to provide a pore-free root canal filling in the apical 5 mm. Considerably higher percentages of open and closed pores were observed in the MF and MF-UA groups, with the highest porosity being in the MF-UA group (p < 0.05). No significant differences were observed between the BR/SC and BR/SC-UA groups, where the quantity of open and closed pores remained similar (p > 0.05).

The effect of serrating abutment-implant mating surface on torque stability of implant-abutment connection, before and after cyclic loading.

2020 ◽  
Author(s):  
Vida Rezayani ◽  
Marzieh Alikhasi ◽  
Abbas Monzavi
Keyword(s):  
Cyclic Loading ◽  
Repeated Measures ◽  
Peak Load ◽  
T Test ◽  
The Other ◽  
Repeated Measures Anova ◽  
Implant Abutment ◽  
Before And After ◽  
Torque Loss ◽  
Connection Design

This study evaluated the effect of adding serration to the abutment-implant connection on torque maintenance before and after loading. Two implant systems with the same dimensions and connection design (internal 8˚morse taper octagon) were selected: one with non-serrated abutments (Simple line II) and the other one with serrated abutments (F & B). The removal torque value (RTV) was measured in two groups for each system: one group with one-piece abutments and the other group with two-piece abutments, before and after cyclic loading (n=10 in each group). The initial RTV of the abutment screw was measured with a digital torque meter. Each abutment received a cement-retained metal crown with 30° occlusal surface. Cyclic axial peak load of 75±5 N was applied to the implants for 500,000 cycles at 1 Hz. The post-load RTV was then measured. Two-way and repeated measures ANOVA, and independent t-test were applied to assess the effects of cyclic loading, connection design, abutment type, and their interaction on the percentage of torque loss (α=.05). Two-way ANOVA showed that serration of mating surfaces had a significant effect on torque maintenance before (P&lt;0.001) and after (P=0.004) cyclic loading. Repeated measures ANOVA also showed that loading had a significant effect on the torque loss percentage (P&lt; 0.01). Comparison of the groups with t-test showed that the torque loss of the serrated groups was lower than that of non- serrated groups. Despite the limitations of this study, the stability of the implant-abutment connection in the serrated design was higher than that of non-serrated group.

scholarly journals A New Weak Chelator in Endodontics: Effects of Different Irrigation Regimens with Etidronate on Root Dentin Microhardness

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Talita Tartari ◽  
Patrícia de Almeida Rodrigues Silva e Souza ◽  
Bruno Vila Nova de Almeida ◽  
José Otávio Carrera Silva Júnior ◽  
Oscar Facíola Pessoa ◽  
...  
Keyword(s):  
Citric Acid ◽  
Analysis Of Variance ◽  
Sodium Hypochlorite ◽  
Saline Solution ◽  
Acrylic Resin ◽  
Before And After ◽  
Root Dentin ◽  
Knoop Indenter

This study investigated the effect of sodium hypochlorite (NaOCl), ethylenediaminetetraacetic (EDTA), etidronic (HEBP), and citric acid (CA) associated in different irrigation regimens on root dentin microhardness. Forty-five root halves of single-rooted teeth were sectioned into thirds that were embedded in acrylic resin, polished, randomly assigned into 3 groups, and treated as follows: G1: saline solution; G2: 5% NaOCl + 18% HEBP, mixed in equal parts; and G3: 2.5% NaOCl. After measurements, the G3 samples were distributed into subgroups G4, G5, and G6, which were submitted to 17% EDTA, 10% CA and 9% HEBP, respectively. Following the new measurements, these groups received a final flush with 2.5% NaOCl, producing G7, G8, and G9. Microhardness was measured with Knoop indenter under a 25 g load for 15 seconds, before and after treatments. The data were statistically analyzed using paired Student’st-test (α<0.05) to compare values before and after treatments and analysis of variance (ANOVA) (α<0.05) to detect any differences among thirds. Except G1, all tested irrigation regimens significantly decreased the microhardness. There were no differences between root thirds before treatments, and all root thirds exhibited equal responses to same treatment. Except saline, all tested irrigation regimens reduced the root dentin microhardness.

