scholarly journals Triazine Compound as Copolymerized Antibacterial Agent in Adhesive Resins

2017 ◽  
Vol 28 (2) ◽  
pp. 196-200 ◽  
Author(s):  
Priscila Raquel Schiroky ◽  
Vicente Castelo Branco Leitune ◽  
Isadora Martini Garcia ◽  
Fabrício Aulo Ogliari ◽  
Susana Maria Werner Samuel ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Triethylene Glycol ◽  
Knoop Hardness ◽  
Degree Of Conversion ◽  
Lower Percentage ◽  
Control Group ◽  
Glycol Dimethacrylate ◽  
Adhesive Resin ◽  
Kolmogorov Smirnov ◽  
Level Of Significance

Abstract The aim of this study was to formulate and evaluate an experimental adhesive resin with the addition of 1,3,5-triacryloylhexahydro-1,3,5-triazine at different concentrations. Experimental adhesive resins were obtained by mixing 50% wt bisphenol A glycol dimethacrylate (BisGMA), 25% wt triethylene glycol dimethacrylate (TEGDMA), 25% wt 2-hydroxyethyl methacrylate (HEMA) and photoinitiator system. The triazine compound was added in 1, 2.5 and 5% wt to a base adhesive resin and one group remained with no triazine as control group. The experimental adhesive resins were analyzed for antibacterial activity (n=3), degree of conversion (n=3) and softening in solvent (n=3). Data distribution was evaluated by Kolmogorov-Smirnov test, paired t test, one-way ANOVA and Tukey’s with a 0.05 level of significance. All groups with added triazine compound showed antibacterial activity against Streptococcus mutans (p<0.05). All groups achieved more than 70% degree of conversion, but there was no difference in this chemical property (p>0.05). The initial Knoop hardness was higher in 2.5 and 5% wt groups (p<0.05) and both groups present lower percentage variation of Knoop hardness after solvent degradation. The present study formulated an antibacterial adhesive resin with a non-releasing agent able to copolymerize with the comonomeric blend, improving the restorative material’s properties.

scholarly journals Effect of Adhesive Resin as a Modeling Liquid on Elution of Resin Composite Restorations

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Mohammadreza Maalekipour ◽  
Mehri Safari ◽  
Mehrdad Barekatain ◽  
Amirhossein Fathi
Keyword(s):  
Resin Composite ◽  
Triethylene Glycol ◽  
Control Group ◽  
Water Medium ◽  
Single Bond ◽  
Adhesive Resin ◽  
Triethylene Glycol Dimethacrylate ◽  
Composite Restorations ◽  
Methanol Medium ◽  
Urethane Dimethacrylate

Background. Adhesive resin is increasingly used as a modeling liquid for composite. Based on previous studies, elution of some components from the composite mass negatively affects the oral tissues. Since few studies have focused on the effect of adhesive resin on composite mass, this study aimed to investigate the effect of dental adhesion factors as modeling liquid on the elution of substances from composite restorations. Materials and Methods. Sixty-four composite specimens (6 × 2 mm diameter × height) were prepared in four groups (n = 16) by using a Teflon ring. Composite mass was incrementally applied in four layers (0.5 mm). The control group contained no material between the layers, but other groups had one of the single bond, SE bond, and wetting resin adhesives between the layers. Specimens were immersed in distilled water and methanol. The amount of released triethylene glycol dimethacrylate (TEGDMA), urethane dimethacrylate (UDMA), and camphorquinone (CQ) was monitored by gas chromatography after 24 hours and 7 days. Data were analyzed with SPSS software through Kruskal–Wallis and Mann–Whitney U tests (α = 0.05). Results. The highest rate of released TEGDMA comonomer was seen in the wetting resin group in the water medium. The highest rate of released UDMA monomer was seen in SE bond and wetting resin groups in the methanol medium after 24 hours. The highest amount of released CQ in the methanol medium was observed in the SE bond group after 7 days. Conclusion. Single bond adhesive can be used as modeling liquid since it has no significant effect on the elution of components from composite mass. Whereas, wetting resin and SE bond adhesives are not suitable to be used as modeling liquid due to the high amounts of released TEGDMA and UDMA.

