Demineralized Enamel Surface Research Articles

Biomimetic chitosan against bioinspired nanohydroxyapatite for repairing enamel surfaces

In this study, chitosan was employed as a novel biomimetic mineralization model to repair damaged enamel to compare its performance with that of bioinspired zinc-doped nanohydroxyapatite. Fifty human premolar tooth slices were prepared, and artificial caries lesions were induced to produce demineralized enamel surfaces. The etched slices were randomly divided into two groups: a chitosan-hydrogel-treated group and a zinc-doped nanohydroxyapatite-treated group. In vitro assessment using energy-dispersive X-ray analysis, X-ray diffraction analysis and scanning electron microscopy was conducted at the baseline, demineralization and remineralization stages. Baseline results were matched with those for normal enamel; a marked reduction in the calcium (Ca)/phosphorus (P) ratio to 1·12 and the lack of the characteristic hydroxyapatite diffraction peaks were detected for demineralized enamel. The remineralization stage revealed evident recovery of the mineral contents (the calcium/phosphorus ratio was 1·61 for the chitosan-treated group and 1·58 for the bioinspired-nanohydroxyapatite-treated one), with apparent distinctive X-ray diffraction patterns of hydroxyapatite in both groups. Scanning electron microscopic analysis showed the absence of etched enamel porosity, with the formation of a newly formed rod-like apatite layer, similar to natural enamel, which extended over the treated enamel surfaces of both groups. Chitosan hydrogel is recommended as a biomimetic mineralization smart system for repairing demineralized carious enamel.

Effect of resin infiltration application on early proximal caries lesions in vitro

Background/purposeResin infiltration (RI) material ICON is used in treating early proximal caries lesions, as it depends on a micro–invasive infiltration technology. This in vitro study aimed to evaluate the effect of ICON resin infiltration (RI) on early proximal caries by comparing surface roughness and hardness before and after treatment with RI using atomic force microscopy (AFM), automated microhardness testing system (AMHTS), and scanning electron microscopy (SEM) in vitro. Materials and methodsTwenty seven premolars extracted for orthodontic reasons were sectioned buccolingually, creating 54 specimens. Each specimen was immersed in demineralizing solution to induce caries. Only teeth with “International Caries Detection and Assessment System” codes 1 and 2 were selected. The specimens were divided randomly into either AFM, AMHTS or SEM groups, which examined demineralized enamel before and after treatment with ICON. ResultsThe mean average surface roughness and root mean square roughness values of demineralized enamel treated with ICON were significantly higher than untreated lesions (P < 0.001). The mean Vickers hardness values for demineralized enamel treated with ICON was significantly higher than untreated lesions (P < 0.001). SEM showed irregular, pitted and rough demineralized enamel surface with destruction of enamel rods and dissolution of enamel crystals. After ICON application, the surface showed complete blockage of enamel rods with RI and irregular, rough uneven topography. ConclusionRI application on proximal incipient caries increased surface roughness and hardness significantly.

The role of salivary contents and modern technologies in the remineralization of dental enamel: a narrative review

Human enamel once formed cannot be biologically repaired or replaced. Saliva has a significant role in remineralization of dental enamel. It not only has a buffering capacity to neutralize the oral cavity's low pH generated after acidic encounters, but also acts as a carrier of essential ions, such as fluoride, calcium and phosphate, which have a positive role in enamel's remineralization. This review discusses how salivary contents, like proteins and enzymes, have a natural role in enamel's mineralization. In addition, the presence of ions, such as fluoride, calcium and phosphate, in saliva further enhances its capability to remineralize the demineralized enamel surface. The review further examines modern innovative technologies, based on biomimetic regeneration systems, including dentin phosphoproteins, aspartate-serine-serine, recombinant porcine amelogenin, leucine-rich amelogenin peptide and nano-hydroxyapatite, that promote enamel remineralization. Fluoride boosters like calcium phosphates, polyphosphates, and certain natural products can also play an important role in enamel remineralization.

