scholarly journals Evaluation of the effect of tooth polishing on color stability after in-office bleaching treatment

2020 ◽  
Vol 49 ◽  
Author(s):  
Luís Felipe ESPÍNDOLA-CASTRO ◽  
Pamella Robertha Rosselinne Paixão CELERINO ◽  
Tácyla Alves do NASCIMENTO ◽  
Gabriela Queiroz de Melo MONTEIRO ◽  
Tereza Cristina CORREIA
Keyword(s):  
Red Wine ◽  
Dental Enamel ◽  
Color Stability ◽  
Tooth Bleaching ◽  
Dental Tissues ◽  
Bleaching Procedure ◽  
Two Samples ◽  
Before And After ◽  
The Difference ◽  
Bleaching Treatment

Abstract Introduction One of the most commonly used corrective methods for staining teeth is tooth bleaching. However, subclinical alterations may occur in the micromorphology of dental tissues during the bleaching procedure, such as increases in porosity and surface roughness. Consequently, dental enamel may become more permeable and susceptible to staining. Objective To evaluate the influence of tooth polishing after in-office bleaching treatment on color stability. Material and method Thirty-three extracted human molars were used. The teeth were cut in the mesiodistal direction to obtain two samples per tooth (total of 66). The samples were randomly divided into six groups (n=11). Before and after the bleaching treatment, the lightness of the samples and change in lightness (∆L) were determined with a digital spectrophotometer (Easy Shade). The samples were bleached with 35% hydrogen peroxide (three sessions weekly). Three groups were submitted to polishing with felt discs and polishing paste after each session. To simulate the oral conditions during the consumption of colored beverages, the samples were submitted to alternating cycles of immersion in staining solutions (coffee, red wine, and Coca Cola). Result Polishing resulted in an increase of mean lightness of 4.49 in the red wine group, 2.73 in the coffee group, and 4.08 in the cola group. The difference was significant in the red wine group (p<0.022), but not in the coffee or cola group. Conclusion Polishing after in-office bleaching using felt discs and polishing paste can reduce the degree of pigment impregnation in patient with red wine rich diet.

Effect of Liquid Polishing System on Color Stability of Bleached Enamel

2013 ◽  
Vol 804 ◽  
pp. 141-145
Author(s):  
Xiu Lan Chen ◽  
Huang Qin Chen
Keyword(s):  
Red Wine ◽  
Color Change ◽  
Color Stability ◽  
Control Groups ◽  
Significant Difference ◽  
Before And After ◽  
Total Color Change ◽  
Post Hoc ◽  
And Control ◽  
One Way Anova

The purpose of this study was to investigate the effect of liquid polishing system (BisCover) on color stability of the bleached enamel upon exposure to a staining agent-red wine. Forty specimens were prepared. They were divided into 2 groups and different procedures, including only bleaching with Opalescence PF (PF) or Opalescence regular (R) gels, and application of BisCover after blaeching (PF-B, R-B) were used. Unbleached specimens were served as control groups (control-1 and control-2). The specimens were stored for 48 h in red wine. The color of all specimens was measured before and after exposure with a spectrophotometer, and total color change (ΔE*) were calculated. The data were analyzed with a one-way ANOVA and the means were compared by Tukeys post hoc analysis (α=0.05). PF-B and R-B groups demonstrated significantly less color change than PF and R groups. the control-1 and control-2 groups had the least color change. No significant difference were observed between PF and R group. BisCover improved the color stability of bleached enamel in red wine.

The Effect of Bleaching Agents on the Color Stability of Ceromer and Porcelain Restorative Materials In Vitro

2012 ◽  
Vol 38 (1) ◽  
pp. E1-E8 ◽  
Author(s):  
HB Kara ◽  
F Aykent ◽  
B Ozturk
Keyword(s):  
Color Change ◽  
Glass Ceramics ◽  
In Vitro Study ◽  
Color Stability ◽  
Color Changes ◽  
Bleaching Procedure ◽  
Significant Difference ◽  
Restorative Materials ◽  
The Difference

