scholarly journals Near-Surface Studies of the Changes to the Structure and Mechanical Properties of Human Enamel under the Action of Fluoride Varnish Containing CPP–ACP Compound

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 765 ◽  
Author(s):  
Izabela Świetlicka ◽  
Damian Kuc ◽  
Michał Świetlicki ◽  
Marta Arczewska ◽  
Siemowit Muszyński ◽  
...  

Changes to the features of the enamel surface submitted to induced demineralisation and subsequent remineralisation were studied. The in vitro examination was conducted on polished slices of human molar teeth, divided in four groups: the untreated control (n = 20), challenged by a demineralisation with orthophosphoric acid (H3PO4) (n = 20), and challenged by a demineralisation following remineralisation with fluoride (F) varnish containing casein phosphopeptides (CPP) and amorphous calcium phosphate (ACP) compounds (n = 20). The specimens’ enamel surfaces were subjected to analysis of structure, molecular arrangement, mechanical features, chemical composition, and crystalline organization of apatite crystals. Specimens treated with acid showed a significant decrease in crystallinity, calcium, and phosphorus levels as well as mechanical parameters, with an increase in enamel surface roughness and degree of carbonates when compared to the control group. Treatment with fluoride CPP–ACP varnish provided great improvements in enamel arrangement, as the destroyed hydroxyapatite structure was largely rebuilt and the resulting enamel surface was characterised by greater regularity, higher molecular and structural organisation, and a smoother surface compared to the demineralised one. In conclusion, this in vitro study showed that fluoride CPP–ACP varnish, by improving enamel hardness and initiating the deposition of a new crystal layer, can be an effective remineralising agent for the treatment of damaged enamel.

2005 ◽  
Vol 16 (2) ◽  
pp. 103-106 ◽  
Author(s):  
Rogério de Oliveira ◽  
Adriana Franco Paes Leme ◽  
Marcelo Giannini

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.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2458 ◽  
Author(s):  
Bruna Raquel Zancopé ◽  
Vanessa B. Dainezi ◽  
Marinês Nobre-dos-Santos ◽  
Sillas Duarte ◽  
Vanessa Pardi ◽  
...  

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.


2012 ◽  
Vol 13 (5) ◽  
pp. 584-589 ◽  
Author(s):  
Sukran Bolay ◽  
Filiz Yalcin Cakir ◽  
Sevil Gurgan

ABSTRACT Aim The aim of this in vitro study was to evaluate the surface roughness and hardness of both unbleached and bleached (opalescence; 10% carbamide peroxide) human enamel brushed with water (without dentifrice), fluoride abrasive dentifrice (Colgate Total) and whitening dentifrice (Natural White). Materials and methods Human enamel samples were obtained from third molars and randomly divided into five groups (n = 8): G1—Control (brushed with water without dentifrice), G2—Colgate Total (fluoride abrasive dentifrice), G3—Natural White (whitening dentifrice), G4—Opalescence (10% carbamide peroxide) and then brushed with Colgate Total, G5— Opalescence (10% carbamide peroxide) and then brushed with Natural White. Bleaching regimen was applied according to manufacturers’ instructions. The brushing process was performed with a modified Nyffenegger's brushing machine. Surface roughness was analyzed with a profilometer. Microhardness testing was performed with a Brinell hardness tester. Results Results were statistically analyzed by Kruskal-Wallis, one-way ANOVA analysis and Mann-Whitney U, Wilcoxon matched-pairs signed-ranks tests. There were significant differences in surface roughness values for all groups, which showed an increase in roughness (p < 0.05). When the bleaching treatment combined with brushing with whitening dentifrice was performed (G5), there was a significant decrease in hardness values (p < 0.05). The other groups (G1, G2, G3, G4) showed no significant hardness differences (p > 0.05). Conclusion It was concluded that toothbrushing procedures increased the enamel surface roughness, and that bleaching regimen performed with cleaning treatment, through brushing with whitening dentifrice decreased hardness values. Clinical significance When applied together, bleaching and cleaning treatments may alter the enamel surface roughness and hardness values. How to cite this article Bolay S, Cakir FY, Gurgan S. Effects of Toothbrushing with Fluoride Abrasive and Whitening Dentifrices on Both Unbleached and Bleached Human Enamel Surface in Terms of Roughness and Hardness: An in vitro Study. J Contemp Dent Pract 2012;13(5):584-589.


2016 ◽  
Author(s):  
Bruna Raquel Zancope ◽  
Vanessa B Dainezi ◽  
Marinês Nobre-dos-Santos ◽  
Sillas Duarte, Jr ◽  
Vanessa Pardi ◽  
...  

