scholarly journals Abrasiveness of conventional and specific denture-cleansing dentifrices

2012 ◽  
Vol 23 (2) ◽  
pp. 154-159 ◽  
Author(s):  
Danilo Balero Sorgini ◽  
Claudia Helena da Silva-Lovato ◽  
Raphael Freitas de Souza ◽  
Letícia Resende Davi ◽  
Helena de Freitas Oliveira Paranhos
Keyword(s):  
Surface Roughness ◽  
Weight Loss ◽  
Mass Loss ◽  
Initial Period ◽  
Lower Surface ◽  
The Other ◽  
Distilled Water ◽  
Significance Level

This study analyzed the weight loss and surface roughness caused in Plexiglass specimens by conventional dentifrices (Sorriso, Colgate and Close Up) and specific dentifrices used for cleaning of dentures (Corega and Dentu Creme). Plexiglass specimens were divided into 6 groups (n=6) including: a control (distilled water - DW) and experimental groups. Brushing was performed in a toothbrushing machine with a soft brush and a dentifrice suspension and DW according to different brushing times (50, 100, 200 and 250 min -18,000, 36,000, 72,000 and 90,000 cycles, respectively, calculated to correspond to 1, 2, 4 and 5 years of regular brushing). The results of weight loss and surface roughness were analyzed by ANOVA and Tukey’s test at 5% significance level. In all tested times, the effect of DW was insignificant. Dentifrices differed significantly from DW in the initial period. Corega dentifrice caused greater mass loss in all studied times, followed by Close Up. Dentifrices resulted in a surface roughness similar to the DW at 50 min. In the other times, Sorriso, Colgate and Corega caused more surface roughness than DW. In conclusion, specific dentifrices caused larger mass loss and lower surface roughness as conventional dentifrice.

scholarly journals Evaluation of surface roughness and hardness of different glass ionomer cements

2012 ◽  
Vol 06 (01) ◽  
pp. 079-086 ◽  
Author(s):  
Oya Bala ◽  
Deniz Hacer Arisu ◽  
Ihsan Yikilgan ◽  
Seda Arslan ◽  
Abdulkadir Gullu
Keyword(s):  
Surface Roughness ◽  
Vickers Microhardness ◽  
Hardness Test ◽  
Lower Surface ◽  
The Other ◽  
Distilled Water ◽  
Glass Ionomer Cements ◽  
Measuring Instrument ◽  
Glass Ionomer ◽  
Hardness Values

ABSTRACTObjectives: The aim of this study was to evaluate surface roughness and hardness of a nanofiller GIC, a resin-modified GIC, three conventional GICs, and a silver-reinforced GICMethods: For each material, 11 specimens were prepared and then stored in distilled water at 37 °C for 24 h. The surface roughness of 5 specimens was measured using a surface profilometer before polishing and after polishing with coarse, medium, fine, superfine aluminum oxide abrasive Sof-Lex discs respectively. The hardness of the upper surfaces of the remaining 6 specimens was measured with a Vickers microhardness measuring instrument.Results: All tested GICs showed lower surface roughness values after the polishing procedure. Surface finish of nanofiller GIC was smoother than the other tested GICs after polishing. This was followed by resin-modified GIC, Fuji II LC; then silver-reinforced GIC, Argion Molar, conventional GICs, Aqua Ionofil Plus, Fuji IX, and Ionofil Molar, respectively. The result of the hardness test indicated that the microhardness value of silver-reinforced GIC was greater than that of the other GICs. When the hardness values of all tested GICs were compared, the differences between materials (except Aqua Ionofil Plus with Ionofil Molar and Ketac N100 with Fuji II LC (P>.05)) were found statistically significant (P<.05).Conclusions: According to the results of this study, it can be concluded that the differences in the composition of GICs may affect their surface roughness and hardness. (Eur J Dent 2012;6:79-86)

Effect of Ni and Zn Elements on the Microstructure and Antibacterial Properties of Cu Coatings

2019 ◽  
Vol 142 (1) ◽  
Author(s):  
Khaled S. Al-Athel ◽  
Najat Marraiki ◽  
Abul Fazal M. Arif ◽  
Syed Sohail Akhtar ◽  
Javad Mostaghimi ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Bacterial Adhesion ◽  
316L Stainless Steel ◽  
Coating Layer ◽  
Antibacterial Properties ◽  
Lower Surface ◽  
Distilled Water ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli

In this work, 316L stainless steel samples were coated with copper (Cu) and German silver (Cu 17%Ni 10%Zn) to investigate the relation between their mechanical and antibacterial behaviors. The mechanical and material characteristics of the samples were studied by looking into the microstructure of the surface and the cross-section of the coatings, the surface roughness, and the adhesion strength between the coating layer and the substrate. The antibacterial behavior is then studied against gram-negative Escherichia coli and gram-positive Staphylococcus aureus. Two experiments were conducted to examine the antibacterial behavior. In the first experiment, the coated samples were covered with distilled water, whereas in the second experiment, the samples were tested without being covered with distilled water. The results show that German silver (Cu 17%Ni 10%Zn) had a higher antibacterial rate than copper (Cu) by around 10% for both gram-negative E. coli and gram-positive S. aureus. The reason is because a smoother surface is expected to limit the bacterial adhesion in most cases, and the German silver samples have a lower surface roughness (Ra) due to the higher thermal expansion value of zinc (Zn) compared with copper (Cu). A more in-depth look into the effect of various thickness of the coating with alloying elements (in this case nickel and zinc) on the antibacterial rate would be of great interest.

scholarly journals In Vitro Evaluation of Physical and Mechanical Properties of Light-Curing Resin Cement: A Comparative Study

2020 ◽  
Vol 14 (01) ◽  
pp. 152-156
Author(s):  
Luís Felipe Espíndola-Castro ◽  
Oscar Felipe Fonseca de Brito ◽  
Larissa Gabrielle Assis Araújo ◽  
Izabella Luiza Aragão Santos ◽  
Gabriela Queiroz De Melo Monteiro
Keyword(s):  
Color Change ◽  
Surface Hardness ◽  
Color Stability ◽  
Resin Cement ◽  
The Other ◽  
Distilled Water ◽  
Water Control ◽  
Mean Values ◽  
Significance Level

Abstract Objective The aim of study was to evaluate in vitro the surface hardness, sorption, solubility, and color stability of three light-cured resin cements, namely RelyX Veneer (RLX), Variolink Veneer (VLK), and All Cem Veneer (ACV). Materials and Methods Cylindrical samples (15 × 1 mm) were made for each group using a metallic mold (n = 10). Vickers microhardness test was performed, and average hardness was calculated from three indentations (300 gf/15s) per sample. The sorption and solubility of the materials were evaluated according to ISO 4049:2009 based on three samples weighing: initial (m 1), after immersion in distilled water for 7 days (m 2), and final (after removal of all moisture [m 3]). The color change was observed using a digital spectrophotometer, at three different time points, baseline, 1 day, and 1 week of immersion in coffee and distilled water (control). Statistical Analysis Shapiro–Wilk test was used to analyze the normality of the data, and groups were compared using Kruskal–Wallis and Mann–Whitney tests. A significance level of 5% was used. Results RLX showed the highest microhardness mean values (36.96 VHN), but higher sorption (23.2 µg/mm3) and solubility (2.40 µg/mm3), with statistically significant differences with the other groups. For color stability, higher ∆E was observed for the samples immersed in coffee (p = 0.009). The VLK resin cement presented statistically significant differences from the other groups, with higher color changes in coffee at 1 day (15.14) and after 1 week (23.65). Conclusion RLX resin cement showed better hardness results. All materials tested performed satisfactorily for sorption and solubility according to ISO 4049:2009. All materials showed high-staining values after 1 week of immersion in coffee.

scholarly journals Avaliação de meios para armazenagem de resíduos de amálgama de prata

2021 ◽  
Vol 40 (2) ◽  
pp. 36-40
Author(s):  
Carmen Beatriz Borges Fortes ◽  
Susana Maria Werner Samuel
Keyword(s):  
Initial Period ◽  
The Other ◽  
Distilled Water ◽  
Air Samples ◽  
X Ray ◽  
Group 4 ◽  
Group I ◽  
Group 3 ◽  
Group 2 ◽  
Initial Storage

