scholarly journals Influence of Thymoquinone Exposure on the Micro-Hardness of Dental Enamel: An In Vitro Study

2019 ◽  
Vol 13 (03) ◽  
pp. 318-322 ◽  
Author(s):  
Imran Farooq ◽  
Saqib Ali ◽  
Intisar Ahmad Siddiqui ◽  
Khalifa S. Al-Khalifa ◽  
Mohammed Al-Hariri
Keyword(s):  
Artificial Saliva ◽  
Dental Enamel ◽  
In Vitro Study ◽  
Rank Test ◽  
Control Group ◽  
Micro Hardness ◽  
Signed Rank Test ◽  
The Mean ◽  
Experimental Group

Abstract Objective The aim of this study was to assess changes in micro-hardness level of enamel after it was exposed to thymoquinone (TQ). Materials and Methods Sixteen enamel blocks were prepared and divided into two groups (each group received eight blocks, n = 8); Gp 1 (control): enamel blocks kept in 100 mL artificial saliva (AS) for 24 hours and Gp 2: enamel blocks kept in a mixture of TQ powder (1 g) and AS (100 mL) for 24 hours. Post-immersion they were subjected to simulated brushing with each sample receiving 8,000 linear strokes. For brushing, 3 mL of AS and TQ oil was used for groups 1 and 2, respectively. Enamel surfaces were analyzed for changes in values of surface micro-hardness (pre-immersion, post-immersion, and post-brushing) by obtaining Vickers hardness number (VHN). Results The present study indicated improvement in micro-hardness levels for both groups although experimental group showed more enhancement. The mean baseline VHN for control group was 498.6, 500.4 for post-immersion, and 503.5 for post-brushing. The mean baseline VHN for experimental group was 448.7, 531 for post-immersion, and 610.3 for post-brushing. Statistically significant differences (p < 0.05) were observed when post-brushing VHN values of both groups were compared and also within the experimental group when post-brushing values were compared with baseline values. Statistical Analysis Wilcoxon signed-rank test was applied for the evaluation of pre- and post-exposure hardness values. Level of significance was ≤0.05. Conclusion The exposure of enamel to TQ led to an improvement in its micro-hardness levels. Further studies are required to understand the mechanism of action of TQ on human tissues.

scholarly journals Evaluation of The Erosive Potential of Soft Drinks

2007 ◽  
Vol 01 (01) ◽  
pp. 010-013 ◽  
Author(s):  
Sílvia Helena de Carvalho Sales-Peres ◽  
Ana Carolina Magalhães ◽  
Maria Aparecida de Andrade Moreira Machado ◽  
Marília Afonso Rabelo Buzalaf
Keyword(s):  
Artificial Saliva ◽  
Dental Enamel ◽  
In Vitro Study ◽  
Glass Electrode ◽  
Buffering Capacity ◽  
Soft Drinks ◽  
Enamel Erosion ◽  
The Mean ◽  
Bovine Enamel

ABSTRACTObjectives: This in vitro study evaluated the capability of different soft drinks (Coca-Cola® -C, Coca- Cola Light® -CL, Guaraná® -G, Pepsi Twist® -P and Sprite Light® -SL) to erode dental enamel, relating the percentage of superficial microhardness change (%SMHC) to concentrations of fluoride and phosphate, buffering capacity and pH of these drinks.Methods: The soft drinks were evaluated in respect to concentration of phosphate and fluoride spectrophotometrically using Fiske, Subarrow method and by specific electrode (Orion 9609), respectively. The pH and the buffering capacity were determined by glass electrode and by estimating of the volume of NaOH necessary to change the pH of the drink in one unit, respectively. One hundred specimens of bovine enamel were randomly assigned to 5 groups of 20 each. They were exposed to 4 cycles of demineralisation in the beverage and remineralisation in artificial saliva. The softening of enamel was evaluated by %SMHC.Results: The mean %SMHC was:C=77.27%, CL= 72.45%, SL=78.43%, G=66.65% and P=67.95%. Comparing the %SMHC promoted by 5 soft drinks, SL = C > CL > P = G (P<.05). There was not significant correlation between %SMHC and the other variables tested for the five drinks (P>>.05)Conclusions: The five soft drinks caused surface softening of enamel (erosion). In respect to the chemical variables tested, despite not statistically significant, the pH seems to have more influence on the erosive potential of these drinks. (Eur J Dent 2007;1:10-13)

