scholarly journals Effect of Four Bleaching Regimens on Color Changes and Microhardness of Dental Nanofilled Composite

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Simone Xavier Silva Costa ◽  
Anne Buss Becker ◽  
Alessandra Nara de Souza Rastelli ◽  
Leonor de Castro Monteiro Loffredo ◽  
Marcelo Ferrarezi de Andrade ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Vickers Hardness ◽  
Artificial Saliva ◽  
Control Group ◽  
Carbamide Peroxide ◽  
Mean Values ◽  
Color Changes ◽  
Before And After ◽  
And Control ◽  
Cielab Color

Objective. The purpose of this study was to compare the color changes and microhardness of a nanocomposite after four bleaching regimens.Materials. Twenty-five specimens(n=25)were made with a nanocomposite resin (Filtek Supreme XT). The specimens were divided into five groups equally(n=5): bleaching groups and control group, as follows: G1: artificial saliva at37∘C; (control) G2: hydrogen peroxide (HP) at 7%; G3: hydrogen peroxide (HP) at 35%; G4: carbamide peroxide (CP) at 10%; G5: carbamide peroxide (CP) 35%. Color measurements were made with spectrophotometer using CIELAB color scale. The Vickers hardness (VHN) measurements were performed at the top surface. The data were analyzed with two-way Analysis of Variance.Results.ΔE and VHN mean values into the groups were not statistically different, however, the VHN mean values before and after storage and bleaching showed statistically significant differences.Conclusion. Nanocomposite samples showed no significant alteration (color and microhardness) after bleaching. Thus, no replacement of restorations is required after bleaching.

scholarly journals Effect of Short- and Long-term Use of Home and In-Office Bleaching with Carbamide Peroxide and Hydrogen Peroxide on Bleaching with Carbamide Peroxide and Hydrogen Peroxide on Enamel Microhardness Enamel Microhardness

2020 ◽  
Vol 27 (2) ◽  
Author(s):  
Nazila Ameli ◽  
◽  
Niloofar Kianvash Rad ◽  
Farzane Nikpour ◽  
Raheb Ghorbani ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Dental Treatment ◽  
Artificial Saliva ◽  
Tooth Bleaching ◽  
Control Group ◽  
Bleaching Agent ◽  
Carbamide Peroxide ◽  
Dental Procedures ◽  
Before And After ◽  
At Home

Bleaching is a well-known esthetic dental treatment performed to lighten the tooth shade. Among different cosmetic dental procedures, including direct and indirect tooth-colored restorations, bleaching is likely the most conservative approach. Bleaching has been accepted well by patients and proven as a safe and effective approach. Objective: Tooth bleaching can be conducted at home or in offices. This study was performed to compare the enamel microhardness before bleaching and one and eight weeks after the application of different bleaching agents. Methods: Forty human premolars were randomly divided into four groups, and their buccal surface underwent a Vickers microhardness test before and after bleaching. Bleaching was performed with 40% hydrogen peroxide (HP) in-office bleaching agent (n = 10), 15% HP at-home bleaching agent (n = 10), and 15% carbamide peroxide (CP) at-home bleaching agent (n = 10) for two weeks. Ten samples were stored in artificial saliva and set as the control group. The microhardness of the samples was measured again one and eight weeks after bleaching. Results: The microhardness significantly decreased in the four groups one week after bleaching. Conclusion: The enamel microhardness was temporarily decreased by in-office bleaching. However, the microhardness increased with time and returned to the baseline value. Although the enamel microhardness initially reduced, it increased eight weeks after 15% CP at-home bleaching agent was applied.

scholarly journals Effect of Different Bleaching Methods on Optical Behaviors of CAD/CAM Ceramics

2021 ◽  
Vol 13 (4) ◽  
pp. 113-118
Author(s):  
Saeed Nikanjam ◽  
Samaneh Abbasi ◽  
Sara Khazaei
Keyword(s):  
Hydrogen Peroxide ◽  
Significant Influence ◽  
Color Change ◽  
Mean Value ◽  
Carbamide Peroxide ◽  
Mean Values ◽  
Before And After ◽  
Cad Cam ◽  
The Mean ◽  
Final Color

