Influence of Simulated Pulpal Pressure on Efficacy of Bleaching Gels

ABSTRACT Aim The aim of this study was to investigate the influence of simulated pulpal pressure on efficacy of bleaching gels. Materials and methods Cylindrical enamel-dentin specimens from bovine teeth (3 mm diameter, enamel and dentin layer each 1 mm thick) were divided into 4 groups, according to the bleaching treatment: negative control (non-bleached), bleached with 10% carbamide peroxide (CP), bleached with 7.5% hydrogen peroxide (HP) and bleached with 35% hydrogen peroxide. Ten percent CP gel was applied for 8 h/day and 7.5% HP for 1 h/day, during 14 days. For 35% HP treatment, two sessions of 45 minutes each were employed. In intermediate periods specimens were stored in artificial saliva. Experimental groups (n = 19) were subdivided according to the simulation of pulpal pressure (25 mm Hg) during bleaching treatment. Initial color measurement and after bleaching treatment were assessed by spectrophotometry, using CIE L*a*b* system. The data were statistically analyzed by ANOVA and Dunnett's posthoc tests (p < 0.05). Results There was significant difference of ∆E for all experimental groups compared to negative control group, according to Dunnett's test (p < 0.0001). There were no significant difference for total color variation (∆E) among experimental groups (p > 0.05). Conclusion It was concluded that all bleaching gels showed bleaching efficacy compared to non-bleached group and that the simulated pulpal pressure did not influence the bleaching outcomes of the tested gels. Clinical significance Although numerous in vitro studies investigating the efficacy of bleaching agents have been performed, they do not properly simulate the pulpal pressure. In order to make these studies closer to clinical conditions, it is important to reproduce these conditions in laboratory, so the results can be more reliable. This in vitro study was performed under simulated pulpal pressure, aiming to investigate its influence on dental bleaching outcomes. How to cite this article Borges AB, Batista GR, Arantes PT, Wiegand A, Attin T, Torres CRG. Influence of Simulated Pulpal Pressure on Efficacy of Bleaching Gels. J Contemp Dent Pract 2014;15(4):407-412.

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Effects of a bleaching agent with calcium on bovine enamel

European Journal of Dentistry ◽

10.4103/1305-7456.137634 ◽

2014 ◽

Vol 08 (03) ◽

pp. 320-325 ◽

Cited By ~ 9

Author(s):

Larissa Alexandrino ◽

Yasmin Gomes ◽

Eliane Alves ◽

Hilton Costi ◽

Hervé Rogez ◽

...

Keyword(s):

Artificial Saliva ◽

In Vitro Study ◽

Negative Control ◽

Double Blind ◽

Tristimulus Colorimetry ◽

Mean Values ◽

Significant Difference ◽

Bovine Enamel ◽

Bleaching Treatment

ABSTRACT Objective: This in vitro study analyzed the effects of a bleaching treatment containing 35% hydrogen peroxide (HP) with or without calcium on bovine enamel, using the Knoop hardness number (KHN), tristimulus colorimetry (TC), and scanning electron microscopy. Materials and Methods: Forty-five specimens were randomly divided into groups (n = 5), which included artificial saliva (negative control [NC]), 35% HP (positive control [PC]), and 35% HP Blue Calcium (HP Blue). The specimens were subjected to three bleaching sessions. During the sessions, the specimens were immersed in artificial saliva at 37°C. Before and after bleaching, KHN tests were conducted using a force of 25 gf for 5 s. TC was performed using the CIE-L*a*b* system and readouts were obtained at the following 4 time points: Before the bleaching treatment; after the first session, the second session, and the third session. The specimens were dehydrated and coated with gold, and the photomicrographs were analyzed in a double-blind manner with a LEO microscope. Results: Using one-way analysis of variance and Tukey's test (P < 0.05), a statistically significant difference was identified between the initial and final mean KHNs of the NC and PC groups, while the initial and final mean KHNs were not significantly different in the HP Blue group. The final mean values of ⋄E, ⋄L, and ⋄b of the PC and HP Blue groups were significantly higher than the initial values (P < 0.01 for both). The photomicrographs revealed no differences among the groups. Conclusions: Therefore, treatment with HP Blue prevented changes in the KHN without reducing the efficacy of bleaching.