Effect of Zinc Sulfate on Human Primary Enamel Microhardness: An in vitro Study

2012 ◽  
Vol 36 (4) ◽  
pp. 369-371 ◽  
Author(s):  
M Mirkarimi ◽  
M Bargrizan ◽  
S Eskandarion ◽  
M Shahsavari
Keyword(s):  
Zinc Sulfate ◽  
Artificial Saliva ◽  
In Vitro Study ◽  
Hardness Test ◽  
Knoop Hardness ◽  
Control Group ◽  
Expected Time ◽  
Rich Solution ◽  
The Mean

Objective: The aim of this study was to assess the effect of zinc sulfate on microhardness of human primary enamel. Method: Sixteen sound primary molars were sectioned mesiodistally. For each sample one of the sections was randomly immersed in artificial saliva (Biotene,USA) and the other was immersed in artificial saliva which was charged with 10 mg/5mL concentration of zinc sulfate supplement (Razak Company, Iran) daily. After 24 days (the expected time to use up one 120-mL bottle) the surface microhardness of enamel was measured by knoop hardness test (KH) with Knoop diamond under a 50-gram load for 10 seconds. Results: The mean (± SD) microhardness values (KHV) for the tested groups were 320 ± 49.45 and 357 ± 36.35, respectively. There were statistically significant differences between the groups as exhibited by independent t-test (P=0.023). Conclusion: Primary teeth immersed in a zinc sulfate rich solution for 24 days showed higher microhardness values in comparison with the control group.

scholarly journals Evaluation of fluoride releasing and recharging of orthodontic adhesive resins: An in vitro study.

2020 ◽  
Vol 3 (2) ◽  
pp. 126-134
Author(s):  
Sava Bakhtyar ◽  
Bayan Hassan
Keyword(s):  
Color Change ◽  
In Vitro Study ◽  
Rank Test ◽  
Common Side Effect ◽  
Control Group ◽  
Fluoride Release ◽  
Adhesive Resin ◽  
Fixed Appliance ◽  
Signed Rank Test

Background and objective: Development of white spot lesions to be a well-recognized and common side effect of orthodontic fixed appliance, in spite of vast improvement in preventive dental techniques and procedures. The aim of this study is to determine and compare amount of fluoride releasing and recharging of orthodontic adhesive resins. Materials and methods: 12 specimens for fluoride releasing and recharging were used for each tested materials, materials tested for fluoride releasing were Transbond plus color change and Resilience (fluoridated ortho-adhesive resin). Fluoride releasing was estimated daily for 14 days, then weekly up to 28 days, then at day 42, 70 days. For fluoride recharging in addition to above materials Transbond XT (non- fluoridated ortho-adhesive resin) were used as a control group. The 12 specimens of each material were divided into two equal subgroups to simulate two different methods of fluoride application, namely, brushing with fluoride-containing toothpaste and after the topical application of fluoride gel. Fluoride releasing was measured at days 1,2,3,7 for gel application while for brushing group releasing of fluoride was measured at 7 days. Results: Mann Whitney test, Kruskal Wallis test and Wilcoxon signed rank test were used for statistical analysis. During tested period all materials showed statically different capacity to release and uptake fluoride. Transbond plus color change was highest ability for fluoride releasing and recharging when compared to others materials. Conclusion: Transbond plus color change and Resilience, showed fluoride release in distal de-ionized water. For fluoride recharging Transbond plus color change had more ability for re-charging than two other materials. Keywords: Fluoride release, fluoride recharge, ortho-adhesive resin.

scholarly journals Potential of different fluoride gels to prevent erosive tooth wear caused by gastroesophageal reflux

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Philipp Körner ◽  
Luca Georgis ◽  
Daniel B. Wiedemeier ◽  
Thomas Attin ◽  
Florian J. Wegehaupt
Keyword(s):  
Gastroesophageal Reflux ◽  
Artificial Saliva ◽  
In Vitro Study ◽  
Tooth Wear ◽  
Control Group ◽  
Erosive Tooth Wear ◽  
Custom Made ◽  
Post Hoc ◽  
Bovine Enamel