The role of salivary contents and modern technologies in the remineralization of dental enamel: a review

Human enamel once formed cannot be biologically repaired or replaced. Saliva has a significant role in remineralization of dental enamel. It not only has a buffering capacity to neutralize the oral cavity’s low pH generated after acidic encounters, but also acts as a carrier of essential ions, such as fluoride, calcium and phosphate, which have a positive role in enamel’s remineralization. This review discusses how salivary contents, like proteins and enzymes, have a natural role in enamel’s mineralization. In addition, the presence of ions, such as fluoride, calcium and phosphate, in saliva further enhances its capability to remineralize the demineralized enamel surface. The review further examines modern innovative technologies, based on biomimetic regeneration systems, including dentin phosphoproteins, aspartate-serine-serine, recombinant porcine amelogenin, leucine-rich amelogenin peptide and nano-hydroxyapatite, that promote enamel remineralization. Fluoride boosters like calcium phosphates, polyphosphates, and certain natural products can also play an important role in enamel remineralization.

Evaluation of diode laser application on chemical analysis and surface microhardness of white spots enamel lesions with two remineralizing agents.

BackgroundTo investigate the effect of diode laser application and two commercial remineralizing agents on the remineralization and surface microhardness of white spot enamel lesions. Material and MethodsSixty specimens were prepared then equally divided into six groups (n=10/group), according to the diode laser and the two commercial remineralizing agents applied to demineralized enamel surfaces (APF gel and sodium fluoride NaF mousse) with or without diode Laser application as follows; Group A; control, Group B; diode Laser application, Group C; APF gel application, Group D; NaF mousse application, Group E; APF gel application + diode Laser, Group F; NaF mousse application+ diode Laser. Then the teeth were investigated for their Ca, P & F ions content and surface microhardness. One-way ANOVA followed by Tukey’s (HSD) post hoc test were used for statistical analysis. ResultsCa ion wt% showed no statistically significant difference between tested groups, with the highest mean value recorded with Group C. P ion wt%, showed a statistically significant difference between Groups A and C, and the highest mean value was recorded for Group A. The highest F ion wt% was recorded for Group C, while the lowest was recorded for both A and B groups. The highest significant microhardness mean values was recorded for Group E, while the lowest was recorded for Group A. ConclusionsDiode Laser treatment of the demineralized enamel surface had a positive influence on the chemistry and surface microhardness and it may represent a promising adjunct for enamel surface remineralization. Key words:Diode Laser application, chemical analysis, surface microhardness, remineralizing agents, white spot lesions.

Comparative Evaluation of the Effects of Silver Diamine Fluoride (Commercial and Lab Prepared) versus Nano silver fluoride on Demineralized Human Enamel Surfaces (In Vitro Study)

Background: - To evaluate and compare the effects of Silver diamine fluoride (commercial and lab prepared) versus nano silver fluoride on demineralized human enamel surfaces. Materials and methods: - A total 20 Extracted premolars for orthodontic reasons were collected from the Outpatient Clinic of surgical Department, Faculty of Dentistry, Suez Canal University. Each premolar was sectioned buccolingually into two halves, to obtain (40) specimens. These halves were randomly allocated into 5 groups according to different treatment modalities. Group I included 8 specimens were left untreated (negative control), Group II included 8 specimens were treated with demineralizing solution, Group III included 8 specimens were treated by Silver diamine fluoride (commercial form) after demineralizing solution, Group IV included 8 specimens were treated with Silver diamine fluoride (lab prepared) after demineralizing solution and Group V included 8 specimens that were treated with Nano silver fluoride after demineralizing solution. Each half was evaluated by Environmental scanning electron microscope and Energy dispersive x-ray spectroscopy .Results: There were significant differences between groups at P-value (≤0.05) for Phosphrous, Calcium and Calcium/Phosphrous ratio except (Fluoide). The lowest value for elements was recorded in group (II) followed by control group and the highest value was recorded at group (V).Conclusion: Silver Diamine Fluoride (lab made) is as efficient as commercial one in remineralizing demineralized enamel surfaces. Nano Silver Fluoride is more efficient than Silver Diamine Fluoride (lab made & commercial) on demineralized enamel surfaces.