Resin Penetration in Artificial Enamel Carious Lesions after Using Sodium Hypochlorite as a Deproteinization Agent

2014 ◽  
Vol 39 (1) ◽  
pp. 51-56 ◽  
Author(s):  
SS Gómez ◽  
P Bravo ◽  
R Morales ◽  
A Romero ◽  
A Oyarzún
Keyword(s):  
Sodium Hypochlorite ◽  
Polarized Light ◽  
Human Saliva ◽  
Conventional Technique ◽  
Surface Cleaning ◽  
Control Group ◽  
Adhesive Resin ◽  
Carious Lesions ◽  
Level Of Significance ◽  
And Control

Objectives: To study the degree of penetration of an adhesive resin in artificial enamel carious lesions after using sodium hypochlorite as deproteinization agent. Study design: Twenty included human third-molars, extracted for surgical indication, were used. Artificial lesions were created in the buccal and lingual sides of each specimen through a cycle of demineralization-remineralization. Samples were then incubated in human saliva for 7 days at 37 ° C. After surface cleaning, lesions and the peripheral sound enamel were etched with 37% orthophosphoric acid for 20 seconds. One lesion of each specimen was treated with 5.25% sodium hypochlorite (NaOCl) for one minute. The other lesion of each specimen was used as a control. Experimental and control lesions were sealed with a fluid resin marked with Rhodamine B. Lesions were sectioned for microscopic observation by epifluorescence and polarized light. The images obtained were analyzed morphometrically. The micrometer measurements were made with ImageJ ® software. The level of significance was assessed at p&lt;0.05. Results: The average sealant depth penetration in the control group was 94.9 ± 28.6 ?m versus 122.8 ± 25.3 μm in the experimental group. This represents Δ 20.1% significantly greater penetration when using sodium hypochlorite (p&lt;0.001). Conclusion: The results demonstrated a significant penetration of the sealing resin when the conventional technique is complemented with the application of 5.25% sodium hypochlorite for one minute in artificial enamel carious lesions.

In situ photopolymerization of dimethacrylamide-based resins and composites

2017 ◽  
Vol 52 (16) ◽  
pp. 2189-2197
Author(s):  
Yuling Xu ◽  
Juntao Zhang ◽  
Haibo Wang ◽  
Dong Xie
Keyword(s):  
Compressive Strength ◽  
Triethylene Glycol ◽  
Polymerization Rate ◽  
Degree Of Conversion ◽  
Glycol Dimethacrylate ◽  
Gel Time ◽  
Triethylene Glycol Dimethacrylate ◽  
Methacrylate Group ◽  
Ester Linkage

A dimethacrylamide was synthesized and used to formulate with the selected (meth)acrylates to form the in situ photocureable resins and composites. The effects of the selected comonomers with different functional groups on polymerization rate, degree of conversion, gel time, and compressive strength were investigated. The results show that in situ photopolymerization of the synthesized dimethacrylamide with comonomers having an electron-withdrawing and/or acrylate group dramatically increased the polymerization rate, degree of conversion, and compressive strength. On the other hand, an electron-donating group on either carbon-carbon double bond or ester linkage slowed down the polymerization. In contrast, the triethylene glycol dimethacrylate-based system did not show a clear pattern. The synergistic effect of the strong hydrogen-bonding between dimethacrylamide and organic acid groups may be responsible for higher compressive strengths. The formed composites showed the similar trend in compressive strength to the corresponding resins. Within the limitation of this study, it seems that in situ photopolymerization of dimethacrylamide or diacrylamide can be greatly accelerated by copolymerization with monomers having electron-withdrawing and/or acrylate groups. The monomers with methacrylate group can significantly reduce the polymerization rate and degree of conversion.

Antibacterial activity of self-adhesive resin cements against Streptococcus mutans at different time intervals

2019 ◽  
Author(s):  
Amir-Ahmad Ajami ◽  
Sahand Rikhtegaran ◽  
Mahmoud Bahari ◽  
Sayeh Hamadanchi
Keyword(s):  
Antibacterial Activity ◽  
Streptococcus Mutans ◽  
Study Groups ◽  
Control Group ◽  
Acidic Property ◽  
Resin Cements ◽  
Time Intervals ◽  
Adhesive Resin ◽  
The Mean ◽  
Phosphate Buffered Saline

Background and Objectives: Self-adhesive resin cements release fluoride and have cytotoxic and preventive monomers against the bacteria in their composition. They have acidic property before their complete setting too. The antibacterial ac- tivity of three different self-adhesive resin cements against Streptococcus mutans at different time intervals was investigated in this study. Materials and Methods: The modified direct contact test was used to evaluate the antibacterial effect of Max-Cem, G-Cem and Bis-Cem on S. mutans after aging the samples in phosphate-buffered saline solution for one hour, 24 hours and 1 week. Data were analyzed using one-way ANOVA, repeated measurement ANOVA and Tukey HSD tests (P<0.05). Results: The differences in the mean bacterial counts between all the study groups and between the study groups and the corresponding control groups were significant at 1-hour and 24-hour intervals (P<0.001). At 1-week, only the differenc- es between Bis-Cem and G-Cem, between Max-Cem and Bis-Cem, and between Bis-Cem and the corresponding control group were significant (P<0.001). There were significant differences between G-Cem and Max-Cem at all the time intervals (P<0.001). In addition, with the use of Bis-Cem there were significant differences between 1-hour and 1-week (P=0.01) and 24-hour and 1-week (P<0.001). Conclusion: All the cements exhibited antibacterial activity after 1 hour and 24 hours. However, after 1 week, only Bis-Cem retained its antibacterial activity.