Abstract Background This in-vitro-study aimed to evaluate the potential of different fluoride gels to prevent gastroesophageal reflux induced erosive tooth wear. Methods Surface baseline profiles of a total of 50 bovine enamel specimens [randomly assigned to five groups (G1–5)] were recorded. All specimens were positioned in a custom made artificial oral cavity and perfused with artificial saliva (0.5 ml/min). Reflux was simulated 11 times a day during 12 h by adding HCl (pH 3.0) for 30 s (flow rate 2 ml/min). During the remaining 12 h (overnight), specimens were stored in artificial saliva and brushed twice a day (morning and evening) with a toothbrush and toothpaste slurry (15 brushing strokes). While specimens in the control group (G1) did not receive any further treatment, specimens in G2–5 were coated with different fluoride gels [Elmex Gelée (G2); Paro Amin Fluor Gelée (G3); Paro Fluor Gelée Natriumfluorid (G4); Sensodyne ProSchmelz Fluorid Gelée (G5)] in the evening for 30 s. After 20 days, surface profiles were recorded again and enamel loss was determined by comparing them with the baseline profiles. The results were statistically analysed using one-way analysis of variance (ANOVA) followed by Tukey`s HSD post-hoc test. Results The overall highest mean wear of enamel (9.88 ± 1.73 µm) was observed in the control group (G1), where no fluoride gel was applied. It was significantly higher (p < 0.001) compared to all other groups. G2 (5.03 ± 1.43 µm), G3 (5.47 ± 0.63 µm, p = 0.918) and G4 (5.14 ± 0.82 µm, p > 0.999) showed the overall best protection from hydrochloric acid induced erosion. Enamel wear in G5 (6.64 ± 0.86 µm) was significantly higher compared to G2 (p = 0.028) and G4 (p = 0.047). Conclusions After 20 days of daily application, all investigated fluoride gels are able to significantly reduce gastroesophageal reflux induced loss of enamel.

scholarly journals An in vitro comparison of the force decay generated by different commercially available elastomeric chains and NiTi closed coil springs

2007 ◽  
Vol 21 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Ana Cristina Soares Santos ◽  
André Tortamano ◽  
Sandra Regina Frazatto Naccarato ◽  
Gladys Cristina Dominguez-Rodriguez ◽  
Julio Wilson Vigorito
Keyword(s):  
Artificial Saliva ◽  
Testing Machine ◽  
In Vitro Study ◽  
Original Length ◽  
Force Decay ◽  
Decay Pattern ◽  
The Mean ◽  
Initial Force ◽  
Elastomeric Chains

This in vitro study was designed to compare the forces generated by commercially available elastomeric chains and NiTi closed coil springs, and to determine their force decay pattern. Forty elastomeric chains and forty NiTi closed coil springs were divided into 4 groups according to the following manufacturers: (1) Morelli®, (2) Abzil®, (3) TP Orthodontics® and (4) American Orthodontics®. The specimens were extended to twice their original length and stored in artificial saliva at 37°C. Initial force was measured by means of an Instron universal testing machine and then at 1, 4, 7, 14, 21, and 28 days. The results revealed that the elastomeric chains delivered a mean initial force of 347 g for Morelli®, 351 g for American Orthodontics®, 402 g for Abzil®, and 404 g for TP Orthodontics®. The NiTi closed coil springs generated a mean initial force of 196 g for American Orthodontics®, 208 g for TP Orthodontics®, 216 g for Abzil®, and 223 g for Morelli®. The mean percentage of force decay observed after 28 days for the elastomeric chains was 37.4% for TP Orthodontics®, 48.1% for American Orthodontics®, 65.4% for Morelli®, and 71.6% for Abzil®. After 28 days, the NiTi closed coil springs presented a mean percentage of force decay of 22.6% for American Orthodontics®, 29.8% for Abzil®, 30.6% for Morelli®, and 45.8% for TP Orthodontics®. At the end of the study, significant differences were observed between the elastomeric chains and the NiTi closed coil springs. The results indicated that the studied NiTi closed coil springs are more adequate for dental movement than the elastomeric chains.