scholarly journals Behavioural and physiological responses of West African Dwarf Goat dams and kids subjected to short-term separation

2018 ◽  
Vol 51 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Oluwaseun Serah Iyasere ◽  
Ikechuckwu Joseph James ◽  
Tolulope Julius Williams ◽  
James Olamitubo Daramola ◽  
Kabir Olumide Lawal ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Physiological Responses ◽  
West African ◽  
Short Term ◽  
Repeated Measures Anova ◽  
Physiological Indicators ◽  
West African Dwarf ◽  
West African Dwarf Goat ◽  
Before And After ◽  
Eye Temperature

Abstract Nineteen West African Dwarf (WAD) goats were used to investigate the physiological and behavioural responses of dams and kids to short-term separation. The dams were naturally mated with bucks and after parturition the kids remained with their respective dams for 5 weeks. Thereafter, the dams were separated from their kids for 10 minutes / week for three weeks (week 5 – 7). Physiological indicators, namely, eye temperature (ET), heart rate (HRT) and blood glucose (GLUC) were taken from each dam, while the ET and HRT were taken from the kids before and after the separation. The behaviours of the dams and kids were recorded during the separation period at the 7th week. Changes (before minus after) in the physiological parameters (ET, HRT and GLU) for the three weeks were analysed using repeated measures ANOVA while the behavioural data were analysed using non parametric test (SPSS statistical package). The ΔGLUC of WAD dams was greater at the 5th than 7th week. At the 5th week also, the ΔET was greater in dams with single kids than those with twins. Litter size did not influence the behaviour of the dams during separation. A significant correlation was established between ΔHRT and urination in dams. Although sex of the kids had no significant effect on both the physiological and behavioural indicators monitored, negative correlations were established between vocalization bouts and escape attempts (r = −0.516, P < 0.01), duration of vocalisation and escape attempts (r = −0.427, P < 0.05). In conclusion, only WAD dams showed physiological responses indicative of stress during the period of separation.

scholarly journals Comparative analysis of the surface roughness of conventional resins and filling after immersion in mouthwashes

2020 ◽  
Vol 19 ◽  
pp. e208569
Author(s):  
Juliana de Souza Silva Zica ◽  
Isabela Araújo Fernandes ◽  
Fernanda Barcellos Ameno Faria ◽  
Fernanda Cruz Ferreira ◽  
Nívea Aparecida Reis Albuquerque ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Comparative Analysis ◽  
Statistical Analysis ◽  
Repeated Measures ◽  
Composite Resin ◽  
Composite Resins ◽  
Repeated Measures Anova ◽  
Before And After

Aim: Bulk Fill composite resins were released on the market in order to reduce the time in clinical sessions by using increments of up to 5.0 mm thickness. The aim of this study was to evaluate the effect of the rinsing solutions on the surface roughness of the conventional composite and Bulk fill composite resins. Methods: 40 specimens were prepared from a 4.0mm x 10.0mm teflon matrix and photoactivated for 20 seconds, with 20 specimens made of Filtek Bulk-Fill composite resin (3M ESPE) and 20 specimens made with Filtek™ Z350 XT composite resin (3M ESPE). Each group was subdivided into 2 subgroups: G1 (Filtek™ Z350 XT-3M ESPE-immersed in Colgate PlaxWhitening®); G2 (Filtek™ Z350 XT-3M ESPE-immersed in PlaxFreshMint®); G3 (Filtek™ Bulk-Fill-3M ESPE-immersed in Colgate PlaxWhitening®) and G4 (Filtek™ Bulk-Fill-3M ESPE-immersed in Colgate PlaxFreshMint®). The surface roughness test was performed initially and after immersion in rinses by the Time Group Inc.-TR200® rugosimeter apparatus and the data were submitted to statistical analysis (two-way repeated measures ANOVA). Results: Surface roughness values of the Filtek™ Bulk-Fill composite resin (3M ESPE) were significantly higher than the Filtek™ Z350 XT composite resin (3M ESPE) (P <0.0001). However, no differences were identified before and after immersion in rinses with or without alcohol. Conclusion: The use of mouthwashes does not interfere with the surface roughness of the tested resins, but the composite resin Filtek Z350 XT (3M ESPE) presents a surface with less roughness.