Background: The present study aimed to survey the influence of two different bleaching techniques on changes of color, translucency, and whiteness of the four CAD/CAM materials. Methods: The monolithic blocks of Vita Suprinity, Vita Enamic, IPS e.max CAD, and Katana Zirconia were sectioned to discs with thickness of 2 mm (n=30 / each group). Samples from each type of ceramic were assigned to three subgroups: 1) the 40% hydrogen peroxide for 20 minutes; 2) the 16% carbamide peroxide for three hours/day for 2 weeks; and 3) the control. Then CIELab coordinates of each sample were evaluated before and after the intervention by a spectrophotometer. Final color change (ΔE), Whiteness (ΔWI D), and Translucency Parameter (ΔTP) were calculated. Two-way ANOVA test was adopted to analyze the data (α=0.05). Results: Type of ceramic, bleaching subgroups, and interaction between them had a statistically significant influence on mean values of ΔE, ΔWID. The influence of bleaching subgroup on the mean value of ΔTP was also significant (P<0.001). Conclusions: Carbamide peroxide 16% for three hours/day and for two weeks caused the most considerable changes in final color, whiteness, and translucency of the all tested CAD/CAM materials. Maximum color change and whiteness were detected in the Vita Enamic, which were clinically unacceptable.

scholarly journals Whitening mouthwash containing hydrogen peroxide decreases enamel microhardness in vitro.

2017 ◽  
Vol 16 ◽  
pp. 1-9 ◽  
Author(s):  
Fernando Pelegrim Fernandes ◽  
Cecília Pedroso Turssi ◽  
Fabiana Mantovani Gomes França ◽  
Roberta Tarkany Basting ◽  
Flávia Lucisano Botelho do Amaral
Keyword(s):  
Hydrogen Peroxide ◽  
Repeated Measures ◽  
Artificial Saliva ◽  
Control Group ◽  
Carbamide Peroxide ◽  
Knoop Microhardness ◽  
Bovine Enamel ◽  
Bleaching Treatment ◽  
Over Time

Aim: To assess the effect of a mouthwash containing hydrogen peroxide (HP) on Knoop microhardness (KMH) of bovine enamel. Methods: Fifty-one enamel slabs were polished and divided into groups (n=17), according to the product used during 28 days: HP – mouthwash containing 1,5% of HP (4 min, once/day); CP - 10% carbamide peroxide gel (2 hours/day); AS - no treatment (kept in artificial saliva (AS). Each fragment was submitted to KMH test (three indentations/fragment, with a 50 g load for 5 sec) four times: before (baseline); during (14 and 28 days) and after (7 days immerged in AS) the bleaching treatment. The data were submitted to repeated-measures two-way ANOVA (α=0.05). Results: There was no effect of the interaction between the time and treatment factors (p=0.327). No significant effect was observed from the time factor (p = 0.054). The factor treatment showed significant effect (p =0.002). Regardless of time, the KMH of the enamel submitted to HP was lower than the value observed with the use of CP, which did not differ significantly from the control group (AS). Conclusion: Although there was a trend of decreasing enamel microhardness over time, only the mouthwash containing hydrogen peroxide had a significant effect.

Effect of Bleaching on Color Change of Stained Resin Composites

2017 ◽  
Vol 751 ◽  
pp. 636-642
Author(s):  
Ratcha Raksakmanut ◽  
Ampaporn Nithipratheep ◽  
Ornjira Weeriyanan ◽  
Panida Pittayaporn ◽  
Waivich Komonpale ◽  
...  
Keyword(s):  
Red Wine ◽  
Color Change ◽  
Artificial Saliva ◽  
Resin Composites ◽  
Carbamide Peroxide ◽  
Spectrophotometric Measurement ◽  
Bleaching Process ◽  
Color Changes ◽  
Color Differences ◽  
Before And After

