Protective effect on enamel demineralization of a CPP-ACP paste: an AFM in vitro study

The effect of combined use of resin infiltration with different bioactive calcium phosphate-based approaches on enamel white spot lesions: An in vitro study

OBJECTIVES

This in vitro study aimed to evaluate the effect of resin infiltration combined with casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) or bioactive glass (BAG) on the stability of enamel white spot lesions (WSLs) treatment.

MATERIALS AND METHODS

Eighty-four enamel blocks were prepared from the buccal surfaces of sound human premolars. All enamel blocks were placed in a demineralisation solution for 3 days to establish the artificial enamel WSLs. Enamel blocks with WSLs were randomly divided into three groups (n = 28 each group): RI/B: one-off resin infiltration followed by twice daily BAG treatment; RI/C: one-off resin infiltration followed by twice daily CPP-ACPF treatment; RI: one-off resin infiltration treatment only (as control) and subjected to pH cycling for 7 days. Surface morphology, elemental analysis, crystal characteristics, surface roughness and microhardness of enamel surfaces were investigated by scanning electron microscopy and energy-dispersive spectrometry observation, X-ray diffraction (XRD), atomic force microscope and Vickers' hardness testing, respectively.

RESULTS

Mean values of the surface roughness (mean±standard deviation (nm)) were 24.52±5.07, 27.39±5.87 and 34.36±4.55 for groups RI/B, RI/C and RI respectively (p = 0.003). The calcium to phosphate ratios were 1.32±0.16, 1.22±0.26 and 0.69±0.24 for groups RI/B, RI/C and RI respectively (p < 0.001). XRD revealed apatite formation in all three groups. The mean enamel surface microhardness (kg/mm2) of the groups were 353.93±28.49, 339.00±27.32 and 330.38±22.55 for groups RI/B, RI/C and RI respectively (p = 0.216).

CONCLUSIONS

Resin infiltration combined with CPP-ACPF or BAG remineralisation appears to improve the surface properties of WSLs.

CLINICAL SIGNIFICANCE

The combination of resin infiltration and CPP-ACPF/BAG remineralisation may be a potential treatment for the management of the WSLs.

Efficiency of Various Tubular Occlusion Agents in Human Dentin after In-Office Tooth Bleaching

The aim of this laboratory study was to investigate and compare the impact of five desensitizing techniques as a treatment fortooth sensitivity on the exposed dentin after an in-office tooth bleaching procedure. Thirty intact human molars were collected for this investigation. The specimens were obtained by transversely cutting 2.5 mm of the crowns, leading to exposure of the dentin. The specimens were cleaned in an ultrasonic bath and treated initially with EDTA gel 15% for 4 min and then with Opalescence Boost bleaching gel (40% H2O2) for two sets of 20 min. Then, the samples were randomly divided into six groups (n = 5) and received one of the following treatments: Group 1 (no treatment-control group), Group 2 (Emofluor gel-0.4% SnF2), Group 3 (MI Paste-CPP-ACPF), Group 4 (BioMinF paste-calcium phospho-fluoro-silicate), Group 5 (air-abrasion with ProSylc-Bioglass 45S5), and Group 6 (Er,Cr:YSGG laser). Subsequently, each sample was observed utilizing scanning electron microscopy (SEM) in order to detect the rate of occlusion of dentin tubules. SEM-EDS analysis revealed no occlusion of the dentin tubules in the control group, while Groups 2, 4, and 5 presented high effectiveness (>95% percentage of occluded tubules), and Groups 3 and 6 presented lower values (21.6 and 26.8%, respectively). It was concluded that althoughall the tested groups presented higher percentages of occlusion of the dentinal tubules compared to the control group, there were differences in effectiveness among them. The most effective treatments were the daily use of BioMinF paste and SnF2-containing gel, as well as air-abrasion with ProSylc powder.

Remineralization effect of three different agents on initial caries and erosive lesions: a micro-computed tomography and scanning electron microscopy analysis

BACKGROUND

This study aimed to investigate the remineralization efficiency of Sensodyne Promine containing Sodium flouride (NaF), GC Tooth Mousse containing CPP-ACP, and Agarta herbal toothpaste on initial caries and erosion using micro-computed tomography (CT) and scanning electron microscopy (SEM).

METHODS

Forty-five third-molar teeth for micro-CT were divided into three main groups after initial scans (T₁) were completed. Artificial caries lesions were created with the demineralization cycle (group 1, n = 15) and artificial erosion lesions were created with orange juice (group 2, n = 15) and Cola (group 3, n = 15), and second scans (T₂) were performed. The groups were divided into three subgroups within themselves. Sensodyne Promine toothpaste (subgroup 1a, 2a, 3a), GC Tooth Mousse topical cream (subgroup 1b, 2b, 3b), and Agarta herbal toothpaste (subgroup 1c, 2c, 3c) were applied using soft-tipped brushes for 2 min, twice per day for 15 days, and then a third scan (T₃) was performed. Mineral density, surface area, and lesion volume and depth were calculated using micro-CT. Changes in the surface morphology of the teeth were examined using SEM in 13 samples representing each group, subgroup, and healthy enamel. In the analysis of the data obtained from the scans performed at three different times (T₁, T₂, T₃), one-way analysis of variance (ANOVA) with the post-hoc Tukey test, repeated measures ANOVA with the post-hoc Bonferroni test, and paired sample t-test analyses were used.

RESULTS

All three agents caused a statistically significant increase in mineral density, and a decrease in surface area and lesion volume and depth (p < 0.05). There was no statistically significant difference between the groups in remineralization efficiency (p > 0.05). A statistically significant difference was found between the groups regarding the mineral density of the tissue that increased after remineralization (NaF > CPP-ACP > He; p < 0.05).

CONCLUSION

The remineralization efficacy of herbal toothpaste as an alternative to NaF and CPP-ACP was found to be successful.

Effect of three different remineralizing agents on artificial erosive lesions of primary teeth

BACKGROUND

This study aimed to investigate the efficacy of three remineralizing agents on dental erosion in primary teeth.

METHODS

Forty primary molars were randomly divided into four groups (n = 10 each): self-assembling peptide (P_11-4 ), casein phosphopeptide-amorphous calcium fluoride phosphate (CPP-ACFP), sodium fluoride (NaF) and artificial saliva (AS; control). The erosion-like formation was created by immersing the samples in citric acid (4 × 2 min, pH 2.3) and AS (4 × 2 h, pH 7). The eroded samples were then treated with remineralizing agents and subjected to further erosion consisting of 15 cycles (3x/8-h interval) of immersion in citric acid and AS for 6 s each. Alterations in the mineral content and morphology of the samples were quantified using a microhardness tester and atomic force microscope.

