Efeito da aplicação prévia ou adição de dessensibilizantes em géis de peróxido de hidrogênio no esmalte clareado

This in vitro study evaluated the effect of 35% hydrogen peroxide (35HP) gels with different desensitizing agents on color, microhardness and roughness of bleached enamel. Forty enamel-dentin specimens (6x6x2 mm2) were obtained from twenty human molars. After color measurement with a spectrophotometer, the specimens were randomized into four groups (n= 10): 35HPw- 35HP without desensitizing agent; 35HPCa- 35HP with calcium; 35HPK- 35HP with 0.5% potassium nitrate; 35HPTFa- 35HPw + topical application of 5% potassium nitrate and 2% sodium fluoride (TFa). Specimens were evaluated for color (∆Eab* and ∆E00), Vickers microhardness (VHN) and, superficial and volumetric roughness (Ra and Sa, µm) using a 3D non-contact profilometer before and 1-week after bleaching. Data were analyzed by ANOVA and Tukey tests (p< 0.05). Both treatment groups promoted a significant whitening effect and there was no difference between them for any color parameters evaluated. All groups reduced significantly the VHN, but the 35HPK showed a reduction significantly major than the other groups. 35HPCa and 35HP+TFa did not avoid the of Ra and Sa increasing. It can be concluded that 35HP bleaching gels with different desensitizing agents did not affect the whitening efficacy. However, all treatments decreased the microhardness, the addition of calcium into 35HP gel and the application of TFa before bleaching did not revert the enamel roughness under in vitro conditions.

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Effect of Citric Acid on Color Changes of Calcium Silicate-Based Cements an In Vitro Study

Applied Sciences ◽

10.3390/app11052339 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2339

Author(s):

Joanna Metlerska ◽

Till Dammaschke ◽

Mariusz Lipski ◽

Irini Fagogeni ◽

Anna Machoy-Mokrzyńska ◽

...

Keyword(s):

Citric Acid ◽

Calcium Silicate ◽

In Vitro Study ◽

Vitro Study ◽

Color Measurement ◽

Color Changes ◽

Naked Eye ◽

Root Canal Irrigants ◽

The Difference

The aim of the present in vitro study was to investigate the effects of 10% and 40% citric acid (CA) on the color of calcium silicate–based cements (CSCs) in comparison to the effects of common root canal irrigants. Samples of six CSCs (n = 6)—ProRoot MTA (Dentsply, Tulsa, OK, USA), Biodentine (Septodont, Saint-Maur-des-Fossés, France), MTA Plus (Avalon Biomed Inc, by Prevest Denpro Limited, Jammu, India), MTA Repair HP (Angelus, Londrina, PR, Brazil), Ortho MTA (BioMTA, Seoul, Korea), and Retro MTA (BioMTA, Seoul, Korea)—were immersed in 10% and 40% CA as well as 15% EDTA, 2% NaOCl, 2% CHX, and 0.9% NaCl for 15 min, 1 h, and 24 h. ΔE values, representing the difference between the final and baseline values of the color components, were then determined using a VITA Easyshade Compact 5.0 spectrophotometer. Naked-eye evaluation of the changes in color and structures of the materials was performed using our own scale. Upon immersion of the materials in both 10% and 40% CA, there were statistically significant differences between spectrophotometric color measurement results for all CSCs (P < 0.05). However, CA does not cause dark discoloration, observable with the naked eye, of any of the materials, such as NaOCl and CHX. Significant statistical differences were also found between all CSCs in terms of submersion duration (P < 0.05). CA, which could be an alternative to EDTA use, caused greater CSCs discoloration and changed some of their structures. Unless required by the therapeutic procedure, clinicians should pay attention to the fact that the irrigant may affect the CSCs discoloration and minimize the contact time of irrigant with CSCs.

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Hydroxyl Safflower Yellow Pigment A (HSYA) Improves Vascular Endothelial Injury Induced by Lipopolysaccharide In Vitro Study

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2021.2596 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1792-1798

Author(s):

Li Yan ◽

Ge Jingping ◽

Yin Yuanyuan ◽

Li Xiaomei ◽

Zhao Boxiang ◽

...