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Whitening mouthwash containing hydrogen peroxide decreases enamel microhardness in vitro.

Brazilian Journal of Oral Sciences ◽

10.20396/bjos.v16i0.8650504 ◽

2017 ◽

Vol 16 ◽

pp. 1-9 ◽

Cited By ~ 1

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.

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Influence of Hydrogen Peroxide Bleaching Gels on Color, Opacity, and Fluorescence of Composite Resins

Operative Dentistry ◽

10.2341/11-189-l ◽

2012 ◽

Vol 37 (5) ◽

pp. 526-531 ◽

Cited By ~ 10

Author(s):

CRG Torres ◽

CF Ribeiro ◽

E Bresciani ◽

AB Borges

Keyword(s):

Hydrogen Peroxide ◽

Composite Resin ◽

Color Change ◽

Composite Resins ◽

Control Group ◽

Peroxide Bleaching ◽

Color Changes ◽

Tukey Test ◽

Bleaching Gels ◽

Bleaching Treatment

SUMMARY The aim of the present study was to evaluate the effect of 20% and 35% hydrogen peroxide bleaching gels on the color, opacity, and fluorescence of composite resins. Seven composite resin brands were tested and 30 specimens, 3-mm in diameter and 2-mm thick, of each material were fabricated, for a total of 210 specimens. The specimens of each tested material were divided into three subgroups (n=10) according to the bleaching therapy tested: 20% hydrogen peroxide gel, 35% hydroxide peroxide gel, and the control group. The baseline color, opacity, and fluorescence were assessed by spectrophotometry. Four 30-minute bleaching gel applications, two hours in total, were performed. The control group did not receive bleaching treatment and was stored in deionized water. Final assessments were performed, and data were analyzed by two-way analysis of variance and Tukey tests (p<0.05). Color changes were significant for different tested bleaching therapies (p<0.0001), with the greatest color change observed for 35% hydrogen peroxide gel. No difference in opacity was detected for all analyzed parameters. Fluorescence changes were influenced by composite resin brand (p<0.0001) and bleaching therapy (p=0.0016) used. No significant differences in fluorescence between different bleaching gel concentrations were detected by Tukey test. The greatest fluorescence alteration was detected on the brand Z350. It was concluded that 35% hydrogen peroxide bleaching gel generated the greatest color change among all evaluated materials. No statistical opacity changes were detected for all tested variables, and significant fluorescence changes were dependent on the material and bleaching therapy, regardless of the gel concentration.

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THE EFFECTIVENESS OF SOURSOP LEAF EXTRACT AGAINST GROWTH OF AGGREGATIBACTER ACTINOMYCETEMCOMITANS ATCC® 6514™ IN VITRO

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i12.28435 ◽

2018 ◽

Vol 11 (12) ◽

pp. 411

Author(s):

Ameta Primasari ◽

Minasari Nasution ◽

Nurul Hidayati Arbi ◽

Dini Permata Sari ◽

Mohammad Basyuni

Keyword(s):

Leaf Extract ◽

Brain Heart Infusion ◽

Aggregatibacter Actinomycetemcomitans ◽

Negative Control ◽

Plate Count ◽

Control Group ◽

Control Group Design ◽

Significant Difference ◽

Mueller Hinton Agar

Objective: The objective of this study was to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) antibacterial power of soursop leaf extract on Aggregatibacter actinomycetemcomitans (Aa) ATCC® 6514™ growth.Methods: This study was experimental laboratory with post-test only control group design and consists of 8 treatment groups that were soursop leaf extract group with concentration 50%, 25%, 12.5%, 6.25%, 3.125%, and 1.5625% as well as negative control groups were brain heart infusion broth (BHIB) media and chlorhexidine as positive controls. Each treatment was done 3 repetitions. Testing the effectiveness of soursop leaf extract using dilution methods on BHIB and subculture media on Mueller Hinton Agar (MHA) media. The number of Aa ATCC® 6514 ™ colonies was calculated manually using the total plate count method on the MHA media. Data were analyzed using Kruskal–Wallis test (p<0.05) followed by least significance different (LSD) test to see the significant mean difference between treatment groups.Results: Concentration of MIC from soursop leaf extract on Aa ATCC® 6514™ growth was 1.5625% and MBC was 6.25%. LSD assay results showed significant difference effect (p<0.05) Aa ATCC® 6514™ from each treatment group.Conclusion: Soursop leaf extract has antibacterial effectivity against Aa ATCC® 6514 ™.

