scholarly journals Effect of Fluoride Gels on Microhardness and Surface Roughness of Bleached Enamel

2014 ◽  
Vol 8 (1) ◽  
pp. 188-193 ◽  
Author(s):  
Ana L.P China ◽  
Nayara M Souza ◽  
Yasmin do S. B. de L Gomes ◽  
Larissa D Alexandrino ◽  
Cecy M Silva
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Tooth Enamel ◽  
Distilled Water ◽  
Bleaching Agent ◽  
Fluoride Treatment ◽  
Before And After ◽  
Knoop Microhardness ◽  
Roughness Measurements

The effect of bleaching treatments containing added calcium and combined with neutral or acidic fluoride gels on tooth enamel was investigated in vitro through Knoop microhardness (KHN) and surface roughness (SR) measurements. A total of 60 bovine incisors were tested, including 30 for SR measurements and 30 for KHN measurements. The specimens were divided into 12 groups and subjected to a bleaching agent with hydrogen peroxide 35% (Whiteness HP 35% Maxx, FGM) or hydrogen peroxide 35% with calcium (Whiteness HP 35% Blue Calcium, FGM) and a fluoride treatment flugel acidulated phosphate fluoride (APF) or flugel neutral fluoride (NF). Control specimens were submitted to bleaching treatments without fluoride. Microhardness tests were performed using a Knoop indentor. Roughness measurements were obtained using a roughness analyzer. Measurements were obtained before and after treatment. The specimens were stored in distilled water at 37 °C between treatments. The results were analyzed using descriptive and inferential statistics. Treatments using APF combined with 35% HP caused a decrease in microhardness, while NF combined with HP 35% Ca increased the enamel hardness. Fluoride gels did not alter the SR of the bleached enamel.

scholarly journals Preliminary In Vitro Wear Assessment of Ceramic Cemented Femoral Components Coupled with Polyethylene Menisci

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2112
Author(s):  
Saverio Affatato ◽  
Paolo Erani ◽  
Maurizio Fersini ◽  
Vincenzo Contaldi ◽  
Anna Rita Terrizzi ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Wear Resistance ◽  
Monoclinic Phase ◽  
Calf Serum ◽  
Wear Test ◽  
Clinical Test ◽  
Preliminary Evaluation ◽  
Before And After ◽  
Roughness Measurements

Success of total knee replacement (TKR) depends on the prosthetic design and materials. The use of metal components is well established with the disadvantage of allergic reactions. Ceramics have been recently proposed because of high wear resistance, excellent biocompatibility, wettability, and suitable mechanical properties. This study was aimed at investigating in vitro wear resistance of Zirconia Toughened Alumina (ZTA)/Ultra-high-molecular-weight polyethylene (UHMWPE) of TKR femoral components. An in vitro protocol was designed with the application of relevant load profile, 6-degrees-of-freedom knee simulator, and 8 × 105 cycles on the ZTA/UHMWPE configuration under bovine calf serum. Before and after wear test, the femoral components were investigated by using the Scanning Electron Microscope (SEM) and the X-Ray Diffraction (XRD) analyses, and stylus surface roughness measurements. The proposed pre-clinical test yielded repeatable results. In particular, gravimetric results showed that, after 8 × 105 cycles, the mean weight loss of the polyethylene mobile components is 5.3 ± 1.1 mg. The surface roughness measurements (Ramax) performed after the wear test showed no significant variation on the UHMWPE menisci. A slight increase of roughness has been found on the ZTA (0.02 µm before wear test, 0.28 µm after the test). SEM observations did not show significant modification of the surface morphology. Tetragonal to monoclinic phase ratio was measured by XRD before and after wear test to evaluate stability of tetragonal ZrO2 phase. Minimal conversion of tetragonal to monoclinic phase was found from 5.4 to 8%. Although this study is a preliminary evaluation limited to in vitro tests, it provides novel pre-clinical indications about the potential of ceramic TKR femoral components.

scholarly journals Effect of In-Office Bleaching on Color and Surface Roughness of Composite Restoratives