RESULTS

All agents had a significant remineralization effect on eroded primary tooth enamel. After further erosive challenge, enamel loss in the CPP-ACFP group was found to be significantly lower than in all other groups, and no significant difference was found between the P_11-4 and NaF groups.

CONCLUSIONS

This study showed that all tested materials had remineralization ability, and CPP-ACFP had a superior effect in inhibiting enamel loss due to dental erosion in primary teeth. © 2022 Australian Dental Association.

Casein phosphopeptide amorphous calcium phosphate and universal adhesive resin as a complementary approach for management of white spot lesions: an in-vitro study

Background

White spot lesion (WSL) is the most common consequence during and after orthodontic treatment. This study was conducted to investigate the ability of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) coupled with universal adhesive resin to treat white spot lesions.

Material and methods

Forty-five extracted premolars were sectioned to create 90 specimens. Seventy-five specimens were demineralized to generate artificially created WSLs. Different strategies have been applied for the management of the artificially created WSLs. Six experimental groups were employed: Group I: sound enamel (control), Group II: demineralized enamel (artificially-created WSLs), Group III: ICON resin-treated WSLs, Group IV: CPP-ACP-treated WSLs, Group V: universal adhesive resin-treated WSLs, and Group VI: CPP-ACP followed by universal adhesive resin-treated WSLs. Assessment of color stability using a spectrophotometer, surface microhardness using a Vickers tester, and surface roughness using a profilometer was done. The surface topography of representative specimens from each experimental group was inspected using a scanning electron microscope. Collected data were analyzed using one-way ANOVA followed by Tukey’s post hoc test at p ≤ 0.05.

Results

White spot lesions treated with CPP-ACP and subsequently coated with universal adhesive resin (Group VI) exhibited a significantly lower ΔE than both CPP-ACP (Group IV) and universal adhesive resin-treated (Group V) groups (p ≤ 0.05), but it was not significantly different from the ICON resin-treated group (Group III). For surface microhardness, WSLs treated with CPP-ACP and consequently coated with universal adhesive resin (Group VI) recorded the highest mean that was significantly different from both ICON resin (Group III) and universal adhesive resin-treated (Group V) groups (p ≤ 0.05). All the tested strategies (ICON resin, CPP-ACP, universal adhesive resin, and CPP-ACP followed by universal adhesive resin) significantly lowered the surface roughness of the WSLs (p ≤ 0.05), while no significant difference was detected among them.

Conclusions

Combining a considerable caries remineralizing program using CPP-ACP with subsequent universal adhesive resin infiltration could be a promising approach to manage WSLs efficiently through increasing surface microhardness and restoring esthetic while developing a smoother surface.

Sub-micro scale cell segmentation using deep learning

Automated cell segmentation is key for rapid and accurate investigation of cell responses. As instrumentation resolving power increases, clear delineation of newly revealed cellular features at the sub-micron through nanoscale becomes important. Reliance on manual investigation of myriad small features retards investigation; however, use of deep learning methods has great potential to reveal cell features both at high accuracy and high speed, which may lead to new discoveries in the near term. In this study, semantic cell segmentation systems were investigated by implementing fully convolutional neural networks called U-nets for segmentation of astrocytes cultured on Poly-L-lysine-functionalized planar glass. The network hyperparameters were determined by changing the number of network layers, loss functions, and input image modalities. Atomic force microscopy (AFM) images were selected for investigation as these are inherently nanoscale and are also dimensional. AFM height, deflection, and friction images were used as inputs separately and together, and the segmentation performances were investigated on five-fold cross-validation data. Transfer learning methods, including VGG16, VGG19, and Xception, were used to improve cell segmentation performance. We find that AFM height images inherit more discriminative features than AFM deflection and AFM friction images for cell segmentation. When transfer learning methods are applied, statistically significant segmentation performance improvements are observed. Segmentation performance was compared to classical image processing algorithms and other algorithms in use by considering both AFM and electron microscopy segmentation. An accuracy of 0.9849, Matthews correlation coefficient of 0.9218, and Dice's similarity coefficient of 0.9306 were obtained on the AFM test images. Performance evaluations show that the proposed system can be successfully used for AFM cell segmentation with high precision. This article is protected by copyright. All rights reserved.

Comparative Evaluation of the Effect of Different Beverages on the Surface Roughness and Microhardness of Human Enamel Surface: An In Vitro Study

Milk-derived beverages are considered to be beneficial to not only health but also to dental tissue. However, the exact nature of the effect of these beverages should be studied to formulate an exact diet plan for a child so that only good effects can be obtained from a dietary derivative.

Rehardening and the Protective Effect of Gamma-Polyglutamic Acid/Nano-Hydroxyapatite Paste on Surface-Etched Enamel

Many revolutionary approaches are on the way pertaining to the high occurrence of tooth decay, which is an enduring challenge in the field of preventive dentistry. However, an ideal dental care material has yet to be fully developed. With this aim, this research reports a dramatic enhancement in the rehardening potential of surface-etched enamels through a plausible synergistic effect of the novel combination of γ-polyglutamic acid (γ-PGA) and nano-hydroxyapatite (nano-HAp) paste, within the limitations of the study. The percentage of recovery of the surface microhardness (SMHR%) and the surface parameters for 9 wt% γ-PGA/nano-HAp paste on acid-etched enamel were investigated with a Vickers microhardness tester and an atomic force microscope, respectively. This in vitro study demonstrates that γ-PGA/nano-HAp treatment could increase the SMHR% of etched enamel to 39.59 ± 6.69% in 30 min. To test the hypothesis of the rehardening mechanism and the preventive effect of the γ-PGA/nano-HAp paste, the surface parameters of mean peak spacing (Rsm) and mean arithmetic surface roughness (Ra) were both measured and compared to the specimens subjected to demineralization and/or remineralization. After the treatment of γ-PGA/nano-HAp on the etched surface, the reduction in Rsm from 999 ± 120 nm to 700 ± 80 nm suggests the possible mechanism of void-filling within a short treatment time of 10 min. Furthermore, ΔRa-I, the roughness change due to etching before remineralization, was 23.15 ± 3.23 nm, while ΔRa-II, the roughness change after remineralization, was 11.99 ± 3.90 nm. This statistically significant reduction in roughness change (p < 0.05) implies a protective effect against the demineralization process. The as-developed novel γ-PGA/nano-HAp paste possesses a high efficacy towards tooth microhardness rehardening, and a protective effect against acid etching.