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In vitro Comparative Evaluation of the Fracture Resistance of Simulated Immature Teeth reinforced with Different Apical Barriers and Obturation Combination

World Journal of Dentistry ◽

10.5005/jp-journals-10015-1377 ◽

2016 ◽

Vol 7 (3) ◽

pp. 113-118

Author(s):

Neveen A Shaheen ◽

Nahla G El-Din El-Helbawy

Keyword(s):

Fracture Resistance ◽

Comparative Evaluation ◽

Negative Control ◽

Control Group ◽

Root Canals ◽

Immature Teeth ◽

Gutta Percha ◽

Group I ◽

Significant Difference

ABSTRACT Aim This study aimed to assess and compare the fracture resistance of simulated immature teeth reinforced with Biodentine (BD) and mineral trioxide aggregate (MTA) as apical barriers and two root canal backfilling combination (gutta-percha/AH26, MetaSeal). Materials and methods A total of 70 extracted human maxillary incisors were randomly divided into seven groups (n = 10). The positive control group was not instrumented. For the other groups, coronal access was made and root canals were instrumented using the ProTaper, up to F5 followed by six Peeso reamers which were allowed to pass 1 mm beyond the apex to size 6 (1.7 mm) to simulate immature teeth. The apical 4 mm of their root canals was filled with either MTA or BD apical barrier, then backfilled with gutta-percha/AH26 or MetaSeal obturation combination. The negative control group was left unfilled. Composite resin was used to restore the coronal access cavities. The maximum load for fracture of each tooth was recorded utilizing a universal testing machine. Data were analyzed using two-way analysis of variance. Results The noninstrumented group I had the highest fracture resistance and differed significantly (p < 0.05) from the negative control groups. On the contrary, no significant difference was found between BD and MTA groups, regardless of the backfilling combination (p > 0.05). Conclusion There was no difference between MTA and BD apical barriers and the backfilling combination regarding their resistance to root fracture. How to cite this article Shaheen NA, El-Din El-Helbawy NG. In vitro Comparative Evaluation of the Fracture Resistance of Simulated Immature Teeth reinforced with Different Apical Barriers and Obturation Combination. World J Dent 2016;7(3):113-118.

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Bleaching Gels Containing Calcium and Fluoride: Effect on Enamel Erosion Susceptibility

International Journal of Dentistry ◽

10.1155/2012/347848 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 16

Author(s):

Alessandra B. Borges ◽

Carlos R. G. Torres ◽

Paulo A. B. de Souza ◽

Taciana M. F. Caneppele ◽

Luciana F. T. F. Santos ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Calcium Gluconate ◽

Artificial Saliva ◽

Bleaching Agent ◽

Enamel Erosion ◽

Agent Control ◽

Bovine Enamel ◽

Enamel Wear ◽

Bleaching Gels

Thisin vitrostudy evaluated the effect of 35% hydrogen peroxide (HP) bleaching gel modified or not by the addition of calcium and fluoride on enamel susceptibility to erosion. Bovine enamel samples (3 mm in diameter) were divided into four groups (n=15) according to the bleaching agent: control—without bleaching (C); 35% hydrogen peroxide (HP); 35% HP with the addition of 2% calcium gluconate (HP + Ca); 35% HP with the addition of 0.6% sodium fluoride (HP + F). The bleaching gels were applied on the enamel surface for 40 min, and the specimens were subjected to erosive challenge with Sprite Zero and remineralization with artificial saliva for 5 days. Enamel wear was assessed using profilometry. The data were analyzed by ANOVA/ Tukey’s test (P<0.05). There were significant differences among the groups (P=0.009). The most enamel wear was seen for C (3.37±0.80 μm), followed by HP (2.89±0.98 μm) and HP + F (2.72±0.64 μm). HP + Ca (2.31±0.92 μm) was the only group able to significantly reduce enamel erosion compared to C. The application of HP bleaching agent did not increase the enamel susceptibility to erosion. However, the addition of calcium gluconate to the HP gel resulted in reduced susceptibility of the enamel to erosion.