Keyword(s):

Cell Proliferation ◽

In Vitro Study ◽

Treated Group ◽

Yellow Pigment ◽

Endothelial Injury ◽

Vitro Study ◽

Vascular Endothelial ◽

Treatment Groups ◽

Dose Dependent

Aim: This research was to investigate the effects and mechanisms of HSYA in vascular endothelial injury by vitro study. Methods: Dividing HUVECs as Normal Control (NC), Model (LPS treated) group, HSYA-L, HSYA-M and HSYA-H groups. Cells in the HSYA treatment groups were treated with LPS, followed by 40 mg/ml, 80 mg/ml, and 120 mg/ml HSYA intervention (HSYA-L, HSYA-M, and HSYA -H groups), respectively. Measuring the cell proliferation, apoptosis, relative proteins and mRNA (TLR4, MyD88 and NF-κB(p65)) expressions by MTT, Flow cytometry, WB and RT-qPCR assay. Using cellular immunofluorescence to evaluate NF-κB(p65) nuclear volume of difference groups. Results: With HSYA supplement, the cell proliferation rates were significantly up-regulation with cell apoptosis significantly down-regulation with TLR4 relatived mRNA and proteins and NF-κB(p65) nuclear significantly depressed with dose-dependent (P <0.05, respectively). Conclusion: HSYA improved vascular endothelial injury induced by LPS via TLR4 pathway In Vitro.

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Fluoride Concentration in SDF Commercial Products and Their Bioavailability with Demineralized Dentine

Brazilian Dental Journal ◽

10.1590/0103-6440202003669 ◽

2020 ◽

Vol 31 (3) ◽

pp. 257-263

Author(s):

Aline Laignier Soares-Yoshikawa ◽

Jaime Aparecido Cury ◽

Cínthia Pereira Machado Tabchoury

Keyword(s):

Fluoride Concentration ◽

In Vitro Study ◽

Test Strip ◽

T Test ◽

The Other ◽

Alkaline Ph ◽

Commercial Products ◽

Silver Diamine Fluoride ◽

Direct Technique

Abstract The aim of this in vitro study was to determine the fluoride concentration in silver diamine fluoride (SDF) products and their bioavailability with demineralized dentine. The products evaluated (expected fluoride concentrations) were: I: Saforide 38% (45,283 ppm F); II: Advantage Arrest 38.3 to 43.2% (45,283 to 51,013 ppm F); III: Ancárie 12% (14,100 ppm F); IV: Ancárie 30% (35,400 ppm F), V: Cariestop 12% (14,100 ppm F) and VI: Cariestop 30% (35,400 ppm F). The fluoride concentration was evaluated using an ion-specific electrode (ISE) by direct technique, which was confirmed after microdiffusion. The pH of the products was determined with a pH test strip. For the bioavailability test, demineralized dentine slabs were treated with one of the products for 1 min. Loosely (CaF2-like) and firmly-bound fluoride (FAp) were determined. The fluoride concentration found in the products (mean±SD; ppm F) by the ISE direct technique was: I:53,491±554; II:57,249±1,851; III:4,814±268; IV:5,726±43; V:10,145±468; VI:11,858±575; these values were confirmed after microdiffusion (t-test; p>0.05) and disagree with the declared by the manufacturers. The pH of Ancárie 12 and 30% was 6.0 and 4.5, respectively, in disagreement with the alkaline pH expected for SDF solution and found in the other products evaluated. There was no correlation between either CaF2-like (r=0.221; p=0.337) or FAp (r=-0.144; p=0.830) formed in demineralized dentine and fluoride concentration found in the products. The problems of pH and fluoride concentration found in available professional commercial SDF products suggest that they are not under sanitary surveillance.

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An In-Vitro Investigation into the Cement Pressurization Achieved During Insertion of Four Different Femoral Stems

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/095441105x34400 ◽

2005 ◽

Vol 219 (6) ◽

pp. 407-413 ◽

Cited By ~ 5

Author(s):

C Gozzard ◽

S Gheduzzi ◽

A W Miles ◽

I D Learmonth

Keyword(s):

Revision Surgery ◽

In Vitro Study ◽

The Other ◽

Stem Volume ◽

Factors Associated ◽

In Vitro Investigation ◽

Femoral Stems ◽

Stem Shape ◽

Distal Stem

Adequate cement pressurization during stem insertion improves the interdigitation of cement into bone. This increases the strength of the cement-bone interface, thus contributing to the reduction of the incidence of aseptic loosening, the commonest cause of revision surgery. This in-vitro study compared the cement pressurization achieved during insertion of four different stems of equivalent sizes: the Elite Plus (DePuy, UK), C-Stem (DePuy, UK), Exeter (Stryker, USA), and CPS-Plus (Plus Orthopedics, Switzerland). The maximum pressures attained at the time of stem insertion were recorded at proximal, mid and distal stem levels. The Elite Plus generated significantly higher distal pressures than the other stems. The CPS-Plus generated significantly greater proximal cement pressures than the Elite Plus, C-Stem, and Exeter prostheses. The triple taper of the C-Stem increased the cement pressurization medial to the stem. The stem shape and the presence or absence of a proximal stem centralizer affect cement pressurization. The presence of a proximal stem centralizer, a large stem volume, and a lateral-medial taper are all factors associated with increased cement pressurization during stem insertion.

