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 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 Microhardness in pressing layers of prefabricated modified acrylic resin teeth

2014 ◽  
Vol 62 (2) ◽  
pp. 143-147
Author(s):  
Ricardo dos Santos BAPTISTA ◽  
Gustavo Duarte MENDES ◽  
Milton Edson MIRANDA ◽  
Cecilia Pedroso TURSSI
Keyword(s):  
Analysis Of Variance ◽  
Aluminium Oxide ◽  
Acrylic Resin ◽  
Superficial Layer ◽  
The Third ◽  
Molar Teeth ◽  
Artificial Teeth ◽  
Knoop Indenter

OBJECTIVE: The aim of this study was to evaluate the microhardness in pressing layers of prefabricated modified acrylic resin teeth. METHODS: Lower first molar teeth with two (Biotone(r) IPN and Bioform(r)) or three pressing layers (Artiplus(r), Trilux(r) Eurovipi, and Natusdent(r)) were hemisected in a bucco-lingual plane and embedded in a self-curing acrylic resin (n =10). Specimens were then ground flat and polished using 400, 600 and 1200 aluminium oxide paper in a rotatory polisher. In each pressing layer, microhardness was measured using a Knoop indenter in three different locations spaced 300 µm apart under a 10-g load, applied for 5 sec. RESULTS: Analysis of variance and Tukey's tests demonstrated that there was no difference in microhardness in the first layer of the teeth analyzed (p = 0.355), whereas in the second layer, the brand Artiplus(r) showed higher values when compared to the brand Natusdent(r) (p = 0.018). For the third layer, the brands Artiplus(r) and Trilux(r) Eurovipi revealed higher microhardness when compared to Natusdent(r) teeth (p < 0.001). CONCLUSION: For the outer most superficial layer of the artificial teeth, the microhardness of the different brands was similar, while differences were noted for the second and third layers among the artificial teeth, with Artiplus(r) teeth showing higher microhardness than Natusdent(r).

scholarly journals Chitosan: effect of a new chelating agent on the microhardness of root dentin

2012 ◽  
Vol 23 (3) ◽  
pp. 212-217 ◽  
Author(s):  
Josilaine Amaral Pimenta ◽  
Danilo Zaparolli ◽  
Jesus Djalma Pécora ◽  
Antonio Miranda Cruz-Filho
Keyword(s):  
Citric Acid ◽  
Chelating Agent ◽  
Acrylic Resin ◽  
Knoop Hardness ◽  
Distilled Water ◽  
Water Control ◽  
Three Solutions ◽  
All Solutions ◽  
Root Dentin ◽  
One Way Anova

The effect of solutions of 0.2% chitosan, 15% EDTA and 10% citric acid on the microhardness of root dentin was evaluated comparatively in this study. Thirteen sound human maxillary central incisors were selected and decoronated at the cementoenamel junction. Ten roots were set into rapid polymerization acrylic resin and the root/resin block was fitted to the cutting machine to obtain slices from the cervical third. The first slice was discarded and the second slice was divided into four quadrants. Each quadrant was used to construct a sample, so that 4 specimens were obtained from each root slice, being one for each chelating solution to be tested: 15% EDTA, 10% citric acid, 0.2% chitosan and distilled water (control). The specimens were exposed to 50 μL of the solution for 5 min, and then washed in distilled water. A microhardness tester (Knoop hardness) with a 10 g load was used for 15 s. Data were analyzed statistically by one-way ANOVA and Tukey-Kramer test (α=0.05). The other 3 roots had the canals instrumented and irrigated at the end of the biomechanical preparation with the test solutions, and then examined by scanning electron microscopy (SEM) for qualitative analysis. All solutions reduced the microhardness of root dentin in a way that was statistically similar to each other (p>0.05) but significantly different from the control (p>0.05). The SEM micrographs showed that the three solutions removed smear layer from the middle third of the root canal. In conclusion, 0.2% chitosan, 15% EDTA and 10% citric acid showed similar effects in reducing dentin microhardness.

scholarly journals Demineralization effect of EDTA, EGTA, CDTA and citric acid on root dentin: a comparative study

2005 ◽  
Vol 19 (3) ◽  
pp. 188-192 ◽  
Author(s):  
Simone Maria Galvão Sousa ◽  
Thelma Lopes Silva
Keyword(s):  
Citric Acid ◽  
Root Canal ◽  
Inductively Coupled Plasma ◽  
Saline Solution ◽  
Atomic Emission ◽  
Good Alternative ◽  
Emission Spectrometry ◽  
Plasma Atomic Emission Spectrometry ◽  
Inductively Coupled ◽  
Root Dentin