Evaluation of the protective effect on enamel demineralization of CPP-ACP paste and ROCS by vibrational spectroscopy and SAXS: An in vitro study

The aim of this study was to investigate human dental enamel surfaces using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, and small angle X-ray scattering (SAXS) techniques concerning differences between the demineralized enamel surface and remineralized enamel surface by casein phosphopeptide amorphous calcium phosphate, Tooth mousse® (CPP-ACP) and remineralizing oral care systems (ROCS®) agents within the same tooth. For this purpose, 20 freshly extracted human maxillary central incisors without caries and defects were used. Labial surfaces of each of the teeth were divided into four sections, which were marked as follows: Group 1, normal enamel; Group 2, demineralized enamel with demineralization solution; Group 3, demineralized enamel + remineralization agent (ROCS for 10 teeth, CPP-ACP for 10 teeth); and Group 4, remineralization agent (ROCS for 10 teeth, CPP-ACP for 10 teeth). To describe the changes in tooth enamel, the phosphate group concentration within enamel was used as an indicator of the degree of mineralization. The phosphate and carbonate bands in the FTIR and Raman spectra were used to investigate the structural changes in the demineralized and remineralized enamel. Spectroscopic data were statistically analyzed in terms of CPP-ACP and ROCS using one-way analysis of variance. The carbonate content of demineralized enamel was higher than the carbonate content in the other groups (p < .03). The apatite carbonate-phosphate balance in the samples with only remineralizing agent-especially ROCS applied-changed significantly (p < .05) compared to the normal group. The average FTIR spectra of the groups were subjected to multivariate hierarchical cluster analysis (HCA) conducted with the use of the OPUS 5.5 software. Nanosized surface morphologies of the samples were compared using pair distance distributions obtained through SAXS analyses. According to the SAXS analyses, applications of CCP + ACP and ROCS agents were effective on nanostructures for all groups.

Enamel Erosion: A Possible Preventive Approach by Casein Phosphopeptide Amorphous Calcium Phosphate-An In Vitro Study

Context

Several efforts were made in order to alter the compositions of acidic food items concerning their properties to be able to reduce their erosivity potential. The addition of combinations of calcium and phosphate salts to these food products has grabbed great interest.

Aim

In vitro evaluation of the effect of the addition of 0.2% w/v casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) to four commonly available beverages (of which two were carbonated) on enamel erosion.

Materials and methods

Sound-extracted human third molar teeth were taken, and enamel sections (n = 270) were made and polished. Acid-resistant nail varnish was painted to create an exposed enamel window of 1 mm², followed by testing of the four soft drinks and distilled deionized water (DDW). Every drink was evaluated with and without the addition of 0.2% w/v CPP–ACP. The enamel specimens were kept in 50 mL solution at 37°C for 30 minutes, rinsed, and then varnish was removed. All samples were then profiled using white-light profilometer, and erosive depths were recorded.

Statistical analysis

One-way analysis of variance test and post hoc Tukey test.

Results

Enamel erosion was created by all the soft drinks tested, but the addition of 0.2% w/v CPP–ACP has remarkably reduced (p value < 0.05) erosive depths in all test solutions compared to solutions without CPP–ACP. The erosive depths for solutions with DDW did not vary much from those with 0.2% CPP–ACP.

Conclusion

Addition of 0.2% w/v CPP–ACP to the soft drinks has remarkably reduced their erosivity potential.

How to cite this article

Velagala D, Reddy VN, Achanta A, et al. Enamel Erosion: A Possible Preventive Approach by Casein Phosphopeptide Amorphous Calcium Phosphate—An In Vitro Study. Int J Clin Pediatr Dent 2020;13(5):486–492.

Evaluation of the efficacy of casein phosphopeptide-amorphous calcium phosphate on remineralization of white spot lesions in vitro and clinical research: a systematic review and meta-analysis

BACKGROUND

This systematic review with meta-analyses sought to answer whether casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) provided a remineralizing benefit superior to that of nonintervention or placebo.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, Cochrane databases, PubMed, EmBase, and Ovid up to May 20th, 2019, were scanned, only published in English. Study information extraction and methodological quality assessments were accomplished independently by two reviewers. The "Criteria for judging risk of bias in the 'Risk of bias' assessment tool" was used for methodological quality assessment. The continuous data was analyzed by mean difference (MD) or standardized mean difference (SMD) with a 95% confidence interval (CI). Review Manager 5.3 was used for statistical analysis. Outcome variables include quantitative light-induced fluorescence in clinical research, average surface roughness and surface microhardness in vitro.

RESULTS

There were significant differences in the quantitative light-induced fluorescence (SMD = - 0.43, 95% CI: [- 0.79, - 0.07], P = 0.02), average surface roughness (SMD = - 8.21, 95% CI: [- 10.37, - 6.04], P < 0.01), Vickers microhardness (SMD = 1.19, 95% CI: [0.72, 1.66], P < 0.01), and Knoop microhardness (SMD = 3.52, 95% CI: [2.68, 4.36], P < 0.01) between the CPP-ACP and control groups or baseline.

CONCLUSION

Within the limitations of this meta-analysis, CPP-ACP exhibited excellent remineralization effects evaluated in clinical research and in vitro, indicating outstanding restoration of form, aesthetics, and function in treating white spot lesions.

Effect of air-abrasion pre-treatment with bioactive glass 45S5 on enamel surface loss after erosion/abrasion challenge

OBJECTIVES

The aim of this in vitro study was to evaluate the effect of air-abrasion surface pre-treatment with bioactive glass (BAG) 45S5 on enamel surface loss after erosion/abrasion challenge.

METHODS

Twenty-four sound bovine incisors were used for this study. Four experimental groups (n=12) were assigned as follows: Group 1 was the negative control group, Group 2 specimens were treated with a SnF₂ gel (positive control group), Group 3 specimens were air-abraded with BAG 45S5 (ProSylc) and Group 4 received both treatments. The specimens were submitted to erosion/abrasion challenge using a common soft drink. Enamel surface loss was evaluated using an optical profilometer. Additionally, surface roughness (VSI method) and surface microhardness (Vickers method) changes were evaluated, as well as SEM and EDS analyses were performed on enamel surface. The data were statistically analyzed using one-way ANOVA and Tukey's post-hoc test at a level of significance a=0.05.

RESULTS

Surface pre-treatment with BAG 45S5 reduced surface loss in comparison with negative control group (p<0.001), which exhibited the highest surface loss of the experimental groups (p<0.05). The positive control group (SnF₂ treatment) and Group 4 specimens, which received both air-abrasion pre-treatment and SnF₂ treatment, presented the lowest surface loss (p<0.05), but did not show significant differences to each other (p=0.65).

SIGNIFICANCE

Air-abrasion pre-treatment with BAG 45S5 may be beneficial as an in-office preventive method for the limitation of enamel erosive wear induced by excessive consumption of soft drinks. The clinical significance of the results regarding this preventive method should be confirmed by clinical studies.