The aim of this study was to evaluate the effects of bleaching on color change of stained resin composites. Ninety disk-shaped specimens were prepared with 3 different composite materials (Estelite ∑ Quick, Premise, and Filtek Z350 XT). After stored in artificial saliva at 37°C for 24 hours in an incubator, the 30 specimens of each material were divided into 3 subgroups and immersed in either coffee, red wine, or artificial saliva (control) at 37°C. After 24 days, spectrophotometric measurement was performed. After the staining process, the bleaching agent (Opalescence, 10% carbamide peroxide) was applied to the surface of the specimens, 8 hours per day for 14 days. After the bleaching process, spectrophotometric measurement was performed. The color differences between specimens before and after bleaching were statistically significant (ΔE*ab>3.3) for all composites in the red wine staining. The highest-level color change after bleaching was observed for Filtek Z350 XT in red wine staining, while the least value was found in Estelite ∑ Quick in coffee staining. In summary, color changes of all red wine-stained composites after bleaching were noticeable and have higher level of color change than coffee-stained composites.

scholarly journals Susceptibility of Enamel Treated with Bleaching Agents to Mineral Loss after Cariogenic Challenge

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hüseyin Tezel ◽  
Cigdem Atalayin ◽  
Ozlem Erturk ◽  
Ercument Karasulu
Keyword(s):  
Hydrogen Peroxide ◽  
Inductively Coupled Plasma ◽  
The Other ◽  
Clinical Aspects ◽  
Control Group ◽  
Carbamide Peroxide ◽  
Inductively Coupled ◽  
Plasma Mass Spectrometry ◽  
And Control ◽  
Calcium Loss

Objectives. Controversial reports exist whether bleaching agents cause a susceptibility to demineralization. The aim of this study was to compare the calcium loss of enamel treated with different bleaching agents and activation methods.Method and Materials. The specimens obtained from human premolars were treated in accordance with manufacturer protocols; 10% carbamide peroxide, 38% hydrogen peroxide light-activated, 38% hydrogen peroxide laser-activated, and no treatment (control). After cariogenic challenge calcium concentrations were determined by Inductively Coupled Plasma Mass Spectrometry.Results. No differences were found between the calcium loss of the laser-activated group and 10% carbamide peroxide group (). However, the differences between laser-activated and control groups were statistically significant (). The differences between 10% carbamide peroxide and the control group were not significant (). On the other hand, the light-activated group showed a significantly higher calcium loss compared with the other groups ().Conclusions. The results show that bleaching agents may cause calcium loss but it seems to be a negligible quantity for clinical aspects.

Effects of Time and Perceptual Orientation on Actors' and Observers' Attributions

1984 ◽  
Vol 58 (1) ◽  
pp. 23-30
Author(s):  
Donald S. Martin ◽  
Ming-Shiunn Huang
Keyword(s):  
Video Recording ◽  
Control Group ◽  
Control Groups ◽  
Video Recordings ◽  
Before And After ◽  
Perceptual Orientation ◽  
Initial Difference ◽  
Variety Show ◽  
And Control ◽  
Unrelated Variety

The actor/observer effect was examined by Storms in a 1973 study which manipulated perceptual orientation using video recordings. Storms' study was complex and some of his results equivocal. The present study attempted to recreate the perceptual reorientation effect using a simplified experimental design and an initial difference between actors and observers which was the reverse of the original effect. Female undergraduates performed a motor co-ordination task as actors while watched by observers. Each person made attributions for the actor's behaviour before and after watching a video recording of the performance. For a control group the video recording was of an unrelated variety show excerpt. Actors' initial attributions were less situational than observers'. Both actors and observers became more situational after the video replay but this effect occurred in both experimental and control groups. It was suggested the passage of time between first and second recording of attributions could account for the findings and care should be taken when interpreting Storms' (1973) study and others which did not adequately control for temporal effects.