2010 ◽  
Vol 04 (02) ◽  
pp. 118-127 ◽  
Author(s):  
Randa Hafez ◽  
Doa Ahmed ◽  
Mai Yousry ◽  
Wafa El-Badrawy ◽  
Omar El-Mowafy
Keyword(s):  
Surface Roughness ◽  
Surface Texture ◽  
Color Change ◽  
Distilled Water ◽  
Bleaching Agent ◽  
Color Changes ◽  
Before And After ◽  
Colorimetric Measurements ◽  
Natural Teeth ◽  
Environmental Sem

Objectives: The purpose of this study was to determine color changes and surface roughness of composites when they were subjected to in-office bleaching.Methods: 12 discs 15 mm in diameter and 2 mm thick were prepared from two shades (A2 & A4) of two composites, Durafil VS (DF) and TPH3 (TPH). Specimens were polished and stored in distilled water for 24 hours at 37°C before being subjected to bleaching, staining, and re-bleaching. Each of the groups of specimens (DF-A2, DF-A4, TPH-A2 and TPH-A4) were subdivided into three subgroups (n=4) and bleached with Beyond, LumaWhite-Plus, and Opalescence-Boost. Specimens were then stained by immersing them in a coffee solution for 48 hours at 37°C, and then they were re-bleached. Colorimetric measurements were performed at baseline, after bleaching, after staining, and after rebleaching. Surface roughness was determined with environmental SEM before and after bleaching. Data were statistically-analyzed.Results: None of the bleaching systems notably changed the color of composites (delta-E<2). Coffee staining affected DF specimens more than TPH. Stained specimens showed variable responses to whitening with no significant color change observed with TPH (delta-E<2) and significant changes observed with DF. Surface roughness significantly changed with bleaching, but the degree varied according to composite shade and bleaching agent.Conclusions: Three in-office bleaching agents had no significant color changes on two composites. DF showed more color change than TPH when immersed in coffee. Stained composites showed different degrees of whitening, with DF showing more response. Bleaching may adversely affect the surface texture of composites. Dentists should take into consideration that composite restorations may not respond to bleaching in the same way that natural teeth do. (Eur J Dent 2010;4:118-127)

scholarly journals The effect of a bleaching agent on the pigment removal and the bond strength of bulk-fill resin composites: an in vitro study

2018 ◽  
Vol 47 (5) ◽  
pp. 298-304
Author(s):  
Caroline de Farias CHARAMBA ◽  
Renally Bezerra Wanderley LIMA ◽  
Sônia Saeger MEIRELES ◽  
Rosângela Marques DUARTE ◽  
Ana Karina Maciel ANDRADE
Keyword(s):  
Bond Strength ◽  
Color Change ◽  
Resin Composite ◽  
Distilled Water ◽  
Filling Material ◽  
Resin Composites ◽  
Bleaching Agent ◽  
Microtensile Testing ◽  
Before And After

Abstract Introduction In order to simplify the technique, reduce the time required for direct adhesive restorations, bulk-fill resin composites have been developed be applied in bulk placement up to 4 mm increments. Objective Evaluating the color change (ΔE) and the microtensile bond strength (μTBS) of bulk fill resin composites (BFRC) to dentin after the immersion in regular beverages and the application of bleaching systems. Method Forty-five human molar teeth were randomly distributed in three groups according to the filling material (n=15): Filtek Bulk Fill, Tetric N Ceram Bulk Fill and Filtek Z100. The restored teeth were immersed in coffee, wine and distilled water (n=5) for 72 hours. The color parameters were measured using a spectrophotometer, having as basis the CIE L*a*b*, before and after tooth staining and application of bleaching processes. Subsequently, the teeth were sectioned to obtain the specimens for the microtensile testing. The ΔE values were analyzed applying the Kruskal-Wallis and the Wilcoxon tests, and the μTBS values were analyzed applying the ANOVA and the Bonferroni tests (p<0.05). Result There were no significant differences in the ∆E values when comparing the BFRCs to the conventional resin composite (CRC) in most of the experimental groups. The ∆E values did not present significant differences before and after the application of bleaching processes for all the tested resin composites. The BFRCs presented higher μTBS values than the CRC after exposure to distilled water, wine and bleaching agent. Conclusion The studied BFRCs presented similar color stability to the CRC. The BFRCs presented higher bond strength to the dentin than the CTC in most of the evaluated conditions. The bleaching agent was not effective in whitening the stained restored teeth.