The longevity of casein phosphopeptide-amorphous calcium phosphate fluoride varnish's preventative effects: Assessment of white spot lesion formation

OBJECTIVES

To test how long casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) fluoride varnish prevents enamel demineralization in vitro.

MATERIALS AND METHODS

Human molars and premolars were sectioned buccolingually and randomly assigned to two groups. Standardized pretreatment images of enamel surfaces were obtained using FluoreCam. The control group received no treatment, and the experimental group received an application of CPP-ACP fluoride varnish. Over simulated periods of 2, 4, 8, and 12 weeks, specimens were placed in a toothbrushing simulator, thermocycled, subjected to 9 days of pH cycling, and imaged with FluoreCam. Samples were sectioned and polished for polarized light microscope (PLM) evaluation.

RESULTS

There were statistically significant time ( P < .001) and varnish ( P < .001) effects on area, intensity, and impact of enamel demineralization. The control group showed significant and progressive demineralization over the 12 weeks ( P < .001). The experimental group revealed no significant demineralization during the first 4 weeks ( P > .05) and significant ( P < .001) increases thereafter. Experimental demineralization after 12 weeks was comparable to 2-week demineralization in the controls, with significant between-group differences ( P < .001) in enamel demineralization at all time points. PLM of the control and experimental groups revealed lesion depths of 90 ± 34 μm and 37 ± 9 μm, respectively.

CONCLUSIONS

Within the limitations of this in vitro study, CPP-ACP fluoride varnish prevents enamel demineralization for at least 4 weeks and limits demineralization up to 12 weeks.

Coupling xylitol with remineralizing agents improves tooth protection against demineralization but reduces antibiofilm effect

To explore the efficiency of xylitol chewing gum enriched or not with remineralizing agents to protect tooth against cariogenic biofilm formation and demineralization. Six groups of chewing gums were prepared; Group 1: isomalt (1.8%), Group 2: casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) (3%) + isomalt (1.8%), Group 3: hydroxyapatite (HAP) (2.5%) + isomalt (1.8%), Group 4: xylitol (1.8%), Group 5: CPP-ACP (3%) + xylitol (1.8%) and Group 6: HAP (2.5%) + xylitol (1.8%). The antibiofilm properties of different chewing gum extracts using seven oral bacterial species including Streptococcus mutans, Streptococcus constellatus, Streptococcus Salivarius and Streptococcus oralis were explored via the crystal violet staining assay. The remineralizing effects of those products were assessed on thirty human permanent teeth, half-protected with varnish before chemical erosion and thermocycling process with chewing gum. Remineralization was evaluated using scanning electron microscopy and microscopic measurements on polarized light microscopy. The ratio R comparing the thickness between unvarnished and varnished sides was evaluated. While the minimum biofilm inhibitory concentration (MBIC₅₀) was low for xylitol alone compared to isomalt, it was inconsistent when enriched with remineralizing agents. The minimum biofilm eradication concentration (MBEC₅₀) was low for xylitol groups compared to isomalt, for all the studied strains. R was significantly lower in Group 1 and Group 2, while Group 6 showed the highest ratio. Xylitol chewing gums confirmed good antibiofilm properties and showed remineralized potential on eroded teeth. When xylitol is associated to CPP-ACP or HAP, antibiofilm activity decreased while remineralization of eroded teeth increased.

Comparative evaluation of grape seed and cranberry extracts in preventing enamel erosion: An optical emission spectrometric analysis

Introduction:

Dental erosion is defined as the loss of tooth structure due to chemical process that does not involve bacteria. The management of such a condition calls for a comprehensive approach to identifying the cause and treating it.

Aim:

The aim of this study is to comparatively evaluate the role of grape seed extract (GSE) and cranberry extract (CE) in preventing dental erosion using optical emission spectrometry.

Materials and Methods:

Prepared enamel specimens were subjected to the erosive challenge using HCl for 10 s, followed by immersion in experimental natural groups and control fluoride group for 30 s and artificial saliva for 60 min. This cycle was repeated three times. The amounts of calcium and phosphorous present in the acid solution after 1^st, 2^nd, and 3^rd erosive challenges were determined for each group using induced coupled plasma-optical emission spectrometry.

Results:

The cumulative calcium and phosphorous release after the 1^st, 2^nd, and 3^rd erosive challenges were found to be the least in SnF2 group, followed by GSE group and then in CE group.

Conclusion:

The protective of GSE and CE was inferior to the gold standard control group of stannous fluoride role, against enamel erosion. GSE showed better remineralizing effect; however, there was no statistically significant difference between the two groups.

Fluoride Varnishes against Dental Erosion Caused by Soft Drink Combined with Pediatric Liquid Medicine

Abstract The present study evaluated the effect of NaF and CPP-ACP/NaF varnishes to reduce erosion produced by soft drink (SD) combined or not with pediatric liquid medicine. Enamel specimens were pre-treated with fluoride varnish, according to the following groups: NaF varnish (Duraphat®) or CPP-ACP/NaF varnish (MI varnishTM). Two types of erosive cycles were made: by soft drink erosion (SDE) or by pediatric liquid medicine plus soft drink erosion (PLM/SDE). Bovine enamel specimens were randomly assigned in six groups (n=10): G1=NaF + SDE; G2=CPP-ACP/NaF + SDE; G3=Distilled and deionized (DD) water + SDE; G4=NaF + PLM/SDE; G5=CPP-ACP/NaF + PLM/SDE and G6=DD water + PLM/SDE. Before treatments, the sample surface was divided in two areas (unexposed area-UA and exposed area-EA). The specimens were evaluated by 3D non-contact profilometry technique to determinate tooth structure loss (TSL) and surface roughness (Sa). Scanning electron microscopy (SEM) analysis was also performed. After SDE, G2 presented the lowest TSL values compared to G3 (p=0.008). G1 and G2 did not differ between them (p=0.203) and no groups differed among them despite Sa. Regarding TSL and Sa, G4 and G5 differed from G6 (p=0.0001), but not between them (p=1.00). Examining 3D and SEM images, the greatest differences between UA and EA were observed for G3 and G6. CPP-ACP/NaF varnish seems to be a promising treatment to reduce enamel loss from the erosion produced by a soft drink. Both varnishes also showed capacity to reduce TSL and Sa after erosion by soft drink combined to pediatric liquid medicine.

Micro-CT and FE-SEM enamel analyses of calcium-based agent application after bleaching

OBJECTIVES

The objective of the present study is to evaluate the effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on bleached enamel.