The purpose of this study was to evaluate the shown efectiveness by different ways of storage of amalgam residues, to reduce the liberation of mercury from such residues to the air ambience and to compare with lhe highest value established by the NR-15 (regulation norm number 15) from the decroe number 3214, of the brazilian labor ministry, dated from june, 8 h of 1978. As mercury source, amalgam in capsules of the brand Dispersalloy (Dentsplay) was used after grinding, in the mechanic amalgamizer varimix II (caulk), the quantity of amalgam in cach capsule was collected from a sieve that had a mesh with mm of width to standardize lhe fragmentation. The fragmented amalgam was stored in jars made of transparent polypropylene, that could store 5()() ml; one of the jars was kept in a dry atmosphere (group l), and the others were immersed in distilled water (group 2), in glycerin (group 3) and in a solution of dentistry x-ray fixer (group 4). These jars were kept tightly shut, and put inside a bigger polypropylene recipient, during the time they were stored. Thirty minutes after the storage of the fragments, the jars were opened and air samples were collected around each of the four jars. The same procedure was performed 30 days after the initial storage. A Pump Sampler of Air manufactured by SKCâ was used to do the air collection. The air samples were analyzed by a spectrophotorneter of atomic absorption, to determinate the quantity of mercury. This analysis showed the following mercury concentration rates in the air samples, from the first and the second collection of the four groups, in the following order: group I 6,100 mg/m3 and 0,816 mg/m3 ; group 2 - 0,252 mg/rn3 and 0,157 mg/m 3 ; group 3 — 0,071 mg/m3 and 0,005 mg/m3 ; groui) 4 — 0,256 mg/m3 and 0,005 mg/m3. The results showed that glycerin is the safest way to store amalgam residues, since the quantity of mercuor vapor found in the air, in both collections: the first one and the other 30 days after, never surpassed the highest value established by NR-15 (Regulation Norm number 15), also demonstrating, bigger security, since the initial period of storage of these residues.

scholarly journals Influence of Low-pH Beverages on the Two-Body Wear of CAD/CAM Monolithic Materials

Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2915
Author(s):  
Nicola Scotti ◽  
Andrei Ionescu ◽  
Allegra Comba ◽  
Andrea Baldi ◽  
Eugenio Brambilla ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Pairwise Comparison ◽  
Wear Test ◽  
In Vitro Study ◽  
The Other ◽  
Distilled Water ◽  
Volumetric Wear ◽  
Stainless Steel Ball ◽  
Cad Cam

The aim of this in vitro study is to evaluate the effect of different acidic media on volumetric wear and surface roughness of CAD/CAM monolithic materials. Forty-eight rectangular specimens were prepared using different CAD/CAM monolithic materials: nanohybrid composite (Grandio Blocks, Voco), resin-based composite (Cerasmart, GC), lithium disilicate (E-Max, Ivoclar), and high-translucency zirconia (Katana STML, Kuraray Noritake). After storage in distilled water at 37 °C for two days, the specimens were tested using a chewing machine with a stainless-steel ball as an antagonist (49N loads, 250,000 cycles). Testing was performed using distilled water, Coca-Cola, and Red Bull as abrasive media. Wear and surface roughness analyses of the CAD/CAM materials were performed using a 3D profilometer and analyzed with two-way analysis of variance and post hoc pairwise comparison procedures. Worn surfaces were examined using scanning electron microscopy. Resin-based materials suffered higher volumetric wear than ceramics (p = 0.00001). Water induced significantly less volumetric wear than the other tested solutions (p = 0.0014), independent of the material tested. High-translucency zirconia showed less surface roughness than all the other materials tested. The selection of monolithic CAD/CAM materials to restore worn dentition due to erosive processes could impact restorative therapy stability over time. Resin-based materials seem to be more influenced by the acidic environment when subjected to a two-body wear test.

scholarly journals Color Shift, Color Stability, and Post-Polishing Surface Roughness of Esthetic Resin Composites

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1376
Author(s):  
Yara Khalid Alkhadim ◽  
Malak Jameel Hulbah ◽  
Hani Mohammad Nassar
Keyword(s):  
Surface Roughness ◽  
Color Stability ◽  
Distilled Water ◽  
Significance Level ◽  
Color Changes ◽  
Significant Difference ◽  
Color Shift ◽  
Optical Profilometer ◽  
System Data ◽  
Multiple Comparison Methods