The Effect of Copper on Demineralization of Dental Enamel

2006 ◽  
Vol 85 (11) ◽  
pp. 1011-1015 ◽  
Author(s):  
A.Z. Abdullah ◽  
S.M. Strafford ◽  
S.J. Brookes ◽  
M.S. Duggal
Keyword(s):  
Dental Enamel ◽  
Double Blind ◽  
Fluoride Treatment ◽  
Before And After ◽  
Amine Fluoride ◽  
Knoop Microhardness ◽  
Effect Of Copper ◽  
Removable Appliance

Previous studies have concluded that copper might inhibit enamel demineralization in vitro. Our aim was to assess the effect of copper (Cu2+), with and without amine fluoride, on human dental enamel under cariogenic challenge in situ. In a double-blind randomized four-leg crossover trial, 14 individuals wore a removable appliance containing 2 enamel slabs, 1 containing an artificial caries lesion. During each leg, the appliance was exposed twice daily to one of the test solutions: 1.25 mM CuSO4, amine fluoride (250 ppm F), copper and amine fluoride combined, or a placebo (water). A cariogenic challenge was provided in all cases by 5 daily exposures to 10% sucrose. Slabs were assessed before and after 21 days’ exposure by Knoop microhardness and transverse microradiography. Significantly less demineralization was observed with Cu2+ and fluoride in combination than with fluoride treatment alone (p < 0.05), whereas copper alone had no significant protective effect.

Assessing the Effect of Low Calorie Soda Beverages on Primary Tooth Enamel: An In Vitro Study

2019 ◽  
Vol 43 (3) ◽  
pp. 190-195 ◽  
Author(s):  
Alexandra Korte ◽  
Matina V Angelopoulou ◽  
Georgios Maroulakos
Keyword(s):  
Surface Roughness ◽  
Tooth Enamel ◽  
In Vitro Study ◽  
Primary Tooth ◽  
Dietary Advice ◽  
Low Calorie ◽  
Treatment Groups ◽  
Dental Office ◽  
Before And After

Objective: The purpose of this study was to evaluate the effect of low calorie soda beverages on the enamel of primary teeth. Study Design: Fifty enamel slabs were prepared from twenty primary extracted teeth and were equally divided into five groups: a) 0.9% NaCl (Control), b) Coca-Cola Classic (Sucrose), c) Diet Coke (Aspartame), d) Zevia Cola (Erythritol), e) Coca-Cola Life (Stevia). Each specimen was exposed to the beverage for a total of sixty minutes. Enamel surface roughness was measured before and after the exposures using a LEXT OLS4000 3D Laser Measuring Microscope. Results: All tested sodas resulted to a statistically significant change on the surface roughness of the enamel (p =.000). However, this effect did not differ significantly between the different treatment groups (p =.103). Conclusions: Both regular soda and low calorie soda containing different commercial sweeteners appear to have an effect on the surface morphology of primary tooth enamel. Thus, it is important to discourage the intake of any type of soda as part of the dietary advice provided in the dental office.

scholarly journals Efficiency of different protocols for enamel clean-up after bracket debonding: an in vitro study

2015 ◽  
Vol 20 (5) ◽  
pp. 78-85 ◽  
Author(s):  
Lara Carvalho Freitas Sigilião ◽  
Mariana Marquezan ◽  
Carlos Nelson Elias ◽  
Antônio Carlos Ruellas ◽  
Eduardo Franzotti Sant'Anna
Keyword(s):  
Surface Roughness ◽  
High Speed ◽  
Tooth Enamel ◽  
In Vitro Study ◽  
Moderate Correlation ◽  
Low Speed ◽  
Enamel Roughness ◽  
Intergroup Comparison ◽  
Before And After