MATERIALS AND METHODS

A bleaching agent (35% hydrogen peroxide) was applied, 4 × 8 min on premolar teeth (n = 8). A CPP-ACP paste was applied for 7 days. Prior and post-treatment, microtomography images were obtained and 3D regions of interest (ROIs) were selected, from outer enamel, extending to 110.2-μm depth. CT parameters of structure: thickness (St.Th), separation (St.Sp), and fragmentation index (Fr.I.) were calculated for each (ROI). Data was submitted to paired t tests at a 95% confidence level. The samples were evaluated at 3000 to 100,000 magnification. Quantitative analysis of enamel mineral content was also determined by SEM EDX.

RESULTS

There was a significant increase in structure thickness and calcium content. The phosphorus content increased after bleaching. There was also a decreased separation and fragmentation index on the outer enamel to a depth of 56.2 μm (p < 0.05). There were no changes at 110.2-μm depth for the bleaching CPP-ACP association. A covering layer and decreased spaces between the hydroxyapatite crystals appeared around the enamel prisms, 7 days after the CPP-ACP application.

CONCLUSIONS

The application of a CPP-ACP provides a compact structure on the enamel's outer surface, for 7 days, due to calcium deposition. CT parameters seem to be a useful tool for mineralizing and remineralizing future studies.

CLINICAL RELEVANCE

CPP-ACP neutralizes any adverse effects on enamel surface when applied during a week after bleaching and minimizes any side effects of the bleaching treatment due to a more compact structure.

Is It Necessary to Prepare the Enamel before Dental Bleaching?

The aim of this in vitro study was to assess the influence of distinct surface treatments on the microhardness and color of enamel that will be bleached. Surface treatments are tested, accordingly: G1, no treatment; G2, 2% sodium fluoride; G3, casein phosphopeptide paste; G4, 2% fluoride+Nd:YAG laser. Forty blocks from bovine teeth composed the sample that were tested in Knoop microhardness (n = 10) and in color change (n = 10). After 24 h, bleaching with 35% hydrogen peroxide was performed for 45 min. Microhardness and color changes (using parameters ΔE, ΔL, Δa, and Δb) were assessed before and after bleaching. The data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). Despite all surface treatments, a reduction of enamel microhardness occurred immediately after bleaching in all groups, being greater in G1. Enamel color changed in all groups. Immediately after bleaching, there was a decrease on enamel microhardness. However, after 7 days, some of those specimens previously treated before bleaching significantly recovered their initial microhardness without influencing the esthetic results of bleaching.

Resin infiltrant for non-cavitated caries lesions: evaluation of color stability

BACKGROUND

The objective of this in vitro study was to evaluate the over time color stability of one resin infiltrant (Icon) upon exposure to staining solutions (coffee and wine) compared with one nano-hybrid sealant (Grandio Seal), one transparent fissure sealant with fluoride (Control Seal) and one nanofilled composite (Filtek Supreme XTE).

MATERIAL AND METHODS

All materials were polymerized according to manufacturers' instructions into silicon rings (height 1 mm; internal diameter 6 mm; external diameter 8 mm) to obtain specimens identical in size. The specimens were immersed in staining solutions at room temperature over a 28-day test period. The control samples have not been subjected to the staining process. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. Shapiro Wilk test and Kruskal Wallis ANOVA were applied to assess significant differences among different materials. Means were compared with Scheffe's multiple-comparison test at the 0.05 level of significance.

RESULTS

In the case of all materials, immersion in solutions resulted in clinically perceivable color changes after 1 week (∆E < 3.3). Lowest CIE L* variation was registered for Control Seal and Grandio Seal both after 1 week and after 1 month, while Icon showed significantly higher variation (P < 0.05). Color coordinate CIE a* varied significantly more for Icon samples (P > 0.05). Color coordinate CIE b* varied similarly for all materials tested (P > 0.05).

CONCLUSIONS

Immersion in coffee or red wine resulted in clinically perceivable color changes for all materials tested. Icon showed the highest color variations both after 1 week and 1 month. Icon can fix the initial esthetic problem associated with white spot lesions, but the resin may become more discolored than other materials over time. Key words:CIE Lab, color stability, resin infiltrant.

Effect of Fluoride Varnish Containing CPP-ACP on Preventing Enamel Erosion

This study aimed to investigate the effect of a fluoride varnish with added casein phosphopeptide-amorphous calcium phosphate treatment on the prevention of enamel erosion, and it compared the results with those of other fluoride varnishes. Fifty enamel specimens obtained from bovine incisors were randomly divided into five groups (n = 10) based on the type of surface pretreatment used: intact enamel (Group 1); intact enamel+erosive cycles (Group 2); intact enamel+MI varnish+erosive cycles (Group 3); intact enamel+Clinpro White varnish+erosive cycles (Group 4); and intact enamel+Duraphat varnish+erosive cycles (Group 5). The specimens were subjected to erosive cycles for five days. The surface roughness was evaluated using atomic force microscopy. The results were statistically analyzed using one-way ANOVA and Tukey's tests. Group 1 had the smoothest surfaces. After the erosive cycles, the greatest surface roughness values were observed in Group 2, followed by Groups 5, 4, and 3, respectively. Statistically significant differences were observed among all groups (p < 0.05). The application of fluoride varnishes had some positive effects on preventing enamel erosion; however, the most effective agent was fluoride varnish with added casein phosphopeptide-amorphous calcium phosphate.

Effect of fluoride varnish with added casein phosphopeptide-amorphous calcium phosphate on the acid resistance of the primary enamel

Background

This study aimed to investigate the effects of a fluoride varnish with added Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) treatments on acid resistance of primary teeth enamel.

Methods

Enamel specimens obtained from 40 primary incisors (for surface microhardness testing) and 40 primary molars (for demineralization depth measurement) were randomly divided into four groups (n = 10 incisors and 10 molars) each according to surface treatment: no treatment (control), MI varnish (1–8 % sodium fluoride and 1–5 % CPP-ACP), Clinpro White (1–5 % sodium fluoride and <5 % modified tricalcium phosphate), Duraphat (<5 % sodium fluoride). Specimens were stored for 24 h in a moist environment. After varnish residues were removed, specimens were subjected to pH cycling. The effects of fluoride varnishes were evaluated according to surface microhardness, lesion depth and structural changes. Results were analyzed by ANOVA and Tukey’s tests.

Results

The lowest changes in surface microhardness and lesion depth occurred in MI varnish group, followed by the Clinpro White, Duraphat and no treatment (control) group (for percentage of loss surface microhardness −20.80, −34.60, −57.80 and −73.40; for lesion depth values 23.60 μm ± 3.36, 29.85 μm ± 3.27, 40.37 μm ± 3.41 and 54.56 μm ± 4.16, respectively). Statistically significant differences in both surface microhardness and lesion depth were observed among all groups (P < 0.05).

Conclusions

Within the limitations of this in vitro study, fluoride varnish containing CPP-ACP was more effective in increasing the acid resistance of primary enamel than other fluoride varnishes. However, further clinical research is needed to confirm these in vitro results.