The aim of this study was to compare color shift, color stability, and post-polishing surface roughness of esthetic restorative materials. Twenty-five disc-shaped specimens (10 mm in diameter and 2 mm in thickness) from five esthetic resin materials (Z250XT, IPS Empress-Direct, G-ænial, Vit-l-escence, and Ceram.X) were fabricated. Color shift before and immediately after light-curing (∆E0) then color stability after immersion in tea, coffee, berry juice, and distilled water were measured using a spectrophotometer. Color changes were measured after 2 (ΔE2), 4 (ΔE4), 6 (ΔE6), and 8 weeks (ΔE8). Surface roughness values (Rq) were determined using an optical profilometer after polishing using a rotary polishing system. Data were analyzed using ANOVA and multiple comparison methods at 0.05 significance level. There were no significant differences between the tested materials regarding color shift except between Vit-l-escence and Ceram.X (p = 0.033). There was no significant difference between coffee and tea solutions (p = 1.0) and between berry juice and distilled water (p = 0.15). There was no difference between the tested materials regarding Rq (p = 0.057). Ceram.X was associated with the lowest ΔE8 values overall. Tested materials were comparable regarding color shift and post-polishing surface roughness. Susceptibility to staining was dependent on the material.

scholarly journals Long-term effects of seven cleaning methods on light transmittance, surface roughness, and flexural modulus of polyurethane retainer material

2018 ◽  
Vol 88 (3) ◽  
pp. 355-362 ◽  
Author(s):  
Manika Agarwal ◽  
Emily Wible ◽  
Tyler Ramir ◽  
Sibel Altun ◽  
Grace Viana ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Flexural Modulus ◽  
The Other ◽  
Light Transmittance ◽  
Qualitative Assessment ◽  
Long Term Effects ◽  
Significance Level ◽  
Cleaning Methods ◽  
Scanning Electron

ABSTRACT Objectives: To evaluate the long-term effects of seven different cleaning methods on light transmittance, surface roughness, and flexural modulus of a polyurethane retainer material. Materials and Methods: Polyurethane retainer specimens (Vivera®, Align Technology Inc) (70 specimens, n = 10 per method, 50.8 mm × 12.7 mm × 1.0 mm) were exposed to seven cleaning methods twice a week for 6 months. Before treatment and after 6 months, light transmittance, surface roughness, and flexural modulus of the specimens were quantified. Qualitative assessment of randomly selected specimens from each solution was performed at baseline and after 6 months using a scanning electron microscope. Statistical analyses were performed at the .05 significance level. Results: Of the three test variables, light transmittance through the specimens was the only one that changed significantly from baseline to 6 months for all cleaning solutions, with all of them causing a decrease. However, except for 0.6% sodium hypochlorite showing a change in surface roughness values and 2.5% vinegar and toothbrushing showing an increase in flexural modulus, none of the other four cleaning methods resulted in significant changes in surface roughness or flexural modulus values for the polyurethane specimens between baseline and after 6 months. Conclusions: Of the seven cleaning methods, Invisalign® cleaning crystals, Polident®, and Listerine® showed the least amount of change in light transmittance values for the polyurethane specimens over 6 months, and they had no effect on surface roughness and flexural modulus values.

scholarly journals Effectiveness of three solvents and two associations of solvents on gutta-percha and resilon

2011 ◽  
Vol 22 (1) ◽  
pp. 41-44 ◽  
Author(s):  
Norberto Batista de Faria-Júnior ◽  
Livia Etchebehere de Loiola ◽  
Juliane Maria Guerreiro-Tanomaru ◽  
Fábio Luis Camargo Villela Berbert ◽  
Mário Tanomaru-Filho
Keyword(s):  
Weight Loss ◽  
Initial Mass ◽  
Distilled Water ◽  
Orange Oil ◽  
Significance Level ◽  
Gutta Percha ◽  
Final Mass ◽  
The Mean ◽  
Capacity Data ◽  
Solvent Action

This study evaluated the effectiveness of 3 solvents (Citrol orange oil, Eucalyptol and Tetrachloroethylene) and 2 associations of solvents (Citrol orange oil+Tetrachloroethylene and Eucalyptol+Tetrachloroethylene) on 3 types of gutta-percha (conventional, thermoplastic and EndoREZ) and Resilon. Ten discs (10 mm diameter x 1 mm thick) from each material were prepared using standard metallic molds. Each specimen was weighed to determinate its initial mass. The specimens were immersed in the solvents for 10 min, followed by immersion in distilled water for 20 min, and were then reweighed to obtain the final mass. The mean weight loss determined the solvent capacity. Data were analyzed by ANOVA and Tukey's test at 5% significance level. Tetrachloroethylene was the most effective on conventional gutta-percha (p<0.05). Tetrachloroethylene was also the most effective on thermoplastic gutta-percha, but it was not significantly different (p>0.05) from Eucalyptol+Tetrachloroethylene, Citrol+Tetrachloroethylene, and Citrol. All solvents and associations presented little effectiveness on Resilon. The association Eucalyptol+Tetrachloroethylene was the most effective on EndoREZ, but it did not differ significantly (p>0.05) from Citrol+Tetrachloroethylene and Tetrachloroethylene. All evaluated substances presented solvent action. Tetrachloroethylene improved the effectiveness of both Citrol and Eucalyptol.

scholarly journals Do mouthwashes with and without bleaching agents degrade the force of elastomeric chains?