scholarly journals Effect of topical fluoride on microshear bond strength of primary enamel to composite, microhardness of enamel and its surface morphology: An in vitro study

2019 ◽  
Vol 13 (4) ◽  
pp. 305-310
Author(s):  
Mina Biria ◽  
Sajedeh Namaei Ghasemi ◽  
Seyedeh Mahsa Sheikh-Al-Eslamian ◽  
Narges Panahandeh
Keyword(s):  
Bond Strength ◽  
Artificial Saliva ◽  
Morphological Characteristics ◽  
In Vitro Study ◽  
Vitro Study ◽  
Control Group ◽  
Modes Of Failure ◽  
Group 3 ◽  
Microshear Bond Strength

Background. This in vitro study aimed to evaluate the microshear bond strength (μSBS), microhardness and morphological characteristics of primary enamel after treating with sodium fluoride (NaF) and acidulated phosphate fluoride (APF). Methods. Forty-eight primary canines were cut into mesial and distal sections and assigned to five groups randomly: group 1 (immersed in saliva as a control), group 2 (treated with NAF and immersed in saliva for 30 minutes), group 3 (treated with APF and immersed in saliva for 30 minutes), group 4 (treated with NAF and immersed in saliva for 10 days), and group 5 (treated with APF and immersed in saliva for 10 days). Composite resin (Filtek Z250) was bonded on the specimens (n=15) for measuring the μSBS. After storage in 37°C artificial saliva for 24 hours, µSBS and Vickers hardness tests (10 readings) were performed. The data were analyzed using one-way ANOVA and Kolmogorov-Smirnov, Levene’s and Tukey HSD tests (P<0.05). Morphological analysis of enamel and modes of failure were carried out under a scanning electron microscope (SEM) on two remaining specimens. Results. Significant differences in μSBS were only noted between groups 2 and 4 (P=0.024). Group 3 showed a significant decrease in hardness after storage in artificial saliva (P<0.001), with a significantly lower hardness than the other groups (P<0.001). The SEM observations showed irregular particles in groups 3 and 5; uniform, smooth and thin coats were seen in groups 2 and 4. Conclusion. Fluoride therapy with NaF and APF gels prior to restorative treatments had no adverse effects on the microshear bond strength.

scholarly journals Effects of CO2laser irradiation on matrix-rich biofilm development formation–an in vitro study

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2458 ◽  
Author(s):  
Bruna Raquel Zancopé ◽  
Vanessa B. Dainezi ◽  
Marinês Nobre-dos-Santos ◽  
Sillas Duarte ◽  
Vanessa Pardi ◽  
...  
Keyword(s):  
Contact Angle ◽  
Biofilm Formation ◽  
Dental Enamel ◽  
In Vitro Study ◽  
Dry Weight ◽  
Vitro Study ◽  
Enamel Surface ◽  
Control Group ◽  
Biofilm Development

BackgroundA carbon dioxide (CO2) laser has been used to morphologically and chemically modify the dental enamel surface as well as to make it more resistant to demineralization. Despite a variety of experiments demonstrating the inhibitory effect of a CO2laser in reduce enamel demineralization, little is known about the effect of surface irradiated on bacterial growth. Thus, this in vitro study was preformed to evaluate the biofilm formation on enamel previously irradiated with a CO2laser (λ = 10.6 µM).MethodsFor this in vitro study, 96 specimens of bovine enamel were employed, which were divided into two groups (n = 48): 1) Control-non-irradiated surface and 2) Irradiated enamel surface. Biofilms were grown on the enamel specimens by one, three and five days under intermittent cariogenic condition in the irradiated and non-irradiated surface. In each assessment time, the biofilm were evaluated by dry weigh, counting the number of viable colonies and, in fifth day, were evaluated by polysaccharides analysis, quantitative real time Polymerase Chain Reaction (PCR) as well as by contact angle. In addition, the morphology of biofilms was characterized by fluorescence microscopy and field emission scanning electron microscopy (FESEM). Initially, the assumptions of equal variances and normal distribution of errors were conferred and the results are analyzed statistically by t-test and Mann Whitney test.ResultsThe mean of log CFU/mL obtained for the one-day biofilm evaluation showed that there is statistical difference between the experimental groups. When biofilms were exposed to the CO2laser, CFU/mL and CFU/dry weight in three day was reduced significantly compared with control group. The difference in the genes expression (Glucosyltransferases (gtfB) and Glucan-binding protein (gbpB)) and polysaccharides was not statically significant. Contact angle was increased relative to control when the surface was irradiated with the CO2laser. Similar morphology was also visible with both treatments; however, the irradiated group revealed evidence of melting and fusion in the specimens.ConclusionIn conclusion, CO2laser irradiation modifies the energy surface and disrupts the initial biofilm formation.