Enamel lesions: Meta-analysis on effect of prophylactic/therapeutic agents in erosive tissue loss

This study aims to perform a meta-analysis on the effect of prophylactic/therapeutic agents in enamel tissue loss due to erosion. A paper search was done on Medline, PubMed, Embase, and Cochrane Library, and 732 papers were identified. The inclusion criteria were very restrictive in order to be able to compare different protocols and methodologies used on those studies. Sixteen papers were eligible, grouped according to the measurement method of enamel tissue loss, and a meta-analysis was done for each type of fluoride- and casein-based agent applied. Standardized mean differences were pooled across studies. There was a significant difference between all the treatment groups and their respective control groups. The highest standardized mean difference on enamel tissue loss (mean; 95% confidence interval) was obtained by stannous fluoride (4.789 μm; 1.968-7.610; P < 0.001), followed by amine fluoride (2.485 μm; 0.746-4.225; P < 0.010), and titanium tetrafluoride (1.787 μm; 1.106-2.469; P < 0.001); the lowest difference was obtained by casein phosphopeptide-amorphous calcium phosphate (0.869 μm; 0.007-1.731; P < 0.050) and sodium fluoride (0.820 μm; 0.417-1.223; P < 0.001). Stannous fluoride as a fluoride-based prophylactic/therapeutic agent allowed the lowest enamel tissue loss in erosive conditions. Standardization among future study protocols will allow better comparison regarding the prophylactic/therapeutic agent with the best clinical efficacy.

Nano-hydroxyapatite could Compensate the Adverse Effect of soft carbonated Drinks on Enamel

INTRODUCTION

Since one of the most important disadvantages of soft drinks includes their adverse effect on mineral content of enamel because of their low pH, this study examined the microhardness of enamel before and after exposure to a soft drink containing different concentrations of nano-hydroxyapatite (nano-HA) as an additive.

MATERIALS AND METHODS

Sixty caries free human premolars were mounted in epoxy resin. After polishing, the baseline micro-hardness was recorded three times for each specimen using a Vickers indenter at 50 gm load. Subsequently, the samples were divided into six groups, which were treated for 5 minutes at 9°C by a cola-based drink contacting 0, 0.5, 1, 5, and 10 wt.% of nano-HA while the control group was immersed in artificial saliva. Ultimately, the final microhardness was assessed three times again for each specimen.

RESULTS

Paired t-test showed that in groups containing 0 and 0.5 wt.% of nano-HA, the microhardness was significantly reduced after treatment protocol (p = 0.00 and 0.01 respectively). Whereas in the other groups the microhardness was not significantly changed after treatment (p > 0.05).

CONCLUSION

Pure cola-based drink has a pronounced adverse effect on enamel microhardness, while admixing it with nano-HA could act as a protective factor.

CLINICAL SIGNIFICANCE

Although soft beverages are hazardous to tooth structure, some additives could compensate their adverse effect.

In situ Effect of Chewing Gum with and without CPP-ACP on Enamel Surface Hardness Subsequent to ex vivo Acid Challenge

The erosion-protective effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is controversial. This study aimed to investigate the ability of CPP-ACP chewing gum to prevent a single event of erosive demineralization in situ. Bovine enamel blocks (n = 120) were randomly assigned to 3 phases according to the baseline surface hardness: phase I (PI) - chewing gum with CPP-ACP, phase II (PII) - chewing gum without CPP-ACP, and control phase (PIII) - salivary effect without stimulation (no gum). Nineteen volunteers participated in this study during 3 crossover phases of 2 h. In PI and PII, the volunteers wore intraoral palatal appliances for 120 min and chewed a unit of the corresponding chewing gum for the final 30 min. In the control phase the volunteers wore the appliance for 2 h, without chewing gum. Immediately after intraoral use, the appliances were extraorally immersed in a cola drink for 5 min to promote erosive demineralization. The percentage of surface hardness loss was calculated. The data were analyzed by ANOVA models and Tukey's test. Lower enamel hardness loss was found after the use of chewing gum with CPP-ACP (PI: 32.7%) and without CPP-ACP (PII: 33.5%) compared to the salivary effect without stimulation (PIII: 39.8%) (p < 0.05). There was no difference between PI and PII (p > 0.05). The results suggest that the use of chewing gum immediately before an erosive demineralization can diminish enamel hardness loss. However, the presence of CPP-ACP in the chewing gum cannot enhance this protective effect.

Assessment of White Spot Lesions and In-Vivo Evaluation of the Effect of CPP-ACP on White Spot Lesions in Permanent Molars of Children

INTRODUCTION

As hindrance of remineralisation process occurs during orthodontic therapy resulting in decalcification of enamel because number of plaque retention sites increases due to banding and bonding of appliances to teeth.

AIM

The present analytic study was undertaken to assess the occurrence of white spot lesions in permanent molars of children with and without orthodontic therapy and to evaluate the effect of Casein PhosphoPeptide-Amorphous Calcium Phosphate (CPP-ACP) on white spot lesions in post-orthodontic patients in a given period of time.

MATERIALS AND METHODS

The study comprised of examination of 679 first permanent molars which were examined to assess the occurrence of smooth surface white spot lesions in children of 8 to 16 years age group. Group I comprised subjects without any orthodontic treatment and Group II comprised of subjects who had undergone orthodontic therapy. The sample size was calculated using the epi-info6 computer package. Treatment group included 20 post-orthodontic patients examined with at least one white spot lesion within the enamel who received remineralizing cream (GC Tooth Mousse, Recaldent, GC Corporation.) i.e., CPP-ACP cream two times a day for 12 consecutive weeks. Computerized image analysis method was taken to evaluate white spot lesions. These frequency and percentages were compared with chi-square test. For comparison of numeric data, paired t-test was used.

RESULTS

Of the total 278 (49.6%) first permanent molars showed occurrence of smooth surface white spot lesions out of 560 in Group I and 107 (89.9%) first permanent molars showed presence of white spot lesions out of 119 debanded first permanent molars of children examined in Group II. CPP-ACP therapy group showed reduction in severity of codes which was found to be highly significant after 12 weeks and eight weeks on gingival-third, p-value (<0.001) and significant after eight weeks and four weeks on middle-third according to ICDAS II criteria and computerized image analysis.

CONCLUSION

CPP-ACP therapy minimum for 12 weeks is highly recommended as post-orthodontic treatment need in management of smooth surface white spot lesions on teeth undergoing fixed orthodontic therapy according to the present study.