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Influence of two different desensitizers on the shear bond strength of two newly introduced bonding agents following the total etch strategy: an in vitro study

RGUHS Journal of Dental Sciences ◽

10.26715/rjds.12_1_5 ◽

2020 ◽

Vol 12 (1) ◽

pp. 3-10

Author(s):

Dr. Alok Pandey Pandey ◽

Dr. Shibani Shetty ◽

Dr. Jayalakshmi K B ◽

Dr. PrasannalathaNadig ◽

Dr. Sujatha I ◽

...

Keyword(s):

Bond Strength ◽

Testing Machine ◽

In Vitro Study ◽

Bonding Agents ◽

Group 4 ◽

Multiple Comparison Test ◽

Desensitizing Agents ◽

Group 3 ◽

Machine Analysis

Objective: Evaluate the shear bond strengths of two different dentin bonding agents following the pretreatment of dentine with two different desensitizing agents. Materials and methods: 60 premolar samples were grounded to expose the dentine. The teeth were categorized into three major groups. Each major group was subdivided into 2 subgroups of 10 samples each. Groups 1&2 involved no pretreatment with desensitizer prior to the bonding agents application. Groups 3&4 were pretreated with Gluma desensitizing agent prior to the use of All bond Universal as self-etching modality in group 3 and One Coat 7.0 in group 4. Groups 5&6 involved pretreatment with MS Coat One desensitizer and use of All bond Universal and One Coat7.0 bonding agents respectively. Shear bond testing of the samples were then evaluated by the universal testing machine. Analysis of the data was done using One-way ANOVA and pair-wise comparison was performed using Tukey’s multiple comparison test. Results: Control groups in which no pretreatment was done with any desensitizing agent had the highest bond strength when compared to the experimental groups. Among the desensitizers, significantly higher bond strength was shown by Gluma than MS Coat One. Conclusion: Gluma with One Coat 7.0 can be used to decrease the post-operative sensitivity without compromising bond strength.

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Inhibition of Demineralization at Restoration Margins of Z100 and Tetric EvoCeram Bulk Fill in Dentin and Enamel

Bioengineering ◽

10.3390/bioengineering6020036 ◽

2019 ◽

Vol 6 (2) ◽

pp. 36

Author(s):

Cristina Leon-Pineda ◽

Kevin Donly

Keyword(s):

Light Microscopy ◽

Polarized Light ◽

In Vitro Study ◽

The Other ◽

Solution Ph ◽

Class V ◽

The Mean ◽

Student’S T ◽

Student’S T Test

Recurrent caries is still considered the main reason restorations need to be replaced. There are different materials available now that promise to reduce the possibility of recurrent caries by releasing fluoride and inhibiting restoration marginal caries. The purpose of this in vitro study was to evaluate the demineralization inhibition potential of a non-fluoride-releasing resin (Z100TM 3M, St. Paul, MN, USA) and a glass containing resin-based composite (Tetric EvoCeram Bulk Fill, Ivoclar/Vivadent AG, Schaan, Liechtenstein), which contains fluoride. Class V preparations were placed on 22 premolars; the gingival margin was below the cementoenamel junction and the occlusal margin was placed above the cemento-enamel junction. Ten teeth were randomly selected to be restored with Z100 while the other 10 were restored with Tetric EvoCeram Bulk Fill. Both groups were restored following manufacturer’s instructions. All teeth had an acid resistant varnish placed within one millimeter of the preparation margins. Both groups were placed in artificial caries challenge solution (pH 4.4). At the end of the 4 days; 100 µm buccolingual sections were obtained for each tooth; these were photographed under polarized light microscopy and the demineralized areas adjacent to the restorations were measured and quantified. The mean (±S.D.) area (µm2) of demineralization from the occlusal margin (enamel) and dentin margin were: Z100 2781.889 ± 1045.213; 3960.455 ± 705.964 and for Tetric EvoCeram Bulk Fill 1541.545 ± 1167.027; 3027.600 ± 512.078. Student’s t-test indicated that there was significantly less enamel and dentin demineralization adjacent to Tetric EvoCeram Bulk Fill compared to Z100; there was significantly less demineralization in enamel compared to dentin in both Tetric EvoCeral Bulk Fill and Z100. Tetric EvoCeram Bulk Fill performed better inhibiting demineralization at restoration margins when compared to Z100 and provided better demineralization inhibition in enamel than cementum/dentin.