scholarly journals Enamel Surface Roughness after Lingual Bracket Debonding: An In Vitro Study

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4196
Author(s):  
Martina Eichenberger ◽  
Anna Iliadi ◽  
Despina Koletsi ◽  
George Eliades ◽  
Carlalberta Verna ◽  
...  
Keyword(s):  
Surface Roughness ◽  
In Vitro Study ◽  
Rank Test ◽  
Roughness Parameters ◽  
Signed Rank ◽  
Fine Diamond ◽  
Before And After ◽  
Signed Rank Test ◽  
Lingual Brackets

The aim of the present study was to quantitatively assess changes in enamel roughness parameters before and after lingual bracket debonding. The lingual surface of 25 sound premolars extracted for orthodontic reasons was studied by 3D optical interferometric profilometry before and after debonding of lingual brackets following enamel finishing (with fine diamond) and polishing (with 12- and 20-fluted carbide burs). The roughness parameters tested were the amplitude parameters Sa and Sz, the hybrid parameter Sdr, and the functional parameters Sc and Sv. The parameter differences (after debonding-reference) were calculated, and statistical analysis was performed via a Wilcoxon signed-rank test. Statistically significantly higher values were observed in all the surface roughness parameters of enamel surfaces after finishing and polishing, with the mostly affected parameter being the Sdr. Under the conditions of the present study, the finishing and polishing instruments used after debonding of lingual noncustomized brackets created a surface texture rougher than the control in all the tested roughness parameters.

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

2005 ◽  
Vol 16 (2) ◽  
pp. 103-106 ◽  
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.

scholarly journals Effects of a periodized functional strength training program (FST) on Functional Movement Screen (FMS) in physical education students

2020 ◽  
Vol 24 (3) ◽  
pp. 162-167
Author(s):  
Michał Sawczyn
Keyword(s):  
Physical Education ◽  
Strength Training ◽  
Statistical Significance ◽  
Rank Test ◽  
Training Intervention ◽  
Control Group ◽  
Before And After ◽  
Signed Rank Test ◽  
The Difference ◽  
Experimental Group

Background and Study Aim: To examine the effects of periodized functional strength training (FST) on FMS scores of sport university students with higher risk of injury. Material and Methods: Thirty three  participants (age 21.6±1.3 years, height 177.8±6.9 m, mass 80.4±7.7 kg) with FMS total score ≤ 14 were selected from eighty two volunteered students of University of Physical Education and Sport in Gdańsk and randomly assigned to experimental group (n=16) and control group (n=17). The FMS test was conducted one week before and one week after the 12 week training intervention. The experimental group participated in FST program through 12 weeks. The control group did not engaged in any additional physical activity than planned in their course of study. The  collected  data  were  analysed  using Statistica 13.3 pl (StatSoft Inc). Wilcoxon signed rank test was used to establish the statistical significance of the difference between FMS total scores within each group and Mann Whitney U test between groups before and after the 12 week training intervention. Results: 45 % of volunteers in the first FMS testing showed total scores ≤14. The experimental group that participated in FST program changed significantly FMS total scores after 12 weeks (p<0.05). There were also significant differences in FMS total score between groups after the experiment (p<0.05). Conclusions: There is a need for injury prevention programs for students of University of Physical Education and Sport in Gdańsk. It is clear from this study that FST is effective in improving FMS total score in students with cut off score ≤14.

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