Evaluation of the efficacy of Regenamel in the treatment of white spot lesions: an in vitro study

ABSTRACT:Objective: The aim of this study was to evaluate the efficacy of REGENAMEL® on white spot lesions (WSLs)in terms of the extent of color change and the degree of mineralization.Materials and methods: Artificial white spot lesions were induced in 40 extracted human premolars, divided into a test and a control groups. REGENAMEL® was applied to the test group according to manufacturer's instructions, while the control group received no treatment. Both groups were incubated in remineralizing solution for 90 days at 37 °C. Specimens were evaluated using VITA Easyshade advance spectrophotometer at baseline (E0), after WSLs induction (E1) and 90 days following treatment (E2).DIAGNOdent evaluation was done After WSLs induction (D1) and at the end of incubation period (D2). Results: The Data was collected and statistical analyses were done using Statistical Package for Social Sciences (SPSS).No significant difference between groups was found after formation of WSLs ΔE (T0 - T1). Meanwhile significant difference was present between the two groups when comparing the color change after 90 days (T2-T1). ΔE values were 8.2 ± 4.81 and 1.92 ± 1.21 for the test and control groups respectively. Despite the final outcome showed marked improvement when compared to the baseline readings (T2-T0) 4.94 ± 3.66, the final color of the lesions was still not matching the baseline color. For the DIAGNOdent readings, at T1 the mean value for the test group was 15.55 ± 3.81 while that of the control group was 14.95 ± 2.16. At T2, for the test group, all specimens showed significantly decreased fluorescence values towards the values of sound dental tissues with mean value of 9.9 ± 1.94. The fluorescence values for the control group at T2 showed minimal change with mean value of 13.65 ± 2.03. Conclusion: REGENAMEL® is effective in improving the color of WSLs and remineralization of demineralized enamel surface.

Novel hybrid chitosan/calcium phosphates microgels for remineralization of demineralized enamel – A model study

Dental caries remains one of the most prevalent bacteria caused diseases affecting both adults and children. It is a dynamic process which progress depends on the interplay between demineralization, caused by the bacteria produced acids from the consumption of sugars, and remineralization that takes place due to the saliva protective qualities/functions. The acids start to dissolve calcium and phosphate from the enamel (demineralization) and at the initial stage, when the tooth damage is not significant, the opposite process – the calcium and phosphate deposition (remineralization) could arrest the caries development thus making the caries a preventable disease. The development of new materials for enhancing the remineralization process is one of the main approaches of the non-invasive dentistry and also one of the main challenges of the advanced dental materials science.In the present study, hybrid chitosan/calcium phosphates microgels were developed for the first time. Their potential and effectiveness as remineralizing agent, enhancing the nucleation and growth of calcium phosphates on a model demineralized enamel surface, was revealed. The hybrid microgels formation was guided by the chitosan macromolecules which acted as a template for the calcium phosphate deposition and resulted into in situ formation of amorphous to poorly crystalline non stoichiometric hydroxyapatite. These newly developed hybrid materials have several advantages as remineralizing agent, including bio-adhesiveness, antimicrobial properties as well as continuous supply of calcium and phosphate ions to ensure the successful remineralization of the model initial caries lesions.Thus, the study reveals a simple and easy to apply remineralization procedure based on the newly developed hybrid materials that could be effectively used for arresting and enhancement of the remineralization of early-stage caries development taking advantage of the night regime of the oral cavity habits. This simple approach has been tested and proved to be effective for remineralization of initial enamel demineralization.

Evaluation of remineralization potential of casein phospho-peptide with amorphous calcium phosphate fluoride (CPP-ACPF) on demineralised enamel surfaces.

Dental caries is one of the worldwide common disease affecting both rural and urban communities. Demineralization is the loss of significant amount of minerals, especially calcium and phosphate from the tooth enamel leading to caries formation. The process of demineralization and remineralization is considered as a dynamic process, characterized by the flow of phosphate and calcium out of and back in the enamel. Therefore, the current in-vitro study was designed for evaluating the remineralization potential of casein phospho-peptide with amorphous calcium phosphate fluoride (CPP-ACPF) on the artificially demineralized enamel surfaces samples. Thirty enamel samples were subjected to artificial demineralization procedure followed by remineralization using CPP-ACPF for one week in ten samples, two weeks in next ten sample and four-week s in last ten samples. The final results were analysed using the Confocal Laser Scanning Microscopic (CLSM) and Image J software. The mean score of remineralization potential for one, two- and four-week samples was found to be 59.1064, 58.96 and 56.95 respectively. The mean gray value scores were almost similar in one, two- and four-week samples i.e., the remineralization potential does not increase or decrease significantly with increasing time. But the overall CPP-ACPF remineralization potential was high and therefore it can be used as a potential agent to prevent dental caries. The data from our current study will help to make clinical use of the agent as a potential and excellent local slow-delivery system to treat the white spot lesion in enamel.

Effects of treatment with three types of varnish remineralizing agents on the microhardness of demineralized enamel surface.

BackgroundRemineralization of incipient caries is one of the goals in dental health care ,especially in pediatric dentistry. The present study aimed at comparing the effects of MI varnish (3M (United states)) , Nano paste( FGM(Brezil) ), 5% sodium fluoride varnish) DuraphatColgate (united states) ) on remineralization of enamel lesions.Material and MethodsIn this in-vitrostudy, 60 intact human pre-molars, were randomly allocated to four groups of 15. Baseline surface microhardness in three points in the center of the polished area was measured. After two days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 under-went treatment with MI varnish, nano paste, 5% sodium fluoride varnish and then again microhardness was measured. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Bonfreni table was used.ResultsDuraphat varnish in comparison with control group, significantly increased surface microhardness and in comparison with Nano and MI paste varnish groups significant differences was shown between groups. (P< 0.05). MI paste varnish and Nano paste similary showed more increases in surface microhardness in comparison with Duraphat varnish and control groups (P≈1).ConclusionsAccording to the results of this study, all three varnishes, Duraphat , MI paste and Nano paste increase the enamel surface microhardness and remineralization of incipient caries. MI paste and Nano paste compared to Duraphat Varnish, significantly showed more increases in enamel surface microhardness but Nano paste and MI paste were almost the same. Key words:CPP-ACP, Nano varnish, fluoride varnish, microhardness, demineralization, remineralization.

Effect of Artificial Saliva, Bioactive Glass and Fluoride Varnish on Micro-hardness and Micro -shear Bond Strength of Demineralized Enamel Surface

Objectives: the aim of this study was to compare the effect of 3 different remineralizing agents on microhardness and microshear bond strength of demineralized enamel surface.Materials and methods: A total of 50 teeth were divided into five groups (10 each) that were summarized as follows: Group 1: sound unprepared teeth (base line control); Groups 2: demineralized enamel (negative control). Group 3: demineralized enamel stored in artificial saliva for one month. Group 4: demineralized enamel treated by bioactive glass (sylic powder). Group 5: demineralized enamel treated by fluoride varnish (positive control). Five samples from each group were used to test the micro-hardness and the other five samples were used to microshear bond strength.Results: A statistical significant difference was found in microhardness between the sound enamel group and both of the demineralized enamel and the fluoride varnish test groups ,meanwhile no statistically significant difference was found between sound enamel group and both of the artificial saliva test group and the Sylc powder test group. Also, there was a statistically significant difference in microshear bond strength between sound enamel and each of demineralized enamel, demineralized enamel with artificial saliva, demineralized enamel with Sylc powder and demineralized enamel with Fluoride varnish. Conclusion: The two remineralizing agents; bioactive glass and artificial saliva are capable of enhancing microhardness and micro shear bond strength of demineralized enamel more effectively than fluoride varnish .

Biomimetic remineralization of acid etched enamel using agarose hydrogel model.

Background: Minimally invasive dentistry aims to prevent progression of caries and treats non-cavitated lesions through non-invasive approaches to preserve the integrity of tooth structure. The aim of this research was to investigate the possible biomimetic effect of agarose hydrogel in remineralizing a human demineralized enamel model. Methods: Mandibular third molars were distributed into three groups (G1, G2 and G3) according to the follow up time (2, 4 and 6 days respectively). Caries like lesion was prepared by applying 37% phosphoric acid gel for 1 minute and then remineralization was performed through applying agarose hydrogel on the demineralized surfaces. The specimens were placed in phosphate solution at 37˚C for 2, 4 & 6 days. Scanning electron microscope (SEM), surface microhardness (SMH) and surface roughness analysis (SR) were performed to assess the regenerated tissue. Results: SEM revealed mineral depositions on the demineralized enamel surface that increased in density by time resulting in a relatively smooth surface in G3. SR and SMH analysis revealed significant differences between the remineralized enamel surfaces of different groups (p< 0.00001) with the highest SR in G1 and the highest SMH in G3. Conclusions: Agarose hydrogel application is a promising approach to treat early carious lesion. Further studies are needed to clarify the stability of agarose hydrogels in clinical application.

Effects of nano calcium carbonate and siwak toothpaste on demineralized enamel surface roughness

The aim of this study was to analyze the effect of nano calcium carbonate and Siwak toothpaste on demineralized enamel surface roughness. Human tooth specimens immersed in 0.3% citric acid at pH 3.25 were brushed with nano calcium carbonate and Siwak toothpaste for 2, 4, and 6 weeks. Enamel surface roughness was tested using a Surface Roughness Tester with supporting scanning electron microscopy and energy dispersive spectroscopy assessments. It was found the application of nano calcium carbonate and Siwak toothpaste for 2, 4, and 6 weeks decreased the surface roughness of the demineralized enamel (p < 0.05). Brushing teeth with nano calcium carbonate and Siwak toothpaste should decrease the surface roughness of demineralized enamel.

Effect of Siwak Extract on the Microhardness and Microscopic Feature of Initial Caries-Like Lesion of Permanent Teeth, Compared to Fluoridated Agents

Siwak is a chewing stick used to clean the teeth and message the gum. Theirroutine use was shown to be associated with the reduction in severity of dental caries.This study aimed to test the effect of water Siwak extract on the microhardness andmicroscopic features of artificially initiated carious lesion of the outer enamel surface,in comparison to stannous fluoride and sodium fluoride. Upper first premolars wereextracted and subjected to pH cycling procedure. Teeth immerged individually in 20ml of selected agents for four minutes then rinsed by de ionized water. Agentsinvolved were 5% and 10% water Siwak extract, 8% stannous fluoride and 0.05%sodium fluoride. Samples were subjected to Vickers microhardness test andmicroscopic examination before and after the pH cycling and following insertion inthe agents. Water Siwak extract, stannous fluoride and sodium fluoride were found toincrease the microhardness values of de mineralized enamel surfaces, this werestatistically highly significant for Siwak extract and stannous fluoride (P&lt; 0.01) andsignificant for sodium fluoride. However none of the mentioned agents was able toincrease the micro hardness to approximate the original values of the sound enamel.Under polarized light results revealed that water Siwak extracts and stannous fluorideproduce the best remineralization surface zone. Water Siwak extracts is very effectivein remineralization of initial carious lesion.

Microphotographic Assessment of Enamel Surface using Self-Etching Primer and Conventional Phosphoric Acid: An In vitro Study.

Introduction:Conventional acid-etching method irreversibly removes several microns of enamel surface and also involves many steps. Hence, a simplified technique that minimizes enamel loss, improves adhesion procedures, prevents saliva contamination, and saves chair time, thereby producing clinically useful bond strength, would be valuable.Aim:To assess and compare the bonding mechanism of a self-etching primer (SEP) to that of phosphoric acid on enamel of the human permanent teeth by a scanning electron microscope (SEM).Materials and Methods:Thirty freshly extracted premolars were randomly divided into two groups of fifteen teeth each – the control group I (phosphoric acid) and experimental group II (self-etching primer). Brackets were bonded using Transbond XT adhesive on the buccal surfaces of the teeth after etching and priming according to their respective protocols. The teeth were then sectioned and the samples were subjected to a protocol of demineralization cycles. After complete dissolution of dental tissues, the specimens were gold sputter coated and evaluated under SEM.Results:A characteristically uniform etch pattern was seen in the resin samples of the phosphoric acid/Transbond XT primer group, which revealed increased roughness and resin tags penetrating the demineralized enamel surface, whereas with Transbond Plus SEP, a regular resin tag distribution was observed which showed less magnitude when compared with the control group.Conclusion:From the study, it was concluded that Transbond Plus SEP produced an etch pattern which was more conservative than conventional phosphoric acid system.

Rapid biomimetic remineralization of the demineralized enamel surface using nano-particles of amorphous calcium phosphate guided by chimaeric peptides

ObjectiveThe objective of this study was to develop a rapid and effective method to remineralize human carious-like enamel using chimaeric peptide-mediated nanocomplexes of carboxymethyl chitosan/amorphous calcium phosphate (CMC/ACP), mimicking the mineralizing pattern of the oriented assembly of ACP guided by amelogenin in the biomineralization of enamel. MethodsCMC/ACP nanocomplex solution was first synthesized through the successive addition of carboxymethyl chitosan, calcium chloride, and dipotassium phosphate into distilled water. ACP nanoparticles were degraded by 1% NaClO from CMC/ACP nanocomplexes. The morphology of the particles at different periods was tested by transmission electron microscopy (TEM). The chimaeric peptides were added to guide the arrangement of ACP nanoparticles and to bind ACP nanoparticles to the demineralized enamel surface specifically. X-ray diffraction (XRD)/scanning electron microscope (SEM)/confocal laser scanning microscopy (CLSM)/nano-indentation tests were applied to check the remineralization effects. ResultsCMC/ACP nanocomplexes were obtained and could be kept without precipitation for a long time. After the degradation of NaClO and guidance of chimaeric peptides, ACP nanoparticles were arranged into oriented arrays before transforming into crystals, and the enamel-like crystals were tightly bound onto the demineralized surface. The newly formed enamel-like crystals were nearly well-organized and equipped with strong mechanical properties.

Remineralization of Natural Tooth Enamel in Artificial Saliva Environment

This paper investigates in situ remineralization of the acid-etched natural enamel surface, by incubation in a phosphate solution with neutral pH, at 37 �C for 4-10 days, without using any enamel matrix derivative (EMD). We investigated the morphology, crystallinity, chemical composition and structure of the newly grown layer onto the natural enamel surface stored in contact with artificial saliva (AS) having a composition similar to natural oral environment. The crystalline phases, crystallite size and orientation, as well as the chemical and phase composition of the remineralized dental enamel samples were studied by scanning electron microscopy coupled with energy dispersive X-ray spectrometry, Fourier transform infrared spectroscopy and X-ray diffraction. The experimental results showed that the enamel crystals grown on the demineralized enamel surface are mainly Ca-deficient apatite hexagonal structure. Fluoridated hydroxyapatite and sylvite-type KCl crystallites, which amount considerable increased in the case of sample stored in AS for 10 days, were also identified.

Comparison of enamel remineralization potential after application of titanium tetra fluoride and carbon dioxide laser.

The aim was comparison of enamel remineralization after application of APF, TiF4 and CO2 laser alone or in combination. Enamel blocks were prepared from human third molars. The initial surface hardness was determined by Vicker's hardness tester. The samples underwent a demineralization regimen for 7 days to produce artificial initial caries. The hardness of enamel blocks with white spot lesions was measured, and the samples which had the mean hardness change of 65-90%, were selected, and randomly divided into 5 groups (N=15): G1: control; G2: APF 1.23%; G3: TiF4 4%; G4: TiF4 4% followed by CO2 laser (10.6 µm wavelength, 1 W peak power, 10 ms pulse duration, 500 ms repeat time, 0.2 mm beam spot size, 2 cm distance); G5: CO2 laser (same parameters) followed by TiF4 4%. Surface hardness recovery was measured after the treatments. Three samples in each group were observed under scanning electron microscope at ×1,000 magnification. Data were analyzed by repeated measure ANOVA and Bonferrouni tests. Significance level was set at 0.05. G2, G3, G4 indicated significant differences with control and G5 (p<0.05). Surface hardness in G5 was not significantly different from control (p=0.7) in enamel hardness test. There was not a significant difference between G2 & G3, G2 & G4, and G3 & G4 (p=1). The SEM results indicated globules of calcium fluoride on the surface in G2, and a smooth glaze-like surface layer in G3 and G4. In G5, some micro-cracks without any glaze-like layer were observed. APF, TiF4 and TiF4 before CO2 laser irradiation significantly increased the micro-hardness of initially demineralized enamel surfaces. CO2 laser irradiation before TiF4 application could not remineralize the white-spot lesions.

Color Properties of Demineralized Enamel Surfaces Treated with a Resin Infiltration System

To assess color properties of white spot lesions (WSLs) following resin infiltration treatment in vitro. WSLs were artificially created on 30 extracted human teeth. Two groups were formed: (a) control, and (b) resin infiltrant group (n = 15, each). Instrumental color measurements were performed using a spectrophotometer and visual color evaluation was performed by three independent evaluators. Color assessment was determined at three time points: baseline (T0), after WSL formation (T1), and after resin infiltrant or control treatment (T2). CIELAB color coordinates were determined and the resultant color difference (ΔE*) was calculated between the time points. Two-way repeated measures analysis of variance (ANOVA) and One-way ANOVA analyses were used to evaluate the color changes. Pearson chi-square analysis was performed to evaluate the visual ratings between treatment and control groups. Level of significance was set p <0.05. After treatment of WSLs there was a significant color change (ΔE*) between treatment and control groups (p <0.05). Resin infiltration group showed a regression of all values toward the pretreatment levels. There was a significant difference in visual evaluation ratings between groups after treatment; treatment group had all surfaces receive a rating of being clinically acceptable, with 73% of these surfaces having no perceptible color difference to adjacent sound enamel. Meanwhile, control group received ratings of all surfaces having a visual color difference that was deemed as unacceptable (p < 0.05). In-vitro resin infiltration for the treatment of enamel WSLs produced a significant improvement in color, reverting L*, a*, and b* values back toward baseline values. Resin infiltration of enamel white spot lesions on teeth is capable of managing the esthetic problem by reverting the L*, a*, and b* color coordinates back to their baseline values. (J Esthet Restor Dent 28:339-346, 2016).

Remineralization Effects on the Demineralized Enamel of Primary Teeth by Fluoride Varnish

본 연구는 탈회 ìœ ì „ì¹˜ì— 3가지 불소바니쉬를 이용하여 인공우식의 재광화 효과를 비교 평가하였다. 인공우식용액에 40개의 ê±´ì „í•œ ìœ ì „ì¹˜ 시편을 ì¹¨ì ì‹œí‚¨ 후, 37℃ 항온기에 7일 동안 보관하여 ìœ ì „ì¹˜ì— 탈회를 형성하였다. Cavity shield™, V varnish™, MI varnish™를 1주일에 한 번씩 3주 동안 탈회된 ìœ ì „ì¹˜ì— 도포 후 불소바니쉬 ì¢ ë¥˜ì— 따른 미세경도 변화를 평가하였다.1주차에서는 MI varnish™군이 가장 높은 재광화 효과를 ë³´ì˜€ê³ ë‹¤ìŒìœ¼ë¡œ V varnish™군이 높았으며, Cavity shield™군이 낮은 재광화 효과를 보였으며, 세 êµ° 모두 ìœ ì˜í•œ 차이는 없었다(p > 0.05).2주차에서는 V varnish™군이 가장 높은 재광화 효과를 보였으며 ê·¸ 다음으로 MI varnish™군 높았지만 V varnish™군과 ìœ ì˜í•œ 차이는 없었다(p > 0.05). Cavity shield™군은 V varnish™군과 MI varnish™군에 비해 ìœ ì˜í•˜ê²Œ 낮은 재광화 효과를 보였다(p < 0.05). 3주차에서는 V varnish™군이 나머지 두 êµ°ê³¼ ìœ ì˜í•œ 차이를 보이며 가장 높은 재광화 효과를 ë³´ì˜€ê³ (p < 0.05), 다음으로 MI varnish™군이 높았으며 Cavity shield™군이 가장 낮은 재광화 효과를 보였지만, MI varnish™군과의 ìœ ì˜í•œ 차이는 없었다(p > 0.05). 총 미세경도 증가량은 Cavity shield™군에 비해 V varnish™군과 MI varnish™군이 높았으며(p < 0.05), V varnish™군과 MI varnish™군 사이 í†µê³„í•™ì  ìœ ì˜í•œ 차이는 없었다(p > 0.05).