Objective: This study aimed to assess the efficiency of six protocols for cleaning-up tooth enamel after bracket debonding.Methods:A total of 60 premolars were divided into six groups, according to the tools used for clean-up: 12-blade bur at low speed (G12L), 12-blade bur at high speed (G12H), 30-blade bur at low speed (G30L), DU10CO ORTHO polisher (GDU), Renew System (GR) and Diagloss polisher (GD). Mean roughness (Ra) and mean roughness depth (Rz) of enamel surface were analyzed with a profilometer. Paired t-test was used to assess Ra and Rz before and after enamel clean-up. ANOVA/Tukey tests were used for intergroup comparison. The duration of removal procedures was recorded. The association between time and variation in enamel roughness (∆Ra, ∆Rz) were evaluated by Pearson's correlation test. Enamel topography was assessed by scanning electron microscopy (SEM).Results:In Groups G12L and G12H, original enamel roughness did not change significantly. In Groups G30L, GDU, GR and GD, a smoother surface (p < 0.05) was found after clean-up. In Groups G30L and GD, the protocols used were more time-consuming than those used in the other groups. Negative and moderate correlation was observed between time and (∆Ra, ∆Rz); Ra and (∆Ra, ∆Rz); Rz (r = - 0.445, r = - 0.475, p < 0.01).Conclusion:All enamel clean-up protocols were efficient because they did not result in increased surface roughness. The longer the time spent performing the protocol, the lower the surface roughness.

scholarly journals Effect of immersion in various disinfectant solutions on the properties of a heat-cured acrylic resin

2019 ◽  
Vol 67 ◽  
Author(s):  
Cláudia Jiménez PEREIRA ◽  
Bruna GENARI ◽  
Vicente Castelo Branco LEITUNE ◽  
Fabrício Mezzomo COLLARES ◽  
Susana Maria Werner SAMUEL
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Acrylic Resin ◽  
Distilled Water ◽  
Medium Term ◽  
Domestic Use ◽  
Knoop Microhardness ◽  
Level Of Significance ◽  
Microhardness Tester

ABSTRACT Objective: The aim of the present study was to evaluate the influence, of immersion in different disinfectant solutions, on microhardness and surface roughness of a heat-cured acrylic resin. Methods: Specimens were immersed in distilled water, commercial vinegar for domestic use, sodium hypochlorite and hydrogen peroxide, for 150 hours or 300 hours (n=10). After periods of immersion, Knoop microhardness and surface roughness were evaluated using a microhardness tester and a roughness tester, respectively. The data were analyzed using two-way ANOVA and Holm-Sidak, at a level of significance of 5%. Results: The microhardness values ranged from 16.90 ± 0.33 to 17.80 ± 0.51 and roughness values from 0.05 ± 0.01 to 0.08 ± 0.02. There is no difference in microhardness and roughness between groups and times (p>0.05). Conclusion: Within the limitations of this study, it is possible to conclude that vinegar and hydrogen peroxide, as alternative disinfectant solutions for acrylic resin devices, did not promote deleterious effects on microhardness and polishing of a heat-cured acrylic resin used for the fabrication of prostheses, neither in the medium term nor the long term.

scholarly journals Effect of violet led associated with low-concentration hydrogen peroxide on enamel surface roughness

2020 ◽  
Vol 19 ◽  
pp. e209197
Author(s):  
Nathalia Eugenio ◽  
Innocenzo Scandiffio ◽  
Marcia Hiromi Tanaka ◽  
Ana Luisa Botta Martins de Oliveira ◽  
Renata Siqueira Scatolin
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Morphological Analysis ◽  
Tooth Enamel ◽  
Enamel Surface ◽  
Tooth Bleaching ◽  
Bleaching Treatment ◽  
One Way Anova ◽  
Scanning Electron

Aim: The present study aimed to assess in vitro the effect ofviolet LED in tooth bleaching techniques associated or not withlow-concentration hydrogen peroxide gel on enamel surfaceroughness. Methods: Fifty-two enamel fragments of bovineteeth were flattened and polished (4x4x3 mm) and dividedinto four groups according to bleaching treatment: VL- VioletLED; HP- 7.5% hydrogen peroxide; HP+VL- 7.5% hydrogenperoxide + violet LED; C- No bleaching (control). Before thetreatments, all specimens were immersed in 20 mL of blacktea for six days, changing solutions every 24 h to simulatethe staining of specimens. Forty fragments were used toanalyze surface roughness (n=10) and 12 fragments wereused for the morphological analysis (SEM) (n=3). Results:The data were submitted to one-way ANOVA and a post-hocTukey test. The lower roughness values was observed for thegroup that did not receive bleaching treatment (C), differingsignificantly only from the group bleached with 7.5% hydrogenperoxide + violet LED (HP+VL) (p=0.0077). The remaininggroups did not show significant differences in roughnessvalues (p>0.05). The scanning electron microscopy analysisshowed irregularities on the enamel surface regardless ofthe treatment received. Conclusion: The results showedthat bleaching treatments with violet LED associated withlow-concentration hydrogen peroxide gels (7.5%) increasethe surface roughness of tooth enamel.