The purpose of this study was to biochemically compare the decalcifying effects of 1% EDTA (pH 7.4), 1% EGTA (pH 7.4), 1% CDTA (pH 7.4), 1% citric acid solutions (pH 1.0 and 7.4) and saline solution (control) on root dentin. Forty-eight single-rooted teeth were used in this study. The canals were instrumented by the step-back technique and the roots were randomly divided into six equal experimental groups (n = 8) according to the irrigating agent tested. A total of 30 µL of each solution was pipetted into the root canal and allowed to set undisturbed for 5 minutes. After this time, 15 µL of the solutions were removed from each canal using a Hamilton syringe and placed in a container with 5 mL of deionised water. The µg/mL concentration of calcium ion (Ca2+) extracted from the root canal samples was determined using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Data were analysed by means of the Kruskal-Wallis and Mood's median tests. Citric acid solution at pH 1.0 removed more calcium than at pH 7.4 and than the other chelating solutions tested (p < 0.05). No differences were observed between EDTA and EGTA. Both EDTA and EGTA removed significantly more calcium than CDTA and citric acid at pH 7.4 (p < 0.05). There were no differences between citric acid at pH 7.4 and saline solution, which had the least efficacy for Ca2+ extraction (p > 0.05). These results indicate that citric acid at pH 1.0 is a good alternative as an irrigating solution to remove the smear layer and facilitate the biomechanical procedures.

scholarly journals Comparison of physical and mechanical properties of microwave-polymerized acrylic resin after disinfection in sodium hypochlorite solutions

2009 ◽  
Vol 20 (4) ◽  
pp. 331-335 ◽  
Author(s):  
Helena de Freitas Oliveira Paranhos ◽  
Letícia Resende Davi ◽  
Amanda Peracini ◽  
Rafael Bellini Soares ◽  
Cláudia Helena da Silva Lovato ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Flexural Strength ◽  
Sodium Hypochlorite ◽  
Testing Machine ◽  
Physical And Mechanical Properties ◽  
Color Stability ◽  
Acrylic Resin ◽  
Bending Test ◽  
Water Control ◽  
Before And After

This study evaluated the color stability, surface roughness and flexural strength of a microwave-polymerized acrylic resin after immersion in sodium hypochlorite (NaOCl), simulating 20 min of disinfection daily during 180 days. Forty disk-shaped (15 x 4 mm) and 40 rectangular (65 x 10 x 3 mm) specimens were prepared with a microwave-polymerized acrylic resin (Onda-Cryl). Specimens were immersed in either 0.5% NaOCl, 1% NaOCl, Clorox/Calgon and distilled water (control). Color measurements were determined by a portable colorimeter. Three parallel lines, separated by 1.0 mm, were registered on each specimen before and after immersion procedures to analyze the surface roughness. The flexural strength was measured using a 3-point bending test in a universal testing machine with a 50 kgf load cell and a crosshead speed of 1 mm/min. Data were analyzed statistically by ANOVA and Tukey's test (?=0.05). There was no statistically significant differences (p>0.05) among the solutions for color, surface roughness and flexural strength. It may be concluded that immersion in NaOCl solutions simulating short-term daily use during 180 days did not influence the color stability, surface roughness and flexural strength of a microwave-polymerized acrylic resin.

scholarly journals Influence of the Chelating Solutions in the Resistance of Glass Fiber Posts to the Root Dentin

2020 ◽  
Vol 14 (04) ◽  
pp. 584-589
Author(s):  
Eduardo Fernandes Marques ◽  
Marília Fagury Videira Marceliano-Alves ◽  
Rina Andrea Pelegrine ◽  
Sérgio Luiz Pinheiro ◽  
Carlos Eduardo Da Silveira Bueno
Keyword(s):  
Citric Acid ◽  
Glass Fiber ◽  
Cross Sections ◽  
Saline Solution ◽  
Chelating Agent ◽  
Adhesive System ◽  
Fiber Glass ◽  
Fiber Posts ◽  
Glass Fiber Posts ◽  
Root Dentin

Abstract Objective This study aimed to evaluate the influence of chelating agents (EDTA, citric acid and Tetraclean) on glass fiber posts adhesion to root dentin. Materials and Methods Forty mandibular premolars single canals, with complete apical root, straight, circular cross sections were selected, accessed and had the cervical third prepared with Gates-Glidden drills, then included in resin, instrumented with ProTaper Universal and the root canal obturation was carried out. After, the samples were randomly divided into 4 groups (n = 10) to test the final irrigation solutions: G1:17% EDTA; G2:10% citric acid; G3: Tetraclean and G4: saline solution (control). After 30 days of storage (36.5° C and 100% humidity), the post preparation was performed leaving 4 mm of apical endodontic filling. Then, a fiber-glass post previously selected was coated with ED Primer adhesive system and resin sealer Panavia, installed and stored for 24 hours at 37°C. The samples were subjected to a tensile test with a constant speed of 1 mm/min with 2000 Kgf. The results were analyzed with the ANOVA test. Results The statistical analyzes indicated no significant differences between the groups (p > 0.05). Conclusion The type of chelating agent used in the final irrigation of the endodontic treatment did not influence the tensile strength of the fixation system used to sealer the glass fiber posts to the intracanal dentin.

scholarly journals Established an eco-friendly cotton fabric treating process with enhancing anti-wrinkle performance