Antimicrobial Effect of 940 nm Diode Laser based on Photolysis of Hydrogen Peroxide in the Treatment of Periodontal Disease

2018 ◽  
Vol 69 (8) ◽  
pp. 2081-2088 ◽  
Author(s):  
Alin Alexandru Odor ◽  
Edwin Sever Bechir ◽  
Deborah Violant ◽  
Victoria Badea
Keyword(s):  
Hydrogen Peroxide ◽  
Laser Therapy ◽  
Diode Laser ◽  
Antimicrobial Effect ◽  
The Other ◽  
Control Group ◽  
Group 4 ◽  
Periodontal Bacteria ◽  
Severe Periodontitis ◽  
Before And After

Moderate and severe periodontitis represents a challenge in the non-surgical periodontal therapy. Due to the lack of evidence regarding the antimicrobial effectiveness of 940 nm diode laser in periodontal treatment, this study aimed to evaluate the antimicrobial effect of hydrogen peroxide (H2O2) photolysis performed with 940 nm diode laser in the treatment of moderate and severe periodontitis. Twenty-five patients with 100 teeth were selected for this pilot study. The test teeth were randomly assigned to one of the four treatment groups: Group 1: scaling and root planning (SRP) (control group); and the following experimental groups: Group 2: H2O2; Group 3: 940 nm diode laser therapy; Group 4: 940 nm diode laser therapy and H2O2. Clinical examinations, like probing depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) were performed before and after the treatment. The microbiological evaluation, effectuated before and after the treatment, included nine periodontal bacteria species and investigated by means of real-time PCR assay. The clinical and bacterial differences in the tested groups, was assessed between control group and the other three experimental groups, as well as between the experimental groups. The total bacteria load was reduced for all four studied groups. Group 4 (diode laser + H2O2) showed significant bacterial reduction of the major periodontal bacteria like Pg., Tf., Td., Pi., Pm., Fn (p[0.001) than the other 3 groups (p]0.001). Also the periodontal clinical parameters, like PD, CAL and BOP showed a significant reduction after the photolysis of H2O2 with the 940 nm diode laser (p[0.001). Differences between tested groups showed a significant beneficial results in regard to Group 4.It is suggested that the photoactivation of H2O2 with the 940 nm diode laser can be used successfully in adjunctive to the non-surgical periodontal treatment as a bactericidal tool.

Melatonin Improves Erythropoietin Hyporesponsiveness via Suppression of Inflammation

2019 ◽  
Vol 14 (3) ◽  
pp. 203-208
Author(s):  
Evan Noori Hameed ◽  
Haydar F. Hadi AL Tukmagi ◽  
Hayder Ch Assad Allami
Keyword(s):  
Iron Status ◽  
Transferrin Saturation ◽  
Control Group ◽  
Base Line ◽  
Inadequate Response ◽  
Inflammatory Parameters ◽  
Tnf Α ◽  
Before And After ◽  
And Control ◽  
Controlled Clinical Study

Background: Inadequate response to Erythropoietin Stimulating Agents (ESA) despite using relatively larger doses regimen represents a potential risk factor of Cardiovascular (CV) related mortality in addition to health-care economic problems in anemic patients with Chronic Kidney Disease (CKD). Erythropoietin (EPO) hyporesponsiveness related to inflammation has been increased progressively. Melatonin is well known as a potent anti-inflammatory agent. Therefore, the current study was designed to evaluate whether melatonin could improve anemic patients response to EPO. Methods: This single controlled clinical study was carried out in 41 CKD patients with hemoglobin (Hb) levels less than 11g/dl divided randomly in a 1:1 ratio into 2 groups; treatment group who received 5mg melatonin plus their regular treatments and control group who received their regular treatments only. Hematological and iron status parameters include Hb level, serum iron (S. iron), Transferrin Saturation Ratio (TSAT) and serum ferritin (S. ferritin) in addition to inflammatory parameters that include tissue necrotic factor alfa (TNF-α), interleukin-1beta (IL-1β) and interleukin-6 (IL-6) determined before and after 12 weeks of treatment. Results: Melatonin remarkably increases the Hb level with a significant increase in S. iron and TSAT compared to baseline. The elevation of S. iron and TSAT was significantly higher in the melatonin group. Additionally, all inflammatory markers estimated were reduced significantly by melatonin compared to base line and control group. Conclusion: The results of the current study showed that melatonin has an advantageous effect on improving EPO response in anemic patients with CKD.