Background. CO2 laser has been used to morphologically and chemically modify the dental enamel surface as well as to turn it more resistant to demineralization. Despite a variety of experiments demonstrating the inhibitory effect of CO2 laser 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 CO2 laser (λ = 10.6 µM). Methods. For this in vitro study, it was employed 96 specimens of bovine enamel, which were divided into 2 groups (n = 48): 1) Control-non-irradiated surface and 2) Irradiated enamel surface. Biofilms were grown on the enamel specimens by 1, 3 and 5 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 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. Results. The mean of log CFU/ml obtained for the 1-day biofilm evaluation showed that there is statistical difference between the experimental groups. When biofilms were exposed to CO2 laser, CFU/mL and CFU/ Dry Weight in 3 day was reduced significantly compared with control group. The difference in the genes expression (gtfB and gbpB) and polysaccharides was not statically significant. Contact angle was increased relative to control when the surface was irradiated with CO2 laser. Similar morphology was also visible with both treatments, however irradiated group revealed evidence of melting and fusion in the specimens. Conclusion. In conclusion CO2 laser irradiation modify the energy surface and disrupt the initial biofilm formation.


2017 ◽  
Vol 22 (4) ◽  
pp. 53-60 ◽  
Author(s):  
Nasrin Farhadian ◽  
Loghman Rezaei-Soufi ◽  
Seyed Farzad Jamalian ◽  
Maryam Farhadian ◽  
Shahrzad Tamasoki ◽  
...  

ABSTRACT Introduction: Many patients seeking orthodontic treatment already have incipient enamel lesions and should be placed under preventive treatments. The aim of this in vitro study was to evaluate the effect of CPP-ACP paste and CO2 laser irradiation on demineralized enamel microhardness and shear bond strength of orthodontic brackets. Methods: Eighty caries-free human premolars were subjected to a demineralization challenge using Streptococcus mutans. After demineralization, the samples were randomly divided into five equal experimental groups: Group 1 (control), the brackets were bonded without any surface treatment; Group 2, the enamel surfaces were treated with CPP-ACP paste for 4 minutes before bonding; Group 3, the teeth were irradiated with CO2 laser beams at a wavelength of 10.6 µm for 20 seconds. The samples in Groups 4 and 5 were treated with CO2 laser either before or through CPP-ACP application. SEM photomicrographs of a tooth from each group were taken to observe the enamel surface. The brackets were bonded to the buccal enamel using a conventional method. Shear bond strength of brackets and ARI scores were measured. Vickers microhardness was measured on the non-bonded enamel surface. Data were analyzed with ANOVA and Tukey test at the p< 0.05 level. Results: The mean shear bond strength and microhardness of the laser group were higher than those in the control group and this difference was statistically significant (p< 0.05). All groups showed a higher percentage of ARI score 4. Conclusion: CO2 laser at a wavelength of 10.6 µm significantly increased demineralized enamel microhardness and enhanced bonding to demineralized enamel.


2007 ◽  
Vol 1 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Seema Hallikerimath ◽  
Ravi V Shirahatti ◽  
L Nagesh

ABSTRACT Prevention of initiation and interruption in progression of early lesions are the desirable modes of caries management. Fluoride dentifrices and casein phosphopeptides are known to inhibit demineralization and enhance remineralization. The present study was conducted with the objective to investigate the effects of fluoridated dentifrice, non-fluoridated dentifrice and casein phosphopeptide amorphous calcium phosphate paste on enamel caries formation and lesion depth progression.228 tooth sections derived from extracted human permanent molars.were used The study was carried out in 3 phases where in each phase the enamel sections were treated for 14 days twice a day for 3 minutes with respective agents, followed by acid demineralization using 0.05 M acetic acid resulting in lesions. The depths of the lesions were measured using stereomicroscope. The mean lesion depths of three test groups were compared with each other as well as with control group at the end of each phase. Comparison of mean lesion depths of different groups was carried out using analysis of variance (ANOVA) and student's unpaired-t-test. The fluoridated dentifrice group had significantly lesser mean lesion depth than control group in all the three phases (P<0.05). In second phase, non-fluoridated dentifrice and CPP-ACP paste groups had significantly lesser mean lesion depths than control groups (P<0.05). The study demonstrated that twice a day application of fluoridated dentifrice provides substantial protective effect against lesion formation and lesion depth progression. The study could not demonstrate any additional ability of CPP-ACP paste in reducing lesions depth progression and effect was similar to non-fluoridated dentifrice group.