Kinesio Taping and Jump Performance in Elite Female Track and Field Athletes

2015 ◽  
Vol 24 (1) ◽  
pp. 47-50 ◽  
Author(s):  
Thorsten Schiffer ◽  
Anne Möllinger ◽  
Billy Sperlich ◽  
Daniel Memmert
Keyword(s):  
Repeated Measures ◽  
Rectus Femoris ◽  
Track And Field ◽  
Kinesio Tape ◽  
Jump Performance ◽  
Repeated Measures Anova ◽  
Jumping Performance ◽  
Jump Test ◽  
Before And After ◽  
Improve Muscle Strength

Context:The application of kinesio tape (KT) to lower-extremity muscles as an ergogenic aid to improve muscle-strength-related parameters such as jumping is controversial.Objective:To test the hypothesis that the application of KT enhances the jumping performance of healthy uninjured elite female track and field athletes.Design:A double 1-legged jump test was performed before and after the application of blue K-Active tape without traction on the maximally stretched gastrocnemius, hamstrings, rectus femoris, and iliopsoas muscles according to the generally accepted technique.Participants:18 German elite female track and field athletes (age 21 ± 2 y, height 172 ± 4 cm, body mass 62 ± 5 kg, active time in their sport 13 ± 4 y).Results:Factorial analysis of variance with repeated measures (ANOVA, Bonferroni) revealed no significant differences in jumping performance between the tests (P > .05, d = 0.26).Conclusions:These findings suggest that the application of KT has no influence on jumping performance in healthy, uninjured female elite athletes. The authors do not recommend the use of KT for the purpose of improving jump performance.

scholarly journals Sense of Coherence, Health, Well-Being, and Work Satisfaction before and after Implementing Activity-Based Workplaces

2020 ◽  
Vol 17 (14) ◽  
pp. 5250
Author(s):  
Katarina Wijk ◽  
Eva L. Bergsten ◽  
David M. Hallman
Keyword(s):  
Sense Of Coherence ◽  
Repeated Measures ◽  
Work Satisfaction ◽  
Well Being ◽  
Psychosocial Work Environment ◽  
Psychosocial Work ◽  
Focus Group Interviews ◽  
Repeated Measures Anova ◽  
Before And After ◽  
Group Interviews

Activity-based workplaces (ABWs) are implemented with possible implications for health, well-being, and work satisfaction in the workplace. Drawing on the theoretical framework, i.e., sense of coherence (SOC), the aim was to investigate how indicators pf SOC—meaningfulness, manageability and comprehensibility—are associated with, or function as barriers or facilitators for, health, well-being and work satisfaction during relocation to an ABW. We followed the implementation of ABWs at the Swedish Transport Administration (2018–2019). Questionnaires were administered before (n = 536), 3 months (n = 409) and 9 months (n = 373) after relocation. Focus group interviews (15) were conducted before and after. Data were analyzed using repeated measures ANOVA and content analysis. Relocation to an ABW was associated with a reduced work satisfaction (physical p < 0.001; psychosocial p < 0.001), and minor changes in health and occupational well-being during relocation (p > 0.001). The reduction in work satisfaction was smaller among employees with high meaningfulness in the relocation process (p < 0.001). All SOC indicators were positively associated with overall health, well-being and work satisfaction (p < 0.001). Interviews suggested that meaningfulness was facilitated by participation in the presented activities and that communication before relocation was crucial. The results indicate that organizations implementing ABWs should promote perceived meaningfulness in the process to mitigate possible declines in satisfaction with the physical and psychosocial work environment.

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