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Effect of Different Intermediary Bases on Microleakage of a Restorative Material in Class II Box Cavities of Primary Teeth

The International Journal of Artificial Organs ◽

10.5301/ijao.5000566 ◽

2017 ◽

Vol 40 (2) ◽

pp. 82-87 ◽

Cited By ~ 1

Author(s):

Faika Y. Abdelmegid ◽

Fouad S. Salama ◽

Waleed M. Al-Mutairi ◽

Saud K. Al-Mutairi ◽

Sultan O. Baghazal

Keyword(s):

Primary Teeth ◽

In Vitro Study ◽

Class Ii ◽

Positive Control ◽

Negative Control ◽

The Other ◽

Control Groups ◽

Significant Difference ◽

The Mean

Introduction The aim of this in vitro study was to assess and compare the effect of different intermediary bases on microleakage between tooth and a nanocomposite interface in Class II box cavities in primary teeth. Methods Standard Class II box cavities were prepared in 52 primary molars and randomly divided into 9 groups according to the intermediary base used (Multicore Flow, Fuji II LC, SDR, Smart Dentin Replacement, and Biodentine). All specimens were subjected to thermocycling and prepared for microleakage testing and evaluation. Results There was significant difference in the mean ranks of microleakage between the 9 groups, which was observed in the gingival side (p<0.0001) and the occlusal side (p<0.0001). The mean ranks microleakage was significantly higher with experimental SDR, experimental Multicore Flow, and positive control materials when compared with the other 6 groups. The microleakage mean ranks were statistically significantly lower in experimental Fuji II LC, experimental Biodentine, and all negative control groups when compared with the other 3 groups. Conclusions Microleakage is affected by the application of intermediate material. Experimental Biodentine and Fuji II LC showed the lowest microleakage while experimental SDR and experimental Multicore Flow showed the highest microleakage.

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Effects of External Bleaching on Indentation and Abrasion Characteristics of Human Enamel in vitro

Journal of Dental Research ◽

10.1177/00220345920710061201 ◽

1992 ◽

Vol 71 (6) ◽

pp. 1340-1344 ◽

Cited By ~ 114

Author(s):

R.R. Seghi ◽

I. Denry

Keyword(s):

Fracture Toughness ◽

Surface Hardness ◽

In Vitro Study ◽

Organic Matrix ◽

Chemical Action ◽

Apparent Fracture Toughness ◽

Human Enamel ◽

Dental Hard Tissues ◽

Bleaching Gels

The application of home-bleaching procedures as a means of lightening multiple teeth has become increasingly popular. Very few studies, however, have determined the effect of this treatment upon dental hard tissues. This in vitro study evaluated the effects of a 10% carbamide peroxide gel on the apparent fracture toughness, hardness, and abrasion characteristics of human enamel. The apparent fracture toughness of enamel was reduced by about 30% after bleaching for a period of 12 hours with no significant change in surface hardness. Enamel treated with the bleaching gels also exhibited a small but significant decrease in abrasion resistance. This behavior was most likely due to an alteration of the organic matrix of enamel under the chemical action of hydrogen peroxide. Further investigation of the clinical significance of this process is needed.

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Effect of a carbamide peroxide bleaching gel containing calcium or fluoride on human enamel surface microhardness

Brazilian Dental Journal ◽

10.1590/s0103-64402005000200003 ◽

2005 ◽

Vol 16 (2) ◽

pp. 103-106 ◽

Cited By ~ 33

Author(s):

Rogério de Oliveira ◽

Adriana Franco Paes Leme ◽

Marcelo Giannini

Keyword(s):

Artificial Saliva ◽

In Vitro Study ◽

Enamel Surface ◽

Control Group ◽

Carbamide Peroxide ◽

Surface Microhardness ◽

Treatment Groups ◽

Peroxide Bleaching ◽

Human Enamel

This in vitro study evaluated the surface microhardness of human enamel submitted to bleaching with 10% carbamide peroxide (CP) containing calcium or fluoride. Ninety-eight dental blocks (5 x 5 mm²) with polished enamel surfaces were randomly assigned to 7 treatment groups (n=14), as follows: without bleaching and storage in artificial saliva (control); 10% CP; 10% CP + 0.05% calcium; 10% CP + 0.1% calcium; 10% CP + 0.2% calcium; 10% CP + 0.2% fluoride; and 10% CP + 0.5% fluoride. During 14 days, enamel surfaces were daily exposed to a 6-h bleaching regimen followed by storage in artificial saliva. Surface microhardness was measured before (baseline), during (7th day), immediately after bleaching (14th day) and 1 week post bleaching. Data were analyzed by two-way ANOVA and Tukey's test (p<0.05). All treatments reduced SM significantly during the bleaching cycle (7th day), immediately after bleaching (14th day) and 1 week post bleaching, compared to baseline and to the unbleached control group. In conclusion, in spite of the addition of calcium and fluoride, all bleaching treatments affected the enamel surface microhardness.

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