SUMMARY Purpose The aim of this in vitro study was to determine the color changes of five different restorative materials after exposing these materials to two different home bleaching agents. Methods This study applied bleaching agents to an ultralow-fusing porcelain, a low-fusing porcelain, two types of heat-pressed glass ceramics, and a ceromer. A total of 24 disc-shaped specimens were fabricated (with a diameter of 10 mm and a thickness of 2 mm) from each material (n=12). The initial color measurements were taken with a spectrophotometer. The first set of specimens were bleached with 10% hydrogen peroxide (HP) for one hour daily for 10 days. The other set of specimens were bleached with 10% carbamide peroxide (CP) bleaching gel for eight hours daily for 14 days. Data were analyzed with the one-way analysis of variance and Kruskal-Wallis statistical test. The difference in the prebleaching and postbleaching color of each material was considered to be statistically significant at p &lt; 0.05. Results The study found a statistically significant difference among the color changes of the test groups after exposing them to both bleaching agents (p&lt;0.05). Appreciable color change was observed in the Estenia (ΔE=3.99) specimens that were bleached with the HP, and noticeable color changes were observed in the Estenia (ΔE=1.89) and IPS Empress 2 (ΔE=1.66) groups when they were treated with the CP. Conclusions Restorations (especially polymer-containing restorative materials) should be protected before any bleaching procedure due to the high risk of color change.

scholarly journals Color stability of artificial teeth after exposure to acid and staining agents

2015 ◽  
Vol 18 (1) ◽  
pp. 60 ◽  
Author(s):  
Mateus Guimaraes Lage Reggiani ◽  
Fernanda Alves Feitosa ◽  
Rodrigo Máximo De Araújo
Keyword(s):  
Red Wine ◽  
Artificial Saliva ◽  
Soft Drink ◽  
Color Stability ◽  
Lemon Juice ◽  
Color Variation ◽  
Color Measurement ◽  
Oral Rehabilitation ◽  
Before And After ◽  
Artificial Teeth

<p><strong>Objective: </strong>Changes in color of artificial teeth mainly occur due to ingestion of beverages and use of products for cleaning and disinfection. The more aggressive solutions must be identified and the patient provided with explanations in order to avoid or reduce the frequency of their use, to a higher longevity of the denture. The purpose of this study was to evaluate the changes in color of artificial teeth before and after immersion in beverages and disinfectants. <strong>Material and Methods: </strong>96 artificial resin teeth were randomly divided into 8 groups. Each group was immersed for 10 min into a test solution (coffee, lemon juice, chlorhexidine gluconate, red wine, cola-based soft drink, vinegar or antiseptic with and without alcohol) and then the specimens were stored in artificial saliva for 23 h and 50 min, completing a period of 24 h. This procedure was performed for 14 consecutive days and after this period the second color measurement was made.The data obtained with the spectrophotometer using the CIEL*a*b* system were statistically analyzed using ANOVA non parametric, Kruskal-Walis and the Dunn test. <strong>Results: </strong>There were found differences in color variation for each experimental group after the challenge. statistically significant differences were found between the coffee, red wine and lemon juice groups. <strong>Conclusion: </strong>All the substances changed the color of artificial teeth; coffee was the substance that caused most staining of artificial teeth, altering color and luminosity; the oral antiseptics with and without alcohol promoted whitening of the artificial teeth.</p><p class="western" align="justify"><span style="font-family: Arial, serif;"><strong>Keywords: </strong></span><span style="font-family: Arial, serif;"><span lang="en-US">Artificial tooth; Denture; Oral rehabilitation; Staining.</span></span></p>

scholarly journals Management control levers in hospitals: the influence of accreditation on other management control systems

2020 ◽  
pp. 239-247
Author(s):  
Marcia-Zanievicz Da Silva ◽  
Micheli-Aparecida Lunardi ◽  
Alyne-Cecilia Serpa-Ganz ◽  
Vinícius-Costa Da Silva-Zonatto
Keyword(s):  
Control Systems ◽  
Health Sector ◽  
Management Control ◽  
Management Control Systems ◽  
Interactive Control ◽  
Scarce Resources ◽  
Two Samples ◽  
Before And After ◽  
The Face ◽  
The Difference

The objective of this study is to identify the influence of accreditation on management control systems (MCS) before and after implementation. A survey was performed, with a sample of 92 respondents (professionals responsible for implementing accreditation) and a t-test was used to evaluate the difference between the two samples (before and after accreditation). The results show that after accreditation, management control systems (beliefs, boundary, diagnostic, and interactive control systems) had seen significant improvements, leading to better management and quality of the health services provided. In the face of growing demands from the health sector, analyzing the balanced use of management techniques that improve organizational control in companies is expected to contribute to better service delivery and maximization of generally scarce resources.