scholarly journals Toe Clearance Rehabilitative Slippers for Older Adults With Fall Risk: A Randomized Controlled Trial

2021 ◽  
Vol 12 ◽  
pp. 215145932110291
Author(s):  
Atsuko Satoh ◽  
Yukoh Kudoh ◽  
Sangun Lee ◽  
Masumi Saitoh ◽  
Miwa Miura ◽  
...  
Keyword(s):  
Older Adults ◽  
Fall Risk ◽  
Controlled Trial ◽  
Intervention Group ◽  
Berg Balance Scale ◽  
Control Group ◽  
Mobility Assessment ◽  
Before And After ◽  
Day Services ◽  
And Control

Introduction: To evaluate fall-prevention rehabilitative slippers for use by self-caring, independent older adults. Materials and Methods: This assessor-blinded, randomized, and controlled 1-year study included 59 self-caring, independent participants (49 women) who attended day services. The mean age of participants was 84.0 ± 5.3 years. Participants were randomly selected from 8 nursing homes. We tested slippers top-weighted with a lead bead (200, 300, or 400 g). Intervention group participants walked while wearing the slippers for 10-20 min, 1-3 days/week at the day service center. Fall risk was measured using the Berg Balance Scale and the Tinetti Performance-Oriented Mobility Assessment (POMA) before and at 3-month intervals after the intervention/control phase. Results: After 12 months, the intervention group demonstrated significant improvement. Berg Balance and POMA compared to the control group ( p < .05 p < .01, respectively). Mobility scores improved significantly for both measurements in the intervention group before and after ( p < .01), but the control group had significantly lower scores. Discussion: Overall, falls decreased in the intervention group from 10 to 7, and control group falls increased from 9 to 16 ( p = .02). No adverse events related to the intervention were reported. Conclusions: Rehabilitation training slippers may reduce falls in older adults.

The effectiveness of emotional freedom techniques (EFT) on depression of postmenopausal women: a randomized controlled trial

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Asieh Mehdipour ◽  
Parvin Abedi ◽  
Somayeh Ansari ◽  
Maryam Dastoorpoor
Keyword(s):  
Randomized Controlled Trial ◽  
Postmenopausal Women ◽  
Controlled Trial ◽  
Intervention Group ◽  
Control Group ◽  
Randomized Controlled ◽  
Moderate Depression ◽  
Before And After ◽  
The Mean ◽  
And Control

Abstract Objectives Postmenopausal women are at greater risk of depression. Depression may negatively affect the quality of life of women. An emotional freedom technique (EFT) is an evidence-based therapy combining cognitive and exposure components with acupressure. This study aimed to evaluate the effect of EFT on depression in postmenopausal women. Methods This was a randomized controlled trial in which 88 women with mild to moderate depression recruited from a menopausal clinic in Ahvaz, Iran, and randomly assigned into two groups of EFT (n=44) and control for sham therapy (n=44). Women in the EFT group received two sessions of training and asked to continue EFT for 8 weeks, one time per day. The Beck Depression Inventory (BDI2) completed by women before and after the intervention. The control group received training on sham acupressure points similar to the intervention group. Data collected using a demographic and BDI2. Women requested to complete the BDI2 before and after the intervention. The independent t-test, chi-square, and ANCOVA were used to analyze data. Results The mean depression score in the intervention group reduced from 20.93 ± 4.6 to 10.96 ± 4.38 in comparison to the control group that reduced from 19.18 ± 2.79 to 17.01 ± 6.05 after intervention (p=0.001). After the 8 week intervention, the frequency of moderate depression decreased from 56.8 to 9.35% in the intervention and from 50 to 29.5% in the control group. In total, 63.4 and 34.15% in the intervention and control groups were free of depression respectively after the intervention (p<0.001). Conclusions The results of this study showed that using EFT for 8 weeks could significantly reduce the mean score of depression in postmenopausal women. Using this method in public health centers for postmenopausal women is recommended.

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