scholarly journals Evaluation of the Effect of a Home Bleaching Agent on Surface Characteristics of Indirect Esthetic Restorative Materials—Part II Microhardness

2014 ◽  
Vol 15 (4) ◽  
pp. 438-443 ◽  
Author(s):  
Mahroo Vojdani ◽  
Kianoosh Torabi ◽  
Sasan Rasaeipour ◽  
Safoura Ghodsi ◽  
Amir Ali Reza Khaledi
Keyword(s):  
Surface Preparation ◽  
Surface Characteristics ◽  
Distilled Water ◽  
Bleaching Agent ◽  
Reinforced Composite ◽  
Restorative Materials ◽  
Most Significant Change ◽  
Knoop Microhardness ◽  
Negative Controls

ABSTRACT Background The exponential usage of esthetic restorative materials is beholden to society needs and desires. Interaction between the bleaching agents and the esthetic restorative materials is of critical importance. Aim This in vitro study has been conducted to evaluate the effect of a home bleaching agent, carbamide peroxide (CP) 38%, on the microhardness of the fiber reinforced composite (FRC), overglazed, autoglazed, or polished porcelain specimens. Materials and methods For overglazed, autoglazed, polished ceramics and also FRC cylindrical specimens (n = 20 per group) were prepared. The specimens were stored in distilled water at 37°C for 48 hours prior to testing. Six samples from each group were selected randomly as negative controls which were stored in distilled water at 37°C that was changed daily. CP 38% was applied on the test specimens for 15 minutes, twice a day for 14 days. By using Knoop-microhardness tester microhardness testing for baseline, control and test specimens was conducted. Data were statistically analyzed using paired t-test, Mann- Whitney test, and Kruskal-Wallis test. Results Home bleaching significantly decreased the surface microhardness of all the test samples (p < 0.05), whereas the control groups did not show statistically significant changes after 2 weeks. The polished porcelain and polished composite specimens showed the most significant change in microhardness after bleaching process (p < 0.05). Conclusion Although the type of surface preparation affects the susceptibility of the porcelain surface to the bleaching agent, no special preparation can preclude such adverse effects. Clinical Significance The contact of home bleaching agents with esthetic restorative materials is unavoidable. Therefore protecting these restorations from bleaching agents and reglazing or at least polishing the restorations after bleaching is recommended. How to cite this article Torabi K, Rasaeipour S, Ghodsi S, Khaledi AAR, Vojdani M. Evaluation of the Effect of a Home Bleaching Agent on Surface Characteristics of Indirect Esthetic Restorative Materials — Part II Microhardness. J Contemp Dent Pract 2014;15(4):438-443.

scholarly journals The difference of surface coarseness of high-copper amalgam restoration material before and after 38% hydrogen peroxide application by in vitro in-office bleaching technique

2007 ◽  
Vol 19 (2) ◽  
Author(s):  
Nurmala Gustina ◽  
Setiawan Natasasmita ◽  
Dudi Aripin
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Effective Agent ◽  
Amalgam Restoration ◽  
High Copper ◽  
Significant Difference ◽  
Before And After ◽  
The Difference ◽  
Amalgam Restorations

Hydrogen peroxide is an effective agent to take off tooth colouring. This bleaching agent can cause microstructural change on amalgam restoration surfaces. The aim of this research is to know the difference of surface roughness of high-copper amalgam restoration materials before and after 38% hydrogen peroxide application by in-office bleaching technique. The sample was used consist of ten specimens of high-copper amalgam restorations which was applied by hydrogen peroxide 38%. The surface roughness was measured by the surface tester (Surtronic 3P). The result of this research was reached by t-test paired calculation is the differences of surface roughness of amalgam restorations before and after first 15 minutes either second 15 minutes hydrogen peroxide 38% application didn’t show significant differences. The conclusion of this research is no statistically significant difference of surface roughness of high-copper amalgam restoration materials before and after 38% hydrogen peroxide application by in-office bleaching technique.

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