2021 ◽  
Vol 16 ◽  
pp. 155892502110034
Author(s):  
Xiongfang Luo ◽  
Pei Cheng ◽  
Wencong Wang ◽  
Jiajia Fu ◽  
Weidong Gao
Keyword(s):  
Tensile Strength ◽  
Citric Acid ◽  
Cotton Fabric ◽  
Crosslinking Agent ◽  
Cost Effective ◽  
Waterborne Polyurethane ◽  
Cotton Fabrics ◽  
Wrinkle Resistance ◽  
Before And After ◽  
Strength Retention

This study establishes an eco-friendly anti-wrinkle treating process for cotton fabric. Sodium hydroxide-liquid ammonia pretreatment followed by 6% (w/w) PU100 adding citric acid pad-cure-dry finishing. In this process, citric acid (CA) was used as the fundamental crosslinking agent during finishing because it is a non-formaldehyde based, cost-effective and well wrinkle resistance agent. Environmental-friendly waterborne polyurethane (WPU) was used as an additive to add to the CA finishing solution. Six commercial WPUs were systematically investigated. Fabric properties like wrinkle resistance, tensile strength retention, whiteness, durable press, softness, and wettability were well investigated. Fourier transform infrared spectra and X-ray diffraction spectra were also measured and discussed before and after adding waterborne polyurethane. Tentative mechanism of the interaction among the WPU, CA, and modified cotton fabrics is provided. The effect of cotton fabric pretreatment on fabric performance was also investigated. After the eco-process’s treatment, the fabric wrinkle resistant angle was upgraded to 271 ± 7°, tensile strength retention was maintained at 66.77% ± 3.50% and CIE whiteness was elevated to 52.13 ± 3.21, which are much better than the traditional CA anti-wrinkle finishing based on mercerized cotton fabrics. This study provides useful information for textile researchers and engineers.

Microscopical analysis of Candida albicans biofilms on heat-polymerised acrylic resin after chlorhexidine gluconate and sodium hypochlorite treatments

Mycoses ◽  
2011 ◽  
Vol 54 (6) ◽  
pp. e712-e717 ◽  
Author(s):  
Paulo Maurício Batista da Silva ◽  
Emílio José T. Rodríguez Acosta ◽  
Luciana de Rezende Pinto ◽  
Márcia Graeff ◽  
Denise Madalena P. Spolidorio ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Sodium Hypochlorite ◽  
Acrylic Resin ◽  
Chlorhexidine Gluconate ◽  
Microscopical Analysis ◽  
Candida Albicans Biofilms

The Effect of Bleach Liquid and Household Cleaner on Surface Hardness and Roughness of Acrylic Base of Orthodontic Appliances

2021 ◽  
Author(s):  
Saeed Noorollahian ◽  
Farinaz Shirban ◽  
Vahid Mojiri
Keyword(s):  
Surface Roughness ◽  
Hydrochloric Acid ◽  
Sodium Hypochlorite ◽  
Surface Hardness ◽  
Acrylic Resin ◽  
Liquid Sodium ◽  
P Value ◽  
Orthodontic Appliances ◽  
Acrylic Resins ◽  
Significant Difference

Introduction: The daily use of orthodontic removable plates can interfere with the self-cleansing function of the mouth. Although various techniques have been proposed for cleaning removable orthodontic appliances, there is no consensus on the use of a safe method that preserves the physical properties of the appliance. This study aimed to investigate the effect of using hydrochloric acid (10%, for removal of mineral deposits) and sodium hypochlorite (5.25%, to remove organic matter and discolorations) on surface hardness and roughness of self-cure orthodontic acrylic resins. Materials & Methods: This cross-sectional laboratory study was conducted in the fall of 2017 at Isfahan University of Medical science and Isfahan University of Technology. In this study two orthodontic acrylic resins (Orthocryl® and Acropars®) were used. Eighty samples (12×10×3 mm) from each one were fabricated and divided into four groups (n = 20). Group 1: 15 minutes immersion in household cleaner liquid (Hydrochloric acid, 10%) followed by15 minutes immersion in household bleach liquid (Sodium Hypochlorite, 5.25%). In group 2, immersions were repeated just like group two times and in group 3, were done three times. Group 4 was as control and had no immersion. The surface hardness and roughness of samples were measured. Data were analyzed with Two Way ANOVA and the significance level was set at 0.05. Results: The number of immersion procedures did not significantly affect the surface hardness (p value = 0.958) and surface roughness (p value = 0.657) in the different study groups. There was no significant difference in the surface hardness between the two acrylic resin brands (p value = 0.077); however, Acropars acrylic resin samples exhibited significantly higher surface roughness compared to the Orthocryl acrylic resin samples(p value < 0.001). Conclusion: 15 minutes of immersion in 10% HCl, followed by 15 minutes of immersion in 5.25% NaOCl and repetition of the procedure three times did not significantly affect the surface hardness and roughness of self-cured acrylic resins.

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