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Effect of Different Finishing and Polishing Methods for Color Stability of the E-Max Dental Ceramics: In vitro Study

Bioscience Biotechnology Research Communications ◽

10.21786/bbrc/14.4.21 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1508-1513

Author(s):

Ibraheem F Alshiddi

Keyword(s):

Surface Brightness ◽

Color Stability ◽

Color Measurement ◽

Control Group ◽

Group 4 ◽

Significant Difference ◽

Group 3 ◽

Group 2 ◽

Group 1

In order to assess the influence of finishing and polishing on the surface brightness and color stability of the ceramic veneer, fifty specimens were fabricated with 10 mm diameter and 2 mm thickness using IPS E-Max Ceramic. After glazing, 10 specimens were untouched as control group, and the other 40 specimens were abraded using 125µm diamond bur to create surface roughness. Forty specimens were divided into four groups (n=10), in group 1: specimens were finished using diamond point, in group 2 specimens’ surface was polished with a polishing kit, Group 3: Each specimen surface was polished with the polishing kit as in protocol 2 and was polished a polishing past and group 4 Each specimen was glazed by heating at 621℃ for 3 minutes followed by a temperature increase of 83℃/min up to 918℃ for 30 seconds. Color measurement was performed using spectrophotometer. Color stability data were analyzed using two-way ANOVA and Tukey’s HSD test (α=0.05). For Ra values, paired-samples t-tests were used to analyze the data and compare groups. The change in L and E showed a significant difference among the study groups; (group 1, group 2, group 3 and group 4) with respect to three variables L, a and b. A significant difference was noted when compared each group with the control; however, only group 2 showed a significant difference from group 4; the remaining groups demonstrated similar findings for all three variables. The study displayed a significant impact of the finishing and polishing technique on the surface brightness and color stability of ceramic restoration. However, it was evident that combination of two or three polishing techniques which includes polish kit and glaze enhances the surface finish and adds color stability by alternating the yellow – blue axis (increase in b) and red- green axis (decrease in a).

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The effect of alcohol-containing mouthwash and alcohol-free mouthwash towards the power chains force decay

Padjadjaran Journal of Dentistry ◽

10.24198/pjd.vol29no3.14476 ◽

2017 ◽

Vol 29 (3) ◽

Author(s):

Willem Santana ◽

Bergman Thahar ◽

Endah Mardiati ◽

Jono Salim

Keyword(s):

Orthodontic Treatment ◽

Artificial Saliva ◽

Chlorhexidine Gluconate ◽

Comparative Approach ◽

Control Group ◽

Force Decay ◽

Significant Difference ◽

The Common ◽

Common Device

Introduction: Power chains is the common device used in fixed orthodontic treatment. Force decay in power chains is a problem that can affect the teeth movement due to a continuous force cannot be maintained. Force decay in power chain can be affected by the use of alcohol-containing mouthwash or alcohol-free mouthwash. The objective of this study was to determine the effect of alcoholic-containing mouthwash, alcohol-free mouthwash, and artificial saliva towards the power chains force decay. Methods: This research was an experimental analytic laboratory in-vitro with the comparative approach. The sample in this study were 40 power chain, short A (SA); 40 power chain, short B (SB); 40 power chain, long A (LA); and 40 power chain, long B (LB), which divided into 5 groups that were consecutively exposed to the artificial saliva as control group; Minosep® with 0.1% of chlorhexidine gluconate; Listerine® with 0% of alcohol; Hexadol® with 9% of alcohol; and Listerine® with 26.9% of alcohol. The measurement of force decay was performed with digital force gauge on day 0, 1, 14, and 28. The statistical analysis was done by using the Wilcoxon and Mann-Whitney tests. Result: There was a significant difference (p<0.05) between the force decay of power chain that exposed to the alcohol-containing mouthwash, alcohol-free mouthwash, and the artificial saliva. Conclusion: The force decay level of power chain that exposed to an alcohol-containing mouthwash was higher compared to the force decay level of power chain that exposed to an alcohol-free mouthwash and an artificial saliva.

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Evaluation of the apical microleakage of MTA Fillapex, AH26, and Endofill sealers

Brazilian Dental Science ◽

10.14295/bds.2020.v23i3.1895 ◽

2020 ◽

Vol 23 (3) ◽

Author(s):

Saeedeh Galledar ◽

Robab Farhang ◽

Malek Abazari ◽

Parisa Negahdar

Keyword(s):

Root Canal ◽

Test Group ◽

In Vitro Study ◽

Negative Control ◽

Vitro Study ◽

Control Group ◽

Dye Penetration ◽

Gutta Percha ◽

Significant Difference

Objective: Proper apical seal plays an important role in the success of root canal treatment. The most common cause of failure of root canal therapy is known as the lack of adequate apical seal. The aim of this in vitro study was to compare the apical microleakage of MTA Fillapex, , and Endofill sealers using dye penetration method. Material and Methods: In this in vitro study, 72 single-rooted extracted human teeth were selected. The teeth were randomly divided into three experimental groups of 20 and two positive and negative control groups of 6. The canals were prepared by step-back technique and then filled with gutta-percha and one of the sealers mentioned. In the positive control group, the canals were filled with gutta-percha without sealer, and in the negative control group, the canals were prepared but not filled. The teeth were immersed in 2% methylene blue dye for 72 hours. The teeth were then cut longitudinally and the level of dye penetration was measured under a stereomicroscope. Data were analyzed by SPSS ver. 19 software, ANOVA and Bonferroni post-hoc tests. Results: The mean level of dye penetration in the Endofill test group was significantly higher than that in the and MTA Fillapex test groups. While, the observed difference between and MTA Fillapex groups was not statistically significant (p<0.05). Conclusion: The results of this study showed that and MTA Fillapex sealers did not show any significant difference in apical seal properties. However, their sealing strength was significantly greater than Endofill sealer.KeywordsAH26 sealer; Endofill; MTA Fillapex; Microleakag

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Spectrophotometric Analysis Evaluating Apical Microleakage in Retrograde Filling using GIC, MTA and Biodentine: An in-vitro study

10.21203/rs.2.15368/v3 ◽

2020 ◽

Author(s):

Manisha Nepal ◽

Snigdha Shubham ◽

Rupam Tripathi ◽

Jwolan Khadka ◽

Deepa Kunwar ◽

...

Keyword(s):

Negative Control Group ◽

Positive Control ◽

Negative Control ◽

Control Group ◽

Filling Materials ◽

Diamond Bur ◽

Retrograde Filling ◽

Significant Difference ◽

Supernatant Solution

Abstract Background The present study compares the apical microleakage of three different root-end filling materials in which the retrograde cavity is prepared by two different burs. Methods Eighty extracted single rooted maxillary and mandibular premolars were taken. Root canal treatment was completed. Apical 3 mm of all the teeth were resected with diamond disk. The tooth were divided into four groups with two subgroups for each group containing 10 tooth (N= 10) as: Group IA (Negative Control and IB (Positive Control); Group IIA and IIB: Prepared with round carbide bur and round diamond bur respectively, filled with GIC; Group IIIA and IIIB: Prepared with round carbide bur and round diamond bur respectively, filled with MTA; Group IVA and IVB: Prepared with round carbide bur and round diamond bur, filled with Biodentine. After applying two coats of nail varnish leaving apical 3 mm (except for negative control group) all teeth were immersed in 2% methylene blue for 3 days and again in 65% nitric acid for next 3 days for extraction of dye. The obtained solution was then transferred to eppendorf tube and centrifuged in microcentrifuges at 14,000 revolution per minutes (RPM) for 5 minutes. Optical density or absorbance of the supernatant solution was measured with UV spectrophotometer at 550 nm. Results The absorbance of the supernatant solution after dye extraction is decreasing in the order of positive control> GIC> MTA> Biodentine> negative control group. The significant difference was observed between GIC and MTA (p=0.0001) and GIC and Biodentine (p=0.0001) with two different burs but statistically non-significant difference was observed between MTA and Biodentine with Carbide bur (p=0.127) and Diamond bur (p=0.496) respectively. Conclusions Within the limitations of the present study, it can be concluded that Biodentine and MTA showed less microleakage as compared to GIC. There is no significant difference between mean microleakage of MTA and Biodentine. However, the mean OD of the Biodentine was least of all evaluated materials. Preparation of the root-end using round carbide bur as well as round diamond burs showed comparable microleakage for all three filling materials.

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