2013 ◽  
Vol 83 (4) ◽  
pp. 712-717 ◽  
Author(s):  
Matheus Melo Pithon ◽  
Ailana Cardoso Rodrigues ◽  
Érica Luiza Santana Moreira Sousa ◽  
Lília Paula de Souza Santos ◽  
Natália dos Santos Soares
Keyword(s):  
Artificial Saliva ◽  
Initial Period ◽  
Test Group ◽  
Experimental Period ◽  
The Other ◽  
Control Group ◽  
Distilled Water ◽  
Bleaching Agent ◽  
Time Intervals ◽  
Elastomeric Chains

ABSTRACT Objective: To evaluate, in vitro, the effect of mouthwashes with and without bleaching agents on the force of elastomeric chains. Materials and Methods: A total of 108 elastomeric chain specimens was divided into six groups (n  =  18 in each group). Two test groups were exposed to two types of commonly used mouthwashes (Plax and Listerine), and two groups were exposed to mouthwashes containing bleaching agent (Plax Whitening and Listerine Whitening). Immersion in the solutions was performed twice a day for 60 seconds. One group of control specimens remained immersed in artificial saliva throughout the entire experimental period, and the other control specimens were exposed to distilled water. Force measurements were performed at six time intervals (initial, 1 day, 7 days, 14 days, 21 days, and 28 days). Results: No statistically significant differences were found between the groups in the initial period (P &gt; .05). Statistically significant differences were found between the control group and the Plax, Plax Whitening, and Listerine groups at the time intervals of 7, 14, and 21 days. In the initial period, the force was statistically significantly higher than it was in any of the other experimental periods (P &lt; .05). The control group with distilled water and the test group with Plax Whitening maintained the most force during the experimental period. Conclusion: The presence of bleaching agent has no influence on the force degradation of elastomeric chains.

scholarly journals Evaluation of surface roughness and color change of a light-cured and a heat-cured acrylic resin employed for fabrication of prosthetic bases after exposure to different types of disinfectants

2013 ◽  
Vol 1 (3) ◽  
pp. 199
Author(s):  
Adriana Maria Jorge Dal'acqua Silva ◽  
Joice González Guerrero ◽  
Luciana De Rezende Pinto ◽  
Ricardo Martins Carvalho ◽  
Vinicius Carvalho Porto
Keyword(s):  
Surface Roughness ◽  
Sodium Hypochlorite ◽  
Composite Resin ◽  
Color Change ◽  
Acrylic Resin ◽  
Deionized Water ◽  
The Other ◽  
Distilled Water ◽  
Tukey Test ◽  
Different Types

This study evaluated the changes in surface roughness and color of materials employed in the fabrication of prosthetic bases after immersion in disinfectants. Sixty specimens were fabricated using a round matrix; half of the specimens were fabricated with a heat-cured composite resin, and the other half with a light-cured composite resin. After polishing, the specimens were stored in distilled water at 37ºC from 48 to 52 hours, and then submitted to initial tests of surface roughness and color. The specimens were randomly divided into three groups and immersed in the following chemicals: G1 (1% sodium hypochlorite for 10 minutes), G2 (5.25% sodium hypochlorite for 5 minutes) and G3 (2% acidic glutaraldehyde for 10 minutes). The surface roughness and color tests were once again performed and the specimens were then stored in deionized water at 37ºC for 6 days. On the seventh day, the immersion was repeated; this procedure was performed at every 7 days during 1 month and the tests were repeated after the fourth week. The results were submitted to three-way analysis of variance (ANOVA) and to the Tukey test. Within the same groups of specimens, statistically significant differences were only observed for the light-cured resin, which presented slight changes after exposure to 5.25% sodium hypochlorite and 2% glutaraldehyde for the interval ΔE2, which indicates differences in reading values between immersion after 30-day storage and the first immersion in the disinfectants.

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