2003 ◽  
Vol 17 (4) ◽  
pp. 342-348 ◽  
Author(s):  
Claudia Cia Worschech ◽  
José Augusto Rodrigues ◽  
Luis Roberto Marcondes Martins ◽  
Gláucia Maria Bovi Ambrosano

The aim of this in vitro study was to evaluate the surface roughness of human enamel bleached with 35% carbamide peroxide at different times and submitted to different superficial cleaning treatments: G1 - not brushed; G2 - brushed with fluoride abrasive dentifrice; G3 - brushed with a non-fluoride abrasive dentifrice; G4 - brushed without dentifrice. Sixty fragments of human molar teeth with 4 x 4 mm were obtained using a diamond disc. The specimens were polished with sandpaper and abrasive pastes. A perfilometer was used to measure roughness average (Ra) values of the initial surface roughness and at each 7-day-interval after the beginning of treatment. The bleaching was performed on the surface of the fragments for 1 hour a week, and the surface cleaning treatment for 3 minutes daily. The samples were stored in individual receptacles with artificial saliva. Analysis of variance and the Tukey test revealed significant differences in surface roughness values for G2 and G3, which showed an increase in roughness over time; G1 and G4 showed no significant roughness differences. The bleaching with 35% carbamide peroxide did not alter the enamel surface roughness, but when the bleaching treatment was performed combined with brushing with abrasive dentifrices, there was a significant increase in roughness values.


2012 ◽  
Vol 13 (6) ◽  
pp. 756-759 ◽  
Author(s):  
Roshan Uthappa ◽  
ML Suprith ◽  
Shreetha Bhandary ◽  
Sumit Dash

ABSTRACT The purpose of the study was to compare two different commercial bleaching agents, Opalescence with Colgate Platinum, and 30% phosphoric acid used as aggressive agent on the morphology of human enamel. Materials and methods Ten freshly extracted, noncarious, human maxillary central incisors extracted for periodontal reasons were used in this study. The labial surface of the disinfected teeth were polished using a polishing paste with the help of rubber cup and a slow speed handpiece. Each tooth was sectioned at cement-enamel junction and the crown was separated into four specimens, all taken from labial surface. Group 1 was treated with Colgate Platinum for 7 hours, group 2 with Opalescence for 7 hours, group 3 was treated with 30% phosphoric acid for 30 seconds and group 4 was untreated and used as control. After the treatment period, the specimens were washed with normal saline and stored in sterile bottle and sealed. Photomicrographs obtained from the scanning electron microscopy (SEM) after surface treatments were examined for no alteration, slight alteration, moderate alteration and severe alterations. Results The specimens treated with commercial bleaching agents revealed no enamel surface morphologic alterations compared to control group. The specimen treated with phosphoric acid showed severe alterations. Conclusion Ten percent carbamide peroxide evaluated in this study does not etch tooth enamel or alter enamel surface morphology as do conventional etching techniques. Clinical relevance Carbamine peroxide is a safe and effective tooth whitening agent even when used for extended period of time. The enamel surface remains smooth which reduces caries due to plaque collection. How to cite this article Uthappa R, Suprith ML, Bhandary S, Dash S. A Comparative Study of Different Bleaching Agents on the Morphology of Human Enamel: An in vitro SEM Study. J Contemp Dent Pract 2012;13(6):756-759.


2018 ◽  
Vol 1 (1) ◽  
pp. 59
Author(s):  
Aditya Kartika Noviyanti Putri ◽  
Thalca Hamid ◽  
Ari Triwardhani

Background: Debonding aims to remove orthodontic appliances from the patient's teeth and cleanse all residual adhesive material on the surface of the tooth to restore surface conditions such as before orthodontic treatment. Damage may occur after debonding process. Removal of the remaining adhesive material has a major effect on the enamel surface conditions, the researcher wants to know the effect of cleaning adhesive material using Tungsten carbide 12 flute burs, Arkansas stone bur on the enamel surface Purpose: To determine the effect of cleaning the remaining adhesive material using Tungsten carbide 12 flute burs and Arkansas stone bur Against the Surface of the Enamel. Method: This study was experimental laboratory (in vitro study) with 4 groups division, first control group was tooth before bracket was installed, group 2 was done debonding without cleaning of residual adhesive, group 3 was done adhesive cleansing with Arkansas stone and group 4 was done adhesive cleaning with tungsten carbide 12-flutted Result: Showing that the use of 12-flutted tungsten carbide was able to clean enamel surfaces with the most delicate results and did not cause cracks or cracks on enamel surface Conclusions: The best method to clean the remaining adhesive is using 12-flutted tungsten carbide bur using contra angle high speed and with adequate water flow and sprays to prevent increasing of temperature that damage dental pup.


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