|Year : 2017 | Volume
| Issue : 1 | Page : 30-39
In-vitro quantitative evaluation of the effectiveness of different techniques on the of incipient enamel demineralization
Sara A Gamea1, Wedad M Etman1, Ali I Abdalla1, Hussein I Saudi2
1 Department of Conservative Dentistry, Faculty of Dentistry, Tanta University, Tanta, Egypt
2 Department of Oral Medicine, Periodontology, Diagnosis, and Radiology, Faculty of Dentistry, Tanta University, Tanta, Egypt
|Date of Web Publication||14-Mar-2017|
Sara A Gamea
Saed Street, Nour Plaza Tower, Flat 4, 31111 Tanta
Source of Support: None, Conflict of Interest: None
Aim and objective: The aim of this study was to evaluate the effectiveness of three different techniques on treating induced incipient enamel demineralized lesions using digital subtraction radiography (DSR).
Materials and methods: Fifteen human sound premolars were used in this study. White spot lesions (WSLs) were established on the buccal, palatal, or lingual surfaces of the samples. Samples were then randomly divided into three equal groups (n = 10). Samples in group A were treated with ACT anticavity fluoride mouthrinse, those of group B were treated with MI paste Plus cream, while those of group C were treated with ICON resin infiltrant. All groups were exposed to a pH cycling, for 30 days excluding weekends where samples were stored in distilled water, during which the treatment regimen was applied. All groups were then exposed to a secondary demineralization attack. Standardized periapical radiographs were taken at four times interval; before any treatment which is considered as the baseline, after WSL creation, after material application, and lastly, after the second demineralization attack. DSR was used for the assessment of WSLs progression.
Results: Statistical analysis was conducted using one-way analysis of variance, Tukey's and paired t-tests (P < 0.05). Comparing the three methods of treatment; DSR evaluation showed that there was a statistically significant difference between the three groups, where group B had the best effect on decreasing the WSLs. Also, a significant difference was found among the three groups after the secondary demineralization attack, where group A was found to be the most resistant group.
Results: ACT mouthrinse, MI paste Plus, and ICON resin infiltrant are effective materials in treating the incipient lesions and in resisting caries recurrence.
Keywords: casein phosphopeptide amorphous calcium fluoride phosphate, fluoride, resin infiltration, white spot lesions
|How to cite this article:|
Gamea SA, Etman WM, Abdalla AI, Saudi HI. In-vitro quantitative evaluation of the effectiveness of different techniques on the of incipient enamel demineralization. Tanta Dent J 2017;14:30-9
|How to cite this URL:|
Gamea SA, Etman WM, Abdalla AI, Saudi HI. In-vitro quantitative evaluation of the effectiveness of different techniques on the of incipient enamel demineralization. Tanta Dent J [serial online] 2017 [cited 2021 Oct 19];14:30-9. Available from: http://www.tmj.eg.net/text.asp?2017/14/1/30/202061
| Introduction|| |
Dental caries is a highly prevalent disease, and although its prevalence has declined, the disease remains a major public health problem . Signs of the caries process cover a continuum from the first molecular changes in the apatite crystals of the tooth, to a visible white spot lesion (WSL), or even eventual cavitation. Progression through these stages requires a continual imbalance between pathological and protective factors leading to demineralization .
Demineralization is caused by acids of either intrinsic or extrinsic sources via bacterial metabolism of carbohydrates, or as a part of food and drinks . The demineralization can be reversed if the pH is neutralized and there are sufficient bioavailable calcium (Ca) and phosphate (PO4) ions in the immediate environment .
Approaches for the management of dental caries have changed dramatically in recent years, evolving from the traditional, or conservative restorative treatment approach to a preventive approach . A goal of modern dentistry, is to manage noncavitated caries lesions noninvasively through remineralization in an attempt to prevent disease progression and improve esthetics, strength, and function. The term 'remineralization' describes mineral gain, including precipitation of mineral onto enamel surfaces .
The incorporation of fluoride into dental materials has been highly recommended ,. Fluoride has been found to the keystone in protecting teeth against decay, strongly reducing enamel demineralization, and enhancing remineralization. Therefore, topically applied fluoridated products like toothpaste and mouthwash are widely used .
Remineralization of lesions has been successfully achieved by casein phosphopeptide (CPP) stabilized CaPO4 solutions , and an amorphous calcium phosphate (ACP) polymeric sealant which increased the concentrations of Ca, fluoride, and PO4 within the lesions exceeding those in oral fluids . It is proposed that this promotes remineralization of enamel WSLs .
A new approach in treating WSLs by an infiltration technique was introduced recently [13–15]. It is a microinvasive technology that fills, reinforces and stabilizes demineralized enamel, without drilling or sacrificing healthy tooth structure and preventing cavity formation . Hereby, diffusion pathways for cariogenic acids are blocked, and lesions are sealed .
| Materials and Methods|| |
Collection of teeth
Fifteen human sound premolars extracted from patients of an age range (15–25 years) for orthodontic purpose were selected. All patients are informed about the purpose of the study and using of their extracted teeth according to ethics committee of Faculty of Dentistry, Tanta University. The buccal and palatal or lingual surfaces with any visible signs of demineralization such as caries, white or brown spot lesion, cracks, erosion, abrasion, or any other developmental defects, were excluded from the study .
Samples cleaning and storage
The selected teeth were thoroughly cleaned under running tap water using soft toothbrush to remove plaque, blood, and remaining tissue tags. The teeth were then stored, refrigerated in normal saline solution which was changed daily and used within 1 month after extraction .
The crown of each tooth was longitudinally sectioned mesiodistally using a high speed diamond tipped disc to obtain buccal, palatal and lingual sections creating 30 samples. Each section was embedded in self-cure acrylic resin with the buccal and palatal or the lingual surface faced upward.
Two layers of acid-resistant nail varnish (Flormer, Milano, Italy) was applied on each sample, leaving a window of 3 × 3 mm of enamel exposed at the center of the sample. These established windows seen at the center of the tooth surface were then ready to be demineralized by immersing each sample in 40 ml of the first demineralizing solution for 72 h at 37°C in an incubator (Heraeus, Hanau, Germany) without stirring with a pH of 4, to create the artificial WSLs, the pH value was checked daily using a pH meter. After 72 h, all samples were taken out of the solution, and then rinsed with running tap water for 5 min, then rinsed again with distilled water for 30 s and dried with air spray free of oil to be visualized for their chalky white appearance .
After inducing the WSLs, samples were randomly divided into three equal groups (n = 10). Therapeutic agents were applied twice daily following the manufacturer's directions in a pH-cycling model over 30 days excluding weekends. The samples were immersed in a remineralizing solution to simulate the remineralizing oral fluid, then, they were exposed to the second demineralizing solution, which mimic the demineralizing oral fluid conditions.
Daily, samples were immersed in 20 ml of fresh remineralizing solution for 23 h, and 20 ml of fresh demineralizing solution for 1 h at 37°C in an incubator for a total of 30 days excluding weekends, where samples were stored in distilled water. On every solution exchange, samples were rinsed with distilled water for 10 s .
In group A, samples were immersed in 10 ml of ACT anticavity mouthrinse according to manufacturer's instructions for 1 min twice daily during the cycling then rinsed with distilled water and dried with an oil free air spray for 10 s after each application.
In group B, MI Paste Plus was applied to the enamel windows by an applicator brush and left undisturbed for 3 min according to manufacturer's instructions twice daily during the cycling. The paste was rinsed with distilled water and dried with an oil free air spray for 10 s after each application.
While in group C, samples were infiltrated with ICON resin infiltrant before the cycling. Each sample required ~10 min to complete etching and treatment according to the manufacturer's instructions.
All groups were then exposed to a secondary demineralization attack. A standardized custom-made square adhesive sticker with a diameter of 3 × 3 mm were reapplied on each treated area, and a second layer of acid-resistant nail varnish were then applied to all samples and allowed to dry. Once the varnish was dry, the stickers were peeled off using a tweezer. All samples were immersed in 40 ml of the same demineralizing solution, used for initial demineralization, for 72 h at 37°C in the incubator without stirring. After 72 h, all samples were taken out of the solution, and the samples were then rinsed with water.
For each sample standardized periapical radiographic films were taken at four different intervals; at the baseline, after WSL creation, after material application, and lastly, after the second demineralization cycle. The radiographs were shot using size 0 speed D periapical films (Carestream Kodak Co., Rochester, New York, USA). A custom-made device was used to standardize the projection geometry at subsequent radiographic shots. An X-ray machine operating (Xgenus De Gotzen S.r.l, Rome, Italy) at 70 kV, 10 mA and 0.5 s was used to take the radiographic films. All the radiographic films were processed at the same time by using a fresh solution in an automatic processing operator (Dürr Dental AG, Bietigheim-Bissingen, Germany) according to the manufacturer's specification under standardized conditions. The radiographs were digitized with the same principle and equipment using HP Scanjet G3110 flatbed scanner (Hp Invent Comp., USA), All images were scanned at 600 dot per inch (dpi) resolution and 255 gray levels, and saved in JPEG format. The collected images were analyzed using Visual Basic Program (Microsoft Comp., USA) based on the subtraction concept .
The collected data were tabulated and statistically analyzed using one-way analysis of variance (ANOVA), Tukey's and t-tests at P value less than or equal to 0.05 significance level using statistical package for social sciences, version 20 (SPSS Inc., Chicago, Illinois, USA).
| Results|| |
Digital subtraction radiography revealed data of the different steps for each of the three groups: A, B and C.
Step 1: subtraction of the image pixels after WSL creation from those of the baseline ([Table 1] and [Figure 1]).
|Table 1: Statistical analysis of the values of radiographic pixels subtraction after white spot lesion creation from those at the baseline among all groups (mean±SD)|
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|Figure 1: (a) Representative X-ray images of a sample showing the subtraction of image pixels after WSL creation from those of baseline in group A; Left image : After WSL creation. Middle image :Subtracted image. Right image: At baseline. (b) The Green colour represents the subtracted spots.|
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Step 2: subtraction of the image pixels after treatment material application from those after WSL creation ([Table 2] and [Figure 2]).
|Table 2: Statistical analysis of the values of radiographic pixel subtraction after applying treatment materials from those after white spot lesion creation among all groups (mean±SD)|
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|Figure 2: (a) Representative X-ray images of a sample showing the subtraction of image pixels after ACT® application from those after WSL creation; Left image: After ACT® application. Middle image: Subtracted image. Right image: After WSL creation. (b) The Green colour represents the subtracted spots.|
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Step 3: subtraction of the image pixels after second demineralization attack from those after material application ([Table 3] and [Figure 3]).
|Table 3: Statistical analysis of the values of radiographic pixel subtraction after second demineralization attack from those after applying treatment materials among all groups (mean±SD)|
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|Figure 3: (a) Representative X-ray images of a sample showing the subtraction of image pixels after 2nd demineralization attack from those after ACT®application; Left image: After 2nd demineralization attack. Middle image: Subtracted image. Right image: After ACT® application. (b) The Green colour represents the subtracted spots.|
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Regarding group A: ANOVA test revealed no statistical significant difference between the mean pixel values of the samples after WSL creation, and those after applying ACT ([Table 1]). On the contrary, a significant difference was found in the same group between the mean pixel values of the samples after WSL creation versus those after second demineralization attack, and between the mean pixel values of the samples after treatment with ACT versus those after second demineralization attack where the amount of demineralization after WSL creation and the amount of remineralization after treatment with ACT was greater than the amount of demineralization after second demineralization attack ([Table 4]).
|Table 4: Statistical analysis of the pixel values of each group between the different steps (mean±SD)|
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Similar findings were found group C where no statistical significant difference between the mean pixel values of the samples after WSL creation, and those after applying ICON. While, a significant difference was found in the same group between the mean pixel values of the samples after WSL creation versus those after second demineralization attack, and between the mean pixel values of the samples after treatment with ICON versus those after second demineralization attack ([Table 4]).
While in group B; ANOVA test revealed a statistical significant difference between the mean pixel values of the samples after WSL creation, and those after applying MI paste Plus which reveals a greater amount of remineralization after MI paste Plus application than the amount of demineralization after lesion creation. Also, a significant difference was found in the same group between the mean pixel values of the samples after WSL creation versus those after second demineralization attack, and between the mean pixel values of the samples after treatment with MI paste Plus versus those after second demineralization attack ([Table 4]).
Comparing the effect of the three treatment materials in improving the WSLs, F-test revealed a statistical significant difference between the mean values of pixel subtraction recorded after applying treatment materials versus those after WSL creation among all groups. A pair-wise Tukey's test was then performed; and revealed that group B has the greatest pixel values compared with groups A and C. While comparing group A versus group C, no significant difference was found ([Table 2]).
While comparing the effect of the three treatment materials in resisting further acid attack, F-test revealed a statistical significant difference between the mean values of pixel subtraction recorded after second demineralization attack versus those after applying treatment materials among all groups. Tukey's test was then performed; and revealed that group A has the least pixel values followed by group B then group C ([Table 3]).
| Discussion|| |
In modern dentistry, it has been widely accepted that no cavity design or restorative material is required to cure a carious lesion. The original anatomy, strength, and esthetics of the tooth might be lost forever in case of restoration. The continuum of replacement dentistry, with repeatedly enlarged restorations and increased damage of hard tissues, has led to the development of multiple prevention strategies that center on the prompt treatment for the disease at an early stage and include measures which, remineralize, arrest, and/or reverse the caries process after initiation of clinical signs . So, our current study was performed to compare different techniques for the treatment and prevention of WSLs.
A fluoride mouthrinse, dental cream containing CPP-amorphous calcium phosphate fluoride (ACPF) and caries resin infiltrate, were evaluated to find their effect on treating induced incipient enamel demineralized lesions and the resistance of these treated lesions to further acid attack.
Digital subtraction radiography analysis has been used to measure the mineral changes of human enamel since it provides a relatively simple, sensitive, nondestructive and rapid quantitative method in demineralization and remineralization studies .
The aggressive demineralization attack which was done in the present study, was used to achieve the cumulative effect of years in a more realistic time frame .
A pH cycling was performed in this study to simulate the remineralizing and demineralizing oral fluid conditions. The 1 h duration in the demineralization solution approximates the accumulated acid challenge times in a 24 h period that occurs in the oral cavity . It should be noted that individuals may have more or fewer acid challenges than those recorded in the 1 h total time, depending on dietary habits and biofilm compositions , however this was to standardize the conditions in the study.
Noninvasive treatment of WSLs by remineralization, represent a major advance in clinical management of the disease. Fluoride is considered from the best established remineralization strategy so it was chosen according to the finding which indicates that it is an efficient agent to aid remineralization and prevent demineralization of teeth, making it the reference agent against which new remineralizing agents are compared .
In the present study, the effect of ACT mouthrinse has been evaluated where the mean values of pixel values after WSL creation versus those after applying ACT showed no significant difference, which means that the degree of demineralization after WSL creation was equal to the degree of remineralization after applying ACT. This may be explained by the fact that, in the presence of the Ca and PO4 ions, which are produced during demineralization of the tooth enamel by acids, fluoride ions immediately promote the formation of FA or CaF2 , and was able to close the opened pores by its remineralization effect.
In accordance with our study, studies by Zero et al.  showed that a 0.05% NaF mouthrinse (225 ppm fluoride) used for 1 min gave elevated fluoride levels in saliva for 2–4 h and in plaque for much longer times. Similar results were found by the studies of Meyerowitz et al. , and Geiger et al. . Also, Songsiripradubboon et al.  reported the high efficiency of 0.05% NaF mouthrinse in remineralization and recommended its use in high–caries-risk patients.
After the material application all groups were exposed to a secondary demineralization cycle, which corresponds to what happens in the follow-up periods in vivo, to evaluate the possible protection effect that has been afforded by the treatment agents and the resistance of the treated lesions to further demineralization.
Also according to our results, the current statistical analysis of the mean of pixel values after WSL creation versus those after second demineralization attack or pixel values after applying ACT versus those after second demineralization attack revealed a statistical significant difference finding out that the amount of demineralization after second demineralization attack was lesser than the amount of demineralization after lesion creation and lesser than the degree of remineralization after treatment with ACT. So according to the previous results, ACT mouthrinse was found to be an effective method in resisting secondary demineralization. Thus it can be concluded that ACT mouthrinse is an effective type of treatment for WSLs and resisting any further demineralization.
Several studies reported that the efficacy of fluoride in resisting caries is due to its lower solubility . In all studies, FA was found to dissolve appreciably more slowly than hydroxyapatite. Our results was congruent with, Chow et al. , and Crommelin et al.  who suggested that fluoride rich mineral is considerably more resistant to demineralization than fluoride poor mineral and all of them assured that that significant protection against demineralization could be obtained when the hydroxyapatite crystals along the acid ions diffusion pathway are coated with FA.
When the treatment by MI paste Plus was currently evaluated, the statistical analysis revealed that comparing the mean pixel values after WSL creation versus those after applying MI paste Plus there was a statistically significant difference between the two steps, where the amount of remineralization after applying MI paste Plus was greater than the amount of demineralization after WSL creation, revealing that MI paste plus is an effective method in treating the WSLs.
Again, in the MI paste Plus group, statistical analysis of the mean of pixel values after WSL creation versus those after second demineralization attack and the pixel values after applying MI paste Plus versus those after second demineralization attack were compared with test the ability of the MI paste Plus treated teeth to resist further demineralization revealing that there was a statistically significant difference. It was concluded that the amount of demineralization after second demineralization cycle was lesser than the demineralization after first demineralization cycle and lesser than the amount of remineralization after application of MI pate Plus.
Accordingly, MI paste Plus was found to be an effective method in resisting secondary demineralization. This can be explained by the low solubility of Ca and PO4 in the presence of fluoride, 20 so when CPP stabilize ACPF and form the CPP-ACPF phase, the ACP binds the free fluoride ion and localizes it (in the form of FA crystals), with the Ca and PO4 ions, on the enamel surface, which was able to resist secondary demineralization .
These results come in agreement with a study made by Uysal et al. , who reported that CPP-ACPF (MI paste Plus) was an effective treatment for remineralizing enamel lesions. Similarly, the studies of Srinivasan et al. , Wu et al. , Robertson et al. , Hamba et al.  and Jayarajan et al.  proved the efficiency of CPP-ACPF in WSLs remineralization.
Again, in agreement with our study results, Shetty et al.  did an in-vitro study of 50 enamel samples, the results showed that there was an improved enamel remineralization in the group, remineralized using CPP-ACPF in comparison with the other groups.
However, in contrast with our results, a study made by Huang et al.  found that MI paste Plus did not appear to be an effective treatment for WSLs over an 8-week period. The authors claimed these results to the biased assessments due to lack of blinding to the evaluators as photographic assessment was used for WSLs clinical assessment.
The porosities of enamel caries act as diffusion pathways for acids and dissolved minerals. So, infiltration of these lesions with resin might occlude the pathways, thereby preventing cavitation or breakdown of the enamel surface and aid in the arrest of WSLs progression ,. ICON is an innovative product for the microinvasive treatment of early cariogenic lesions in the proximal and vestibular regions. It involves the use of low-viscosity light curing resins composed of TEGDMA which completely fills the pores within the tooth, replacing lost tooth structure and stopping caries progression ,.
It penetrates into the lesion by capillary forces and creates a diffusion barrier inside the lesion and not only on the lesion surface . The use of 15% HCl for etching the surface layer is effective and postulated to be beneficial for deeper infiltration of the resin into the body of the lesion . Also, the use of solvents such as ethanol, acetone and water in resin infiltrates show lower surface tension and viscosities compared with materials without solvents. This material shows higher PC and penetrates up to the depth of the WSL and not just mask it. So, we chose to study the effect of ICON treatment on WSLs.
According to our results, ICON resin infiltrate was found to be an effective method in treating the WSLs since there was no statistically significant difference between the amount of remineralization after ICON application cycling and the amount of opened pores after first demineralization cycle. This could be due to its' ability to penetrate the WSLs by its capillary forces facilitating the ingress of fluoride, Ca and PO4.
Moreover, ICON resin infiltrate was found to be an effective method in resisting secondary demineralization since the statistical analysis of the mean pixel values after WSL creation versus those after second demineralization attack and the mean pixel values after applying effect of ICON versus those after second demineralization attack, revealed that there was a statistically significant difference observing that the amount of demineralization after second demineralization cycle was lesser than the amount of demineralization after WSL creation and lesser than the amount of remineralization after application of ICON. This could be attributed to its' ability to create a barrier against further diffusion of organic acids, which stabilize and effectively blocks the caries pathway ,.
In accordance with our results, the studies of Paris et al. , Paris et al. , Senestraro et al. , Subramaniam et al. , and de Oliveira et al.  demonstrated the increased demineralization resistance of ICON infiltrated lesions.
Also, in agreement with our study results, a radiographic study done by Paris et al. , evaluated the progression of lesion after infiltration. The study was a randomized split-mouth placebo-controlled trial. Twenty-nine pairs of proximal caries lesions from 22 young adults were included in the study, with lesions having to be in the inner half of the enamel and outer third of the dentin. Radiographs were taken at baseline for evaluation. ICON infiltration was performed on the test group and placebo was used for the control group. Manufacturer's instructions were followed for the treatment with ICON and water was used as treatment in the control group (placebo). The results showed that in the ICON treated lesions, 7% of the lesions showed progression, while in the placebo 37% lesions showed progression.
Martignon et al.  completed the previous study by reporting the 3-year efficacy of ICON to arrest progression of proximal noncavitated caries lesions as compared with placebo treatment. No unwanted effects were observed. Radiographically 1/26 (4%) test lesions and 11/26 (42%) control lesions had progressed. So they concluded that ICON was effective in inhibiting further demineralization.
Moreover, a systematic review by Doméjean et al. , aimed to evaluate the in-vivo scientific evidence of the ability of resin infiltration to arrest noncavitated caries lesions. The PubMed database was searched for randomized controlled trials that evaluated the in-vivo effect of resin infiltration versus placebo or other preventive treatment on the progression of caries lesions. Four articles reported on proximal caries lesions. One study had been conducted on 48 high-caries-risk children while the other three (n = 22, 22 and 39, respectively) concerned moderate-caries-risk and low-caries-risk adolescents and adults. The quality of the studies was assessed to be high with respect to randomization, split-mouth design and blinding. All the included studies showed significant differences in caries progression between test and control/placebo groups, indicating that resin infiltration may inhibit the carious process. This systematic review revealed that resin infiltration appeared to be an effective method to arrest the progression of noncavitated caries lesions which is the same what our study demonstrated.
According to the current study results, MI paste Plus showed a superior effect compared with both the ACT and ICON groups, regarding its' effect to remineralize initially demineralized enamel surfaces.
However, statistical analysis revealed that ACT was superior to MI paste Plus and ICON in resisting secondary demineralization, which may be due to the fact that FA crystals or CaF2 ions which were formed after ACT mouthrinse treatment was more stable on the enamel surface against the acid attack.
Our results come in agreement with a study by Reynolds et al.  proved that a dentifrice containing CPP-ACPF was superior to a dentifrice containing fluoride in remineralization of enamel lesions in situ. Similarly, Shen et al.  reported a synergy between CPP-ACP and fluoride with a 3.7-fold increase in remineralization level following the use of Tooth Mousse Plus, as compared with a fluoride toothpaste. Also, our results come in agreement with the studies of Badr et al. , Krithikadatta et al.  and Juárez-López et al.  who found that CPP-ACPF was better than NaF in WSLs treatment.
However, in contrast with our results, a study done by Rehder Neto et al.  compared the effect of different oral pastes on bovine dental surfaces with induced caries-like lesions (pH-cycling protocol). Remineralization of the tooth surfaces was seen with the different remineralizing agents tested (toothpaste with fluoride, MI paste, MI paste with fluoride and Tooth Revitalizing Paste containing Novamin). Higher amounts of mineral changes on the enamel surfaces were obtained with the fluoride toothpaste and Tooth Revitalizing Paste, while MI paste and MI paste Plus gave lower changes in mineral levels. The pastes containing the CPP-ACP were effective in increasing remineralization. Nevertheless, higher remineralization was achieved with fluoride and Novamin pastes. This contradiction with our results may be due to the different application protocol, since in the previous study treatments were applied five times, after the deremineralization period in the cariogenic challenges.
An in-vitro study was conducted by Lata et al.  on enamel blocks of human premolars with the aim of evaluating the remineralization potential of fluoride and CPP-ACP and the combination of CPP-ACP and fluoride on early enamel lesions. They concluded that; CPP-ACP cream is effective, but to a lesser extent than fluoride in remineralizing early enamel caries at surface level. Combination of fluoride and ACP-CPP does not provide any additive remineralization potential compared with fluoride alone. These results were contradictory to our results which reported the reverse of the previous results.
In relation to the effect of NaF and CPP-ACPF in resisting demineralization, Wegehaupt et al.  showed that tooth wear after erosive attacks could be reduced significantly by daily application of NaF in comparison with CPP-ACPF, which was the same found in our study. It has been hypothesized that there is poor affinity of CPP-ACP to enamel in an erosive challenge. Under acidic condition, casein carries a positive charge, and consequently its affinity to enamel may be reduced. Also, a study made by Moezizadeh et al. , found that 0.05% NaF mouthwash is more effective than CPP-ACPF in prevention of dentin erosion.
Also, in accordance with our results, Nasab et al. made a study to compare the effects of 0.05% NaF mouthrinse, GC Tooth Mousse and GC MI paste Plus on WSL formation inhibition. Thirty pairs of extracted human premolars were cut in half mesiodistally with a disc. They concluded that, although 0.05% NaF mouthrinse, GC Tooth Mousse and GC MI paste Plus are effective preparations to inhibit WSL formation, NaF mouthrinse has better efficacy than CPP-ACP products. Another randomized in-situ trial comparing the protective effect of NaF and CPP-ACPF by Wiegand et al.  reported that the use of a NaF mouthrinse was highly effective in resisting enamel and dentine demineralization than CPP-ACPF, which did not show any protective effect.
Confliction between researches' findings was apparent in the comparison between the effect of fluoride and ICON on WSL treatment. Our results were contradictory to a study done by Lu et al.  who compared the efficiency of resin infiltration and fluoride varnish for treatment of WSLs and they found that resin infiltration treatment was better than fluoride. Also, Gelani et al.  assessed the ability of ICON to prevent artificial lesion progression in vitro when used to impregnate WSLs in relation to other treatment regimens including fluoride. They concluded that the use of ICON alone or in conjunction with fluoride inhibited further demineralization of early enamel lesions in vitro more efficiently than fluoride alone. However, a study by Torres et al.  concluded that the effect of ICON was similar to the effect of 0.05% NaF mouthrinse. This confliction may be related to differences in the experimental protocols or to the method of assessment of WSLs.
| Conclusion|| |
ACT mouthrinse, MI paste Plus, and ICON resin infiltrant are effective materials in treating the incipient lesions and in resisting caries recurrence.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Selwitz RH, Ismail AI, Pitts NB. Dental caries. Lancet 2007; 369:51–59.
Cochrane NJ, Cai F, Huq NL, Burrow MF, Reynolds EC. New approaches to enhanced remineralization of tooth enamel. J Dent Res 2010; 89:1187–1197.
Hamba H, Nikaido T, Inoue G, Sadr A, Tagami J. Effects of CPP-ACP with sodium fluorides on inhibition of bovine enamel demineralization: a quantitative assessment using micro-computed tomography. J Dent 2011; 39:405–413.
Barbour ME, Parker DM, Allen GC, Jandt KD. Enamel dissolution in citric acid as a function of calcium and phosphate concentrations and degree of saturation with respect to hydroxyapatite. Eur J Oral Sci 2003; 111:428–433.
Tung MS, Eichmiller FC. Amorphous calcium phosphates for tooth mineralization. Compend Contin Educ Dent 2004; 25:S9–S13.
Cury JA, Tenuta LM. Enamel remineralization: controlling the caries disease or treating early caries lesions? Braz Oral Res 2009; 23:23–30.
Ten Cate JM. Current concepts on the theories of the mechanism of action of fluoride. Acta Odontol Scand 1999; 57:325–329.
Sano H, Nakashima S, Songpaisan Y, Phantumvanit P. Effect of xylitol and fluoride containing toothpaste on the remineralization of human enamel in vitro
. J Oral Sci 2007; 49:67–73.
Reynolds EC, Cai F, Shen P, Walker GD. Retention in plaque and remineralization of enamel lesions by various forms of calcium in a mouthrinse or sugar-free chewing gum. J Dent Res 2003; 82:206–211.
Reynolds EC, Cai F, Cochrane NJ, Shen P, Walker GD, Morgan MV, et al.
Fluoride and casein phosphopeptide-amorphous calcium phosphate. J Dent Res 2008; 87:344–348.
Skrtic D, Hailer AW, Takagi S, Antonucci JM, Eanes ED. Quantitative assessment of the efficacy of amorphous calcium phosphate/methacrylate composites in remineralizing caries-like lesions artificially produced in bovine enamel. J Dent Res 1996; 75:1679–1686.
Bailey DL, Adams GG, Tsao A, Hyslop CE, Escobar K, Manton DJ, et al.
Regression of post-orthodontic lesions by a remineralizing cream. J Dent Res 2009; 88:1148–1153.
Meyer-Lueckel H, Paris S. Improved resin infiltration of natural caries lesions. J Dent Res 2008; 87:1112–1116.
Paris S, Meyer-Lueckel H, Colfen H, Kielbassa AM. Resin infiltration of artificial enamel caries lesions with experimental light curing resins. Dent Mater J 2007; 26:582–588.
Paris S, Meyer-Lueckel H, Kielbassa AM. Resin infiltration of natural caries lesions. J Dent Res 2007; 86:662–666.
Kielbassa AM, Muller J, Gernhardt CR. Closing the gap between oral hygiene and minimally invasive dentistry: a review on the resin infiltration technique of incipient (proximal) enamel lesions. Quintessence Int 2009; 40:663–681.
Paris S, Hopfenmuller W, Meyer-Lueckel H. Resin Infiltration of caries lesions: an efficacy randomized trial. J Dent Res 2010; 89:823–826.
Namrata P, Shantanu CH, Sadanand K, Saurabh RJ. Comparative evaluation of remineralization potential of three agents on artificially demineralized human enamel: an in vitro
study. J Conserv Dent 2013; 16:116–120.
Langhorst SE, O'Donnell JN, Skrtic D. In vitro
remineralization of enamel by polymeric amorphous calcium phosphate composite: quantitative microradiographic study. Dent Mater 2009; 25:884–891.
El-Kalla IH, Saudi HI, El-Agamy RA. Effect of adhesive resin application on the progression of cavitated and non-cavitated incipient carious lesions. J dent 2012; 25:176–180.
Longbottom C, Ekstrand K, Zero D, Kambara M. Novel preventive treatment options. Monogr Oral Sci 2009; 21:156–163.
Ricketts J, Ekstrand K, Martignon S, Ellwood R, Alatsaris M, Nugent Z. Accuracy and reproducibility of conventional radiographic assessment and subtraction radiography in detecting demineralization in occlusal surfaces. Caries Res 2007; 41:121–128.
Weir MD, Chow LC, Xu HH. Remineralization of demineralized enamel via calcium phosphate nanocomposite. J Dent Res 2012; 91:979–984.
Rolla G. On the role of calcium fluoride in the cariostatic mechanism of fluoride. Acta Odontol Scand 1988; 46:341–345.
Ogard B, Seppa L, Rolla G. Professional topical fluoride applications-clinical efficacy and mechanism of action. Adv Dent Res 1994; 8:190–201.
Zero DT, Raubertas RF, Pedersen AM, Fu J, Hayes AL, Featherstone JDB. Fluoride concentrations in plaque, whole saliva and ductal saliva after applications of home-use fluoride agents. J Dent Res 1992; 71:1768–1775.
Meyerowitz C, Featherstone JDB, Billings RJ, Eisenberg AD, Fu J, Shariati M, et al.
Use of an intra-oral model to evaluate 0.05% sodium fluoride mouth rinse in radiation induced hyposalivation. J Dent Res 1991; 70:894–898.
Geiger AM, Gorelick L, Gwinnett AJ, Benson BJ. Reducing white spot lesions in orthodontic populations with fluoride rinsing. Am J Orthod Dentofacial Orthop 1992; 101:403–407.
Songsiripradubboon S, Hamba H, Trairatvorakul C, Tagami J. Sodium fluoride mouthrinse used twice daily increased incipient caries lesion remineralization in an in situ
model. J Dent 2014; 3:271–278.
Rosin-Grget, LI. Current concept on the anticaries fluoride mechanism of the action K. Coll Antropol 2001; 25:703–712.
Chow LC. Tooth bound fluoride and dental caries. J Dent Res 1990; 69:595–600.
Crommelin DJ, Hieguchi WI, Fox IL, Spooner PJ, Katdare AV. Dissolution rate behaviour of hydroxyapatite-fluorapatite mixtures. Caries Res 1983; 17:289–296.
Cross KJ, Huq NL, Reynolds EC. Casein phosphopeptides in oral health – chemistry and clinical applications. Curr Pharm Des 2007; 13:793–800.
Uysal T, Amasyali M, Koyuturk AE, Ozcan S. Effects of different topical agents on enamel demineralization around orthodontic brackets: an in vivo
and in vitro
study. Aust Dent J 2010; 55:268–274.
Srinivasan N, Kavitha M, Loganathan SC. Comparison of the remineralization potential of CPP-ACP and CPP-ACP with 900 ppm fluoride on eroded human enamel: an in situ
study. Arch Oral Biol 2010; 55:541–544.
Wu G, Liu X, Hou Y. Analysis of the effect of CPP-ACP tooth mousse on enamel remineralization by circular polarized images. Angle Orthod 2010; 80:933–938.
Robertson MA, Kau CH, English JD, Lee RP, Powers J, Nguyen JT. MI Paste Plus to prevent demineralization in orthodontic patients: a prospective randomised controlled trial. Am J Orthod 2011; 140:660–668.
Jayarajan J, Janardhanam P, Jayakumar P, Deepika P. Efficacy of CPP-ACP and CPP-ACPF on enamel remineralization: an in vitro
study using scanning electron microscope and DIAGNOdent. Indian J Dent Res 2011; 22:77–82.
] [Full text]
Shetty S, Hegde MN, Bopanna TP. Enamel remineralization assessment after treatment with three different remineralizing agents using surface microhardness: an in vitro
study. J Conserv Dent 2014; 17:49–52.
Huang GJ, Roloff-Chiang B, Mills BE, Shalchi S, Spiekerman C, Korpak AM, et al.
Effectiveness of MI Paste Plus and PreviDent fluoride varnish for treatment of white spot lesions: a randomized controlled trial. Am J Orthod Dentofacial Orthop 2013; 143:31–41.
Meyer-Lueckel H, Paris S, Mueller J, Colfen H, Kielbassa AM. Influence of the application time on the penetration of different dental adhesives and a fissure sealant into artificial subsurface lesions in bovine enamel. Dent Mater 2006; 22:22–28.
Meyer-Lueckel H, Paris S, Kielbassa AM. Surface layer erosion of natural caries lesions with phosphoric and hydrochloric acid gels in preparation for resin infiltration. Caries Res 2007; 41:223–230.
Paris S, Meyer-Lueckel H. Inhibition of caries progression by resin infiltration in situ
. Caries Res 2010; 44:47–54.
Paris S, Dörfer CE, Meyer-Lueckel H. Surface conditioning of natural enamel caries lesions in deciduous teeth in preparation for resin infiltration. J Dent 2010; 38:65–71.
Paris S, Schwendicke F, Seddig S, Müller WD, Dörfer C, Meyer-Lueckel H. Micro-hardness and mineral loss of enamel lesions after infiltration with various resins: Influence of infiltrant composition and application frequency in vitro
. J dent 2013; 41:543–548.
Senestraro SV, Crowe JJ, Wang M, Vo A, Huang G, Ferracane J, Covell DAJr. Minimally invasive resin infiltration of arrested white-spot lesions: a randomized clinical trial. J Am Dent Assoc 2013; 144:997–1005.
Subramaniam P, Girish KL, Lakhotia D. Evaluation of penetration depth of a commercially available resin infiltrate into artificially created enamel lesions: an in vitro
study. J Conserv Dent 2014; 17:146–149.
] [Full text]
De Oliveira G, Boteon A, Ionta F, Moretto M, Honório H, Wang L, et al
. In vitro
effects of resin infiltration on enamel erosion inhibition. Oper Dent 2015; 40:492–502.
Paris S, Meyer-Lueckel H. Infiltrants inhibit progression of natural caries lesions in vitro
. J Dent Res 2010; 89, 1276–1280.
Martignon S, Ekstrand, KR, Gomez J, Lara JS, Cortes A. Infiltrating/sealing proximal caries lesions: a 3-year randomized clinical trial. J Dent Res 2012; 91:288–292.
Doméjean S, Ducamp R, Léger S, Holmgren C. Resin infiltration of non-cavitated caries lesions: a systematic review. Med Princ Pract 2015; 24:216–221.
Shen P, Manton DJ, Cochrane NJ, Walker GD, Yuan Y, Reynolds C, et al
. Effect of added calcium phosphate on enamel remineralization by fluoride in a randomized controlled in situ
trial. J Dent 2011; 39:518–525.
Badr SB, Ibrahim MA. Protective effect of three different fluoride pretreatments on artificially induced dental erosion in primary and permanent teeth. J Am Sci 2010; 6:442–451.
Krithikadatta J, Fredrick C, Abarajithan M, Kandaswamy D. Remineralisation of occlusal white spot lesion with a combination of 10% CPP-ACP and 0.2% sodium fluoride evaluated using Diagnodent: a pilot study. Oral Health Prev Dent 2013; 11:191–196.
Juárez-López ML, Hernández-Palacios RD, Hernández-Guerrero JC, Jiménez-Farfán D, Molina-Frechero N. Preventive and remineralization effect over incipient lesions of caries decay by phosphopeptide-amorphous calcium phosphate. Rev Invest Clin 2014; 66:144–151.
Rehder Neto FC, Maeda FA, Turssi CP, Serra MC. Potential agents to control enamel caries- like lesions. J Dent 2009; 37:786–790.
Lata S, Varghese NO, Varughese JM. Remineralization potential of fluoride and amorphous calcium phosphate-casein phospho peptide on enamel lesions: an in vitro
comparative evaluation. J Conserv Dent 2010; 13:42–46.
Wegehaupt FJ, Attin T. The role of fluoride and casein phosphopeptide/amorphous calcium phosphate in the prevention of erosive/abrasive wear in an in vitro
model using hydrochloric acid. Caries Res 2010; 44:358–363.
Moezizadeh M, Alimi A. The effect of casein phosphopeptide-amorphous calcium phosphate paste and sodium fluoride mouthwash on the prevention of dentine erosion: an in vitro
study. J Conserv Dent 2014; 17:244–249.
] [Full text]
Nasab NK, Davalloo R, Alavi FN. The effect of NaF mouthrinse, GC Tooth Mousse and GC MI Paste Plus on white spot inhibition: an invitro study. J Dentomaxillofac Radiol Pathol Surg 2012; 1:20–25.
Wiegand A, Attin T. Randomised in situ
trial on the effect of milk and CPP-ACP on dental erosion. J Dent 2014; 42:1210–1215.
Lu W, Jie J, Hui-fang L. Efficiency of resin infiltration versus fluride varnish for treatment of post-orthodontic white spot lesions. Efficiency of resin infiltration versus fluride varnish for treatment of post-orthodontic white spot lesions. Chinese J Tissue Eng Res 2013; 29.
Gelani R, Zandona AF, Lippert F, Kamocka MM, Eckert G. In vitro
progression of artificial white spot lesions sealed with an infiltrant resin. Oper Dent 2014; 39:481–488.
Torres CR, Rosa PC, Ferreira NS, Borges AB. Effect of caries infiltration technique and fluoride therapy on microhardness of enamel carious lesions. Oper Dent 2012; 37:363–369.
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4]