Effect of Sodium Tripolyphosphate on Color Stability of In-Office Bleached Teeth

2013 ◽  
Vol 804 ◽  
pp. 57-61
Author(s):  
Huang Qin Chen ◽  
Bin Huang
Keyword(s):  
Red Wine ◽  
Color Change ◽  
Sodium Tripolyphosphate ◽  
Color Stability ◽  
Positive Control ◽  
Negative Control ◽  
Significant Difference ◽  
Before And After ◽  
Total Color Change ◽  
Post Hoc

The purpose of this study was to investigate the effect of polyanionsodium tripolyphosphate (STP) on color stability of the bleached enamel upon exposure to a staining agent-red wine. Thirty specimens were prepared and bleached with 35% hydrogen peroxide (HP). Then, they were divided into three groups and immersed in different experiment solutions, including distilled and deionized water (DDW, negative control), 2% STP (PH 9.0) and 1000 ppm NaF aq. (positive control), before and after red wine stain challenge, 3 times per day. The color of all specimens was measured before and after exposure to red wine with a spectrophotometer, and total color change (ΔE*) were calculated. The data were analyzed with a one-way ANOVA and the means were compared by Tukeys post hoc analysis (α=0.05). STP treatment group demonstrated significantly less color change than DDW and NaF groups (p<0.05). No significant difference was observed between DDW and NaF group. It can be concluded that the staining susceptibility of bleached enamel decreased after application of polyanion sodium tripolyphosphate.

scholarly journals In-Vitro Silanization of Dental Enamel to Prevent Demineralization

2021 ◽  
pp. 353-363
Author(s):  
José R. Gutiérrez-Camacho ◽  
Luis Alejandro Aguilera-Galavíz ◽  
G. Sánchez-Balderas ◽  
Gabriela Palestino ◽  
Norma Verónica Zavala-Alonso ◽  
...  
Keyword(s):  
Citric Acid ◽  
Acidic Medium ◽  
Tooth Enamel ◽  
Dental Enamel ◽  
Hydrophobic Modification ◽  
Dental Tissues ◽  
Before And After ◽  
Topical Fluoride ◽  
Scanning Electron

Introduction. Caries is a multifactorial disease that can negatively affect dental tissues through the demineralization process, which produces acids deriving from the metabolism of carbohydrates. Some strategies to prevent this process have been proposed, such as topical fluoride application, resin-based restorations, pit and fissures sealers, infiltrated resins, vaccines, mouthwashes, and several brushing techniques. Objective. To evaluate in vitro enamel hydrophobic modification as a method of prevention against demineralization. Materials and Methods. A descriptive and comparative study was carried out. Thirty premolars extracted for orthodontic reasons were obtained, encapsulated in epoxy resin, sectioned, and sanded to obtain specimens 3mm in thickness. The samples were pretreated with NaOCl and EDTA, incubated with 1 and 4% octadeyltrichlorosilane (OTS) or with 3 and 6% octadecyltriethoxysilane (TEOS) for 5min and for 8h. Subsequently, the samples were immersed in citric acid for 2 months. The samples were analyzed by their contact angle, infrared spectroscopy, scanning electron microscopy, atomic and confocal force, before and after treatment in citric acid. Results. The samples coated with 1 and 4% OTS for 5min and 8h kept the silanizing agent on their surface after 2 months in citric acid. The treatment with TEOS was only effective at 6% with a reaction time of 5min. Conclusions. The modification with 1 and 4% OTS protects the surface of the tooth enamel from demineralization in acidic medium. The results indicate that treatment with 4% OTS is effective from 5min, which makes it appropriate in clinical practice.

scholarly journals The Impact of Artificial Aging on the Color Stability and Hardness of Nanocomposite Resin

2021 ◽  
Vol 8 ◽  
Author(s):  
Likai Wang ◽  
Yan Zheng
Keyword(s):  
Artificial Aging ◽  
Color Stability ◽  
Color Difference ◽  
Before And After ◽  
Group A ◽  
Hardness Change ◽  
The Difference ◽  
American Society ◽  
Group B ◽  
The Impact

Objective: This study aimed to investigate the impact of artificial aging on the color stability and hardness of nanocomposite resin.Methods: Four nanocomposite resin materials were used: Filtek Z350 XT (FZ), Synergy D6 (SD), Grandio (GD), and Clearfil Majesty Esthetic (CM). Thirty specimens were created from each material, which were divided into three (A,B,C) groups of 10 specimens each. For each material, the values of visual lightness (L*), degree of redness and greenness (a*), and degree of yellowness and blueness (b*) of the specimens in group A before and after aging, as well as the hardness of the specimens in group B before aging and in group C after aging, were measured. The American Society for Testing and Materials (ASTM) G155 Cycle 1 standard was adopted to test the aging of the specimens. The color difference (ΔE00) value and hardness difference (ΔH) value of the specimens before and after aging were calculated.Results: Aging was found to have an impact on the ΔE00 values of the resin materials in each group (H = 17.6, p = 0.001), and the hardness of the specimens in each group after artificial aging was significantly higher than before aging (p &lt; 0.05). The difference in ΔE00 between the FZ group and the SD, GD, and CM groups was statistically significant (p &lt; 0.05). The FZ group had the highest ΔE00 values. There was no correlation between ΔE00 and the hardness change percentage after aging (r = 0.114).Conclusion: Among the four nanocomposite resins tested in this study, except for Filtek Z350 XT’s ΔE00 values (&gt;1.8) in the clinically unacceptable range, the remaining three kinds of resin ΔE00 values (&lt;1.8) were all in the clinically acceptable range. The hardness of the four nanocomposite resins increased after aging. The results of the present study revealed that there was no correlation between ΔE00 and hardness change percentage in the four nanocomposite resin materials after aging.

scholarly journals Direct Radiotherapy-Induced Effects on Dental Hard Tissue in Combination With Bleaching Procedure

2021 ◽  
Vol 2 ◽  
Author(s):  
Eva Klarić Sever ◽  
Andro Tarle ◽  
Majana Soče ◽  
Timor Grego
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Repeated Measures ◽  
Morphological Properties ◽  
Permanent Teeth ◽  
Control Group ◽  
Carbamide Peroxide ◽  
Dental Tissues ◽  
Bleaching Procedure ◽  
Bleaching Treatment

Introduction: The aim of this study was to evaluate the effects of radiation and tooth bleaching on the physical and morphological properties of enamel and dentin on permanent teeth.Materials and Methods: Eighty fresh, non-carious third molars were used in this study. Before cutting the crown in half, the teeth samples were randomly allocated to treatment and control groups by using a lottery method. The first group (n = 20) underwent standard radiation protocol (2 Gy/fraction/day, 5 days/week) with bleaching treatment afterward using 16% carbamide peroxide gel, the second group (n = 20) underwent standard radiation protocol with afterward bleaching treatment using 38% hydrogen peroxide, the third group (n = 20) underwent a short, one strong, experimental dose of 70 Gy with afterward bleaching treatment using 16% carbamide peroxide gel, and the fourth group (n = 20) underwent one strong, experimental dose of 70 Gy with afterward bleaching treatment using 38% hydrogen peroxide gel. Groups 5–8 (n = 20) served as control as they underwent only bleaching treatment. Vickers microhardness and surface roughness were performed before (initial) and after irradiation and before bleaching or after only bleaching. The effects of irradiation and bleaching on microhardness (or roughness) of enamel and dentin were analyzed in the repeated-measures ANOVA model.Results: Enamel microhardness after experimental single 70-Gy irradiation or after standard radiation protocol and bleaching with 16 or 38% gel was not statistically significant from microhardness in the control group (p &gt; 0.05). There was a statistically significantly greater reduction in the average microhardness of enamel and dentin during bleaching with 38% gel compared to 16% for both radiation protocols (p &lt; 0.001). After experimental 70-Gy irradiation and bleaching, a 16% statistically significant increase in surface roughness was found for enamel (p = 0.006) and dentin (p = 0.018), while this was not recorded for 38% gel. There was a statistically significantly greater increase in the average roughness of enamel and dentin during bleaching with 38% gel compared to 16% (p &lt; 0.001) for both radiation protocols.Conclusions: Directly induced radiation leads to potential damage of hard dental tissues, which can be further damaged by additional bleaching. If teeth whitening is necessary after irradiation, it is suggested to use lower concentrations of whitening gels.

Effect of air-polishing on properties of nanocomposite submitted to coffee, red wine and cigarette smoke

2018 ◽  
Vol 17 ◽  
pp. 1-10
Author(s):  
Paula Mathias ◽  
Thayz Mota de Souza Cunha ◽  
Isadora Almeida Rios Rocha ◽  
Lívia Andrade Vitória ◽  
Caroline Mathias ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Cigarette Smoke ◽  
Repeated Measures ◽  
Red Wine ◽  
Color Stability ◽  
Smoke Exposure ◽  
Cigarette Smoke Exposure ◽  
Distilled Water ◽  
Air Polishing ◽  
Before And After

AIM: The aim of this study was to evaluate the surface roughness and the color stability of nanocomposite exposed to the sodium bicarbonate air-polishing (SBAP) followed by red wine, coffee and cigarette smoke exposure. MATERIALS AND METHODS: 64 nanocomposite specimens were prepared and allocated in 8 groups: G1 (SBAP + distilled water), G2 (SBAP + coffee), G3 (SBAP + red wine), G4 (SBAP + cigarette smoke), G5 (distilled water), G6 (coffee), G7 (red wine) and G8 (cigarette smoke). The surface roughness was evaluated in three periods: before and after SBAP and after exposuring to agents tested. The color was evaluated according to CIEL*a*b* parameters using reflection spectrophotometer in two moments: initial and 30 days after the exposure to staining agents. Data were subjected to three-way repeated measures ANOVA and Tukey’s test (5%). RESULTS: The results showed a higher surface roughness of the nanocomposite submitted only to the SBAP and those exposed to the SBAP followed by exposure to the coffee or wine solution. The previous application of SBAP followed by cigarette smoke exposure did not increase the roughness of nanocomposite. The SBAP procedure just increased the staining for cigarette smoke group. CONCLUSION: The SBAP increases resin surface roughness, which worsens when there is exposure to coffee and red wine solution. In addition, SBAP may also provide increased staining of nanocomposites exposed to cigarette smoke.

scholarly journals Efecto de la convergencia a normas internacionales de información financiera en empresas cotizantes de la bolsa de valores de Colombia

AD-minister ◽  
2019 ◽  
pp. 77-92
Author(s):  
Liliana Elizabeth Ruiz Acosta ◽  
David Andrés Camargo Mayorga ◽  
Octavio Cardona García
Keyword(s):  
Financial Reporting ◽  
Stock Exchange ◽  
Financial Indicators ◽  
Return On Equity ◽  
Operating Income ◽  
Financial Reporting Standards ◽  
Operating Profit ◽  
Two Samples ◽  
Before And After ◽  
The Difference

The purpose of this document is to analyze the effect of adopting the International Financial Reporting Standards (IFRS), which is a compulsorily requirement to be complied with as of 2015, for companies listed on the Colombian Stock Exchange (BVC by its acronym in Spanish). For the purposes of this study, two samples were used. The first one, with 52 Colombian companies whose financial indicators such as Return on Equity (ROE), Operating Profit Margin (OPM) and Return on Invested Capital (ROIC) were obtained from the accounting information, and where the mean difference was applied, (These companies corresponded to the year 2014 before and after the IFRS.) The second sample had 32 companies. Their level of leverage, ordinary income, operating income, and profit and loss for the year were analyzed to determine the effects of these variables on their market capitalization, using the difference in differences method, taking 2014 as the control year without IFRS and 2015 as the year of treatment with IFRS. The findings show, that in the 52 companies studied, adopting the standards did not signal changes in financial indicators before and after IFRS, as does the stock market value in the sample of 32 companies.

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