A simple, sensitive and non-destructive technique for characterizing bovine dental enamel erosion: attenuated total reflection Fourier transform infrared spectroscopy

Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Deionized water (control) and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth (110) were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 °C. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers' microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ν1, ν3 phosphate contour: the ratio of the height amplitude of ν3 PO4 to that of ν1 PO4 (Method 1) and the shift of the ν3 PO4 peak to a higher wavenumber (Method 2). The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy (P<0.001). Method 1 was the most sensitive to these changes, followed by surface hardness change measurements and Method 2. This study suggests that ATR-FTIR spectroscopy is potentially advantageous over the microhardness test as a simple, non-destructive, sensitive technique for the quantification of enamel erosion.

Monitoring Demineralization and Subsequent Remineralization of Human Teeth at the Dentin-Enamel Junction with Atomic Force Microscopy

Using atomic force microscopy, we monitored the nanoscale surface morphology of human teeth at the dentin-enamel junction after performing successive demineralization steps with an acidic soft drink. Subsequently, we studied the remineralization process with a paste containing calcium and phosphate ions. Repeated atomic force microscopy imaging of the same sample areas on the sample allowed us to draw detailed conclusions regarding the specific mechanism of the demineralization process and the subsequent remineralization process. The about 1-μm-deep grooves that are caused by the demineralization process were preferentially filled with deposited nanoparticles, leading to smoother enamel and dentine surfaces after 90 min exposure to the remineralizing agent. The deposited material is found to homogeneously cover the enamel and dentine surfaces in the same manner. The temporal evolution of the surface roughness indicates that the remineralization caused by the repair paste proceeds in two distinct successive phases.

Protective effect of casein phosphopeptide-amorphous calcium phosphate on enamel erosion: Atomic force microscopy studies

The aim of this study was to investigate the in vitro effect of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (GC Tooth Mousse- TM, GC Corporation, Tokyo, Japan) on preventing enamel erosion, by using Atomic Force Microscopy (AFM). 30 human incisors, were equally assigned to 6 groups: intact enamel, enamel + soft drink, enamel + TM, enamel + TM + soft drink, enamel + soft drink + TM, enamel + soft drink + TM + soft drink. Specimens were observed through atomic force microscopy (AFM). The most common topographical parameters were determined, such as the surface roughness (Rrms ). The use of soft drink on intact enamel has roughened the surface of the sample. The application of the CPP-ACP paste on non-treated enamel made the surface smoother. A significant decrease in roughness was seen after remineralization with CPP-ACP paste. Significant differences were recorded when comparing softened enamel with softened enamel remineralized with CPP-ACP paste. Comparing eroded enamel with demineralized/remineralized specimens, the application of a CPP-ACP paste leads to a significant reduction in roughness values. AFM images of enamel surface treated with CPP-ACP resulted in less morphological changes of the tooth substrate when compared with the only eroded enamel surface morphology; thus, indicating that CPP-ACP paste promoted remineralization. Specimens' surface roughness remained similar regardless that the protective agent is used before or after exposure to coke or between two demineralizing cycles. The results confirmed the effectiveness of the CPP-ACP paste on preventing enamel erosion produced by soft drinks.

Influence of Pastes Containing Casein Phosphopeptide-amorphous Calcium Phosphate on Surface of Demineralized Enamel

Purpose

The purpose of the study was to evaluate the surface characteristics of demineralized enamel after treatment with pastes containing casein phosphopeptide–amorphous calcium phosphate (CPP-ACP) or casein phosphopeptide–amorphous calcium fluoride phosphate (CPP-ACFP) and to compare their efficacy with that of 0.05% NaF.

Methods

Following formation of the artificial carious lesion, enamel slabs were divided into 4 groups (CPP-ACP, CPP-ACFP, 0.05% NaF and control) and submitted to a chemical caries model. Remineralization potential was examined using scanning electron microscope, energy-dispersive spectroscopy (EDS) and microhardness test. Scanning electron microphotographs were analyzed for area, minimal, maximal and mean diameter, perimeter, roundness and number of enamel defects and percentage of tooth surface affected by defects.

Results

Treatment with 0.05% NaF partly reduced the appearance of enamel defects when compared with irregular demineralized enamel. Treatment with CPP-ACP or CPP-ACFP resulted in occlusion of defects which produced more flattened enamel surface. Image analysis revealed reduction of the dimensions of the defects in the 3 experimental groups. Treatment with CPP-ACFP decreased the number of enamel defects when compared with demineralized enamel. The EDS analysis did not show differences in Ca/O, P/O and Ca/P ratios between the groups (P>0.05). Microhardness test revealed significant effects of CPP-ACP and CPP-ACFP (P<0.05).

Conclusions

Pastes containing CPP-ACP or CPP-ACFP showed potential to remineralize enamel surface lesions.

Three-dimensional profilometric assessment of early enamel erosion simulating gastric regurgitation

OBJECTIVES

A priority research area in minimal intervention dentistry is the characterization of the early stages of dental erosion. The aim of this in vitro study was to assess the effect of short, repetitive erosive challenges to human enamel over 2 min at pH 1.5 and 3.0 under conditions simulating gastric regurgitation.

METHODS

Enamel surfaces were subjected to erosive challenges at pH 1.5 (Group 1, n=10) and pH 3.0 (Group 2, n=9) for periods of 30s (stage 1), 60s (stage 2) and 120 s (stage 3). Quantitative changes were assessed longitudinally by measuring the 3D average surface roughness (Sa) values using 3D confocal microscopy. Qualitative micrographic assessment of surface changes was also conducted by using environmental scanning electron microscopy.

RESULTS

Linear mixed model analysis showed significant effects of the pH values (p<0.001) and the stages (p<0.001) on the observed Sa values. Post hoc tests showed significant increases in the Sa values between baseline and other stages in both groups (p<0.01). The mean Sa values also increased significantly from stage 1 to stage 2 in Group 1 (p<0.05). Micrographic analysis displayed severely etched enamel rods in Group 1, but only subtle changes in Group 2.

CONCLUSIONS

The complexity of the enamel surface is influenced by both acid concentration (pH value) and duration of acid exposure during early stages of erosion. Erosion occurring under conditions simulating GORD can be detected in its initial stages, opening up the possibilities of early diagnosis and management of this condition.

CLINICAL SIGNIFICANCE

Erosive tooth wear occurs progressively and insidiously, often creating complex treatment challenges. This emphasizes the need for early diagnosis and management in accordance with minimal intervention philosophy. Our findings provide a foundation for further research that could lead to the development of highly-sensitive clinical diagnostic tools and preventive strategies.

The effect of casein phosphopeptide-amorphous calcium phosphate paste and sodium fluoride mouthwash on the prevention of dentine erosion: An in vitro study

Aim:

The purpose was to compare the effect of 0.2% sodium fluoride mouthwash and casein phosphopeptide-amorphous calcium phosphate paste on prevention of dentin erosion.