Burnout of the Mind – Burnout of the Body?

2018 ◽  
Vol 32 (1) ◽  
pp. 30-42 ◽  
Author(s):  
Claudia Traunmüller ◽  
Kerstin Gaisbachgrabner ◽  
Helmut Karl Lackner ◽  
Andreas R. Schwerdtfeger
Keyword(s):  
Blood Pressure ◽  
Allostatic Load ◽  
Maslach Burnout Inventory ◽  
The Body ◽  
Lower Percentage ◽  
Control Group ◽  
Urinary Catecholamines ◽  
Morning Cortisol ◽  
The Mind ◽  
Cortisol Increase

Abstract. In the present paper we investigate whether patients with a clinical diagnosis of burnout show physiological signs of burden across multiple physiological systems referred to as allostatic load (AL). Measures of the sympathetic-adrenergic-medullary (SAM) axis and the hypothalamic-pituitary-adrenal (HPA) axis were assessed. We examined patients who had been diagnosed with burnout by their physicians (n = 32) and were also identified as burnout patients based on their score in the Maslach Burnout Inventory-General Survey (MBI-GS) and compared them with a nonclinical control group (n = 19) with regard to indicators of allostatic load (i.e., ambulatory ECG, nocturnal urinary catecholamines, salivary morning cortisol secretion, blood pressure, and waist-to-hip ratio [WHR]). Contrary to expectations, a higher AL index suggesting elevated load in several of the parameters of the HPA and SAM axes was found in the control group but not in the burnout group. The control group showed higher norepinephrine values, higher blood pressure, higher WHR, higher sympathovagal balance, and lower percentage of cortisol increase within the first hour after awakening as compared to the patient group. Burnout was not associated with AL. Results seem to indicate a discrepancy between self-reported burnout symptoms and psychobiological load.

TEACHING READING BY UTILIZING HOT POTATOES SOFTWARE TOWARD STUDENTS’ READING COMPREHENSION OF DESCRIPTIVE TEXT

2018 ◽  
Vol 5 (1) ◽  
pp. 26
Author(s):  
Abdullah Farih
Keyword(s):  
Reading Comprehension ◽  
Alternative Hypothesis ◽  
T Test ◽  
Control Group ◽  
Teaching Reading ◽  
Post Test ◽  
Quasi Experimental ◽  
Independent Variable ◽  
Level Of Significance ◽  
And Control

The objective of this study is to measure whether there is or not significant effect of teaching reading by utilizing Hot Potatoes software toward students’ reading comprehension of descriptive text. The variables used were the teaching treatment of Hot Potatoes Software as the independent variable and the students’ reading comprehension of Descriptive Text as dependent variable. Then, the research designed was Quasi-experimental design and the presentation of data used was quantitative. The data were obtained from the eleventh grade, of which 28 students were taken as sample. The students are divided into two groups; experiment group consisted of 12 students and control group consists of 16 students. To get the data, the pre-test and post-test were applied and then analyzed using t-test formula. The researcher had concluded that there is Significant effect of Hot Potatoes Software toward the students’ reading comprehension achievement. The result showed that mean of students’ post-test was increased. It is proved by the t-test (8.54) which is higher than t-table (2.05) at level of significance 5%. It means that the alternative hypothesis was accepted and it proved that Hot Potatoes Software had significant effect toward students’ reading comprehension of Descriptive Text

The Effect of Applying POSSE (Predict- Organize-Search-Summarize-Evaluate) on the Students’ Reading Comprehension

2013 ◽  
Vol 2 (1) ◽  
Author(s):  
Eka Rejeki Maha ◽  
Berlin Sibarani
Keyword(s):  
Reading Comprehension ◽  
Experimental Design ◽  
Null Hypothesis ◽  
Alternative Hypothesis ◽  
Choice Test ◽  
Control Group ◽  
Multiple Choice Test ◽  
Level Of Significance ◽  
And Control ◽  
Experimental Group

This study was aimed at finding out The Effect of Applying POSSE (Predict-Organize-Search-Summarize-Evaluate) Strategy on the Students’ Reading Comprehension. This study used the experimental design. The population of this study was the students of SMA Negeri 2 Medan. There were sixty students taken as the sample of the research. This study was conducted with two randomized groups namely experimental and control group. The experimental group was taught by applying POSSE strategy while control group was taught without applying POSSE strategy. The instrument of collecting the data was multiple choice test which consists of 40 items. To obtain the reliability of the test, the researcher used Kuder-Richardson (KR-21). The calculation shows the reliability was 0.81(high). The data were analyzed by using t-test. The calculation shows that t-observed (4.76) is higher than t-table (2.00) at the level of significance (α) 0.05 with the degree of freedom (df) 58. Therefore, the null hypothesis (Ho) is rejected and alternative hypothesis (Ha) is accepted. It means that there was a significant effect of applying POSSE strategy on the students’ reading comprehension. Keywords: POSSE Strategy, Reading Comprehension.

The Effect of Applying Learning Together Method on the Students’ Reading Comprehension

2012 ◽  
Vol 1 (2) ◽  
Author(s):  
Haryato Siregar ◽  
Elia Masa Ginting
Keyword(s):  
Reading Comprehension ◽  
Alternative Hypothesis ◽  
Choice Test ◽  
Control Group ◽  
Teaching Reading ◽  
Multiple Choice Test ◽  
Level Of Significance ◽  
And Control ◽  
Experimental Group ◽  
Learning Together

This study was aimed at finding out the effect of applying Learning Together Method on the students’ reading comprehension. This study used the experimental design. The population of this study was the students of SMP Negeri 1 Muara. There were sixty students of eighth class as the sample of the research. This study was conducted with two randomized groups namely experimental and control group. The experimental group was taught by applying Learning Together Method while control group was taught without applying Learning Together Method. The instrument of collecting the data was multiple choice test which consists of 20 items. To obtain the reliability of the test, the researcher used Kuder-Richardson (KR-21) formula. The calculation shows the reliability was 0.82(high). The data were analyzed by using t-test. The calculation shows that t-observed (4.9) is higher than t-table (2.00) at the level of significance (α) 0.05 with the degree of freedom (df) 58. Therefore, the null hypothesis (Ho) is rejected and alternative hypothesis (Ha) is accepted. It means that teaching reading comprehension by applying Learning Together Method significantly affect reading comprehension. Keywords: Learning Together Method, Reading Comprehension

THE EFFECT OF STORY MAPPING STRATEGY ON GRADE VIII STUDENTS’ ACHIEVEMENT IN WRITING NARRATIVE TEXT

2017 ◽  
Vol 6 (3) ◽  
Author(s):  
Aryadi Manuel Gultom And Isli Iriani Indiah Pane
Keyword(s):  
High School ◽  
Junior High School ◽  
Narrative Text ◽  
Control Group ◽  
Writing Test ◽  
Mapping Strategy ◽  
Story Mapping ◽  
Class Viii ◽  
Level Of Significance ◽  
Experimental Group

This research aims at investigating the effect of story mapping strategy on grade VIII students’ achievement in writing narrative text. It was conducted by using experimental research design. The Population of this research was the eighth (VIII) grade students of St. Thomas 1 Junior High School Medan. There were two classes as the sample. The first class (VIII-F) as the experimental group, while the second class (VIII-B) as the control group. The experimental group was taught by using story mapping strategy while control group was taught by using lecturing strategy. The instrument for collecting the data was writing test. The data were analyzed by using t-test formula. The analysis showed that the score of students in the experimental group by using story mapping strategy was higher than the score of students in the control group by using lecturing strategy, at the level of significance (α) 0.05 with the degree of freedom (df) 38, the t-observed was 2,818 while the t-table was 2,024. Therefore, the applying of story mapping strategy significantly affected the students’ achievement in writing narrative text.

THE EFFECT OF RAP (READ, ASK, PARAPHRASE) STRATEGY ON STUDENTS’ READING COMPREHENSION IN READING ANALYTICAL EXPOSITION TEXT

2015 ◽  
Vol 4 (3) ◽  
Author(s):  
Veronika N. And Lince Sihombing
Keyword(s):  
Reading Comprehension ◽  
Experimental Design ◽  
T Test ◽  
Control Group ◽  
Multiple Choice Tests ◽  
Choice Tests ◽  
Second Year ◽  
Level Of Significance ◽  
And Control ◽  
Experimental Group

This study focused on finding out the effect of applying RAP (Read, Ask,Paraphrase) Strategy on students’ reading comprehension in reading analyticalexposition text. This study was conducted in experimental design. The populationof this research was the second year of students in SMA Swasta Katolik BudiMurni 2 Medan. There were seventy students of the second year senior highschool students as the sample of the research. This study was conducted with tworandomized groups namely Experimental Group and Control Group. Theexperimental group was taught by applying RAP Strategy, while the control groupwas taught by applying conventional strategy. The instrument of collecting thedata was multiple choice tests which consisted of 25 items. The data wereanalyzed by using t-test formula. The calculation shown that t-observed (5.36)was higher than t-table (1.994) at the level of significance (α) 0.05 with the degreeof freedom (df) 68. It means that there was a significant effect of applying RAPStrategy on students’ reading comprehension in reading analytical exposition text.

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