Materials and Methods:

Buccal surfaces of 36 sound premolar teeth were ground flat and polished with abrasive discs. Half the polished surfaces were covered with tape to maintain a reference surface. Samples were randomly allocated into three groups. Group A was pretreated with tooth mousse (TM) 4 times a day for 5 days. Group B was pretreated with 0.2% sodium fluoride mouthwash 4 times a day for 5 days. Group C was considered as the control group with no pretreatment. In the next step, the samples were exposed to Coca-Cola 4 times a day for 3 days. After each erosive cycle, the samples were rinsed with deionized water and stored in artificial saliva. The surface loss was determined using profilometry.

Results:

The erosion in both Groups A and B was less than the control group. The surface loss in mouthwash group was significantly lower than in the control group. Erosion in TM group was more than the mouthwash group and less than the control group.

Conclusion:

Sodium fluoride mouthwash is more effective for prevention of dentin erosion.

Atomic force microscopic comparison of remineralization with casein-phosphopeptide amorphous calcium phosphate paste, acidulated phosphate fluoride gel and iron supplement in primary and permanent teeth: An in-vitro study

Context:

Demineralization of tooth by erosion is caused by frequent contact between the tooth surface and acids present in soft drinks.

Aim:

The present study objective was to evaluate the remineralization potential of casein-phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste, 1.23% acidulated phosphate fluoride (APF) gel and iron supplement on dental erosion by soft drinks in human primary and permanent enamel using atomic force microscopy (AFM).

Materials and Methods:

Specimens were made from extracted 15 primary and 15 permanent teeth which were randomly divided into three treatment groups: CPP-ACP paste, APF gel and iron supplement. AFM was used for baseline readings followed by demineralization and remineralization cycle.

Results and Statistics:

Almost all group of samples showed remineralization that is a reduction in surface roughness which was higher with CPP-ACP paste. Statistical analysis was performed using by one-way ANOVA and Mann-Whitney U-test with P < 0.05.

Conclusions:

It can be concluded that the application of CPP-ACP paste is effective on preventing dental erosion from soft drinks.

In vitro effect of calcium nanophosphate and high-concentrated fluoride agents on enamel erosion: an AFM study

BACKGROUND

Calcium nanophosphate paste can provide ions to remineralize enamel. There are, however, no data available about the remineralizing effect of this paste on the prevention of enamel erosion, when compared with highly concentrated fluoride agents.

AIM

To analyze the effect of calcium nanophosphate paste, fluoride gel, and varnish to protect against enamel erosion using surface Knoop hardness (KNH) and atomic force microscopy (AFM).

DESIGN

Forty enamel blocks (4 × 4 mm) of third molars were used for 4 groups (n = 10): 1.23% fluoride gel (Fluorgel-DFL(®) ); calcium nanophosphate paste (Desensibilize NanoP-FGM(®) ); fluoride varnish (Duraphat-Colgate(®) ) and control (without agent). The specimens were immersed in cola drink for 5 min and 2 h in artificial saliva, 4× per day for 5 days. The agents were applied before the first erosive cycle. KNH values were obtained before and after the erosive challenge. The surface morphology was evaluated by AFM. anova, Tukey's, and T-Student tests were applied.

RESULTS

After erosion, no significant difference was found for KNH among gel, nanophosphate, and varnish groups; however, they showed higher KNH than control group. Gel and nanophosphate paste showed a protective layer formation on enamel surface by AFM.

CONCLUSIONS

The calcium nanophosphate paste showed similar protection against enamel erosion compared with high-concentrated fluoride agents, even containing lower fluoride concentration.

The role of different toothpastes on preventing dentin erosion: an SEM and AFM study®

The aim of the present in vitro study was the evaluation of new formulation toothpastes on preventing dentin erosion produced by a soft drink (Coca Cola®), using atomic force microscopy (AFM) and scanning electron microscopy (SEM). Fifty dentin specimens were divided in treatment and control halves and were than assigned to 5 groups of 10 specimens each: group 1a: intact dentin, group 1b: dentin + soft drink, group 2a: intact dentin + Biorepair Plus-Sensitive Teeth®, group 2b: dentin + soft drink + Biorepair Plus-Sensitive Teeth®, group 3a: intact dentin + Biorepair Plus-Total Protection®, group 3b: dentin + soft drink + Biorepair Plus-Total Protection®, group 4a: intact dentin + Sensodyne Repair & Protect®, group 4b: dentin + soft drink + Sensodyne Repair & Protect®, group 5a: intact dentin + Colgate Sensitive Pro Relief®, group 5b: dentin + soft drink + Colgate Sensitive Pro Relief®. The surface of each specimen was imaged by AFM and SEM. Comparing specimens of group a and b (no demineralization and demineralization), a statistically significant difference (p < 0.01) in Rrms values was registered. Comparing b groups, all the analyzed toothpastes tended to remineralize the dentine surface in different extent. Biorepair Plus-Total Protection® and Sensodyne Repair & Protect® provided higher protective effect against dentin demineralization.

Effect of tricalcium silicate (Ca(3)SiO(5)) bioactive material on reducing enamel demineralization: an in vitro pH-cycling study

OBJECTIVES

The aim of this study was to investigate the effect of Ca(3)SiO(5) on reducing enamel demineralization under pH-cycling conditions.

METHODS

Forty bovine enamel samples were treated under four conditions: group 1, double distilled water (negative control); group 2, 1000 ppm F (as NaF, positive control); group 3, Ca(3)SiO(5) slurry; and group 4, Ca(3)SiO(5)-F slurry (Ca(3)SiO(5) with 1000 ppm F aq.). All the specimens were treated with treatment materials 4 times each day. Samples in groups 1 and 2 were soaked in test solutions for 2 min and samples in groups 3 and 4 were painted in treatment slurry for 2 min. At times between treatments, they were immersed in citric acid solution 3 times a day and 15 s each time. All the procedures were repeated for 7 days. Knoop microhardness, scanning electron microscopy (SEM), X-ray diffraction (XRD) and atom force microscopy (AFM) were used to examine samples.

RESULTS

After treatment for 7 days, enamels in all the groups were significantly softened. The extents of microhardness reduction were 52.3%, 28.5%, 28.5% and 20.2% for groups 1, 2, 3 and 4, respectively. Samples in the negative control group showed a typical acid etched pattern while enamels in other groups were relatively compact. There was no significant difference between samples treated with Ca(3)SiO(5) and F. The combination of Ca(3)SiO(5) with F showed the best effect on reducing enamel demineralization.

CONCLUSIONS

Ca(3)SiO(5) is an effective material against enamel demineralization alone but in combination with F a better anti-demineralization effect may be obtained.

Biofunctional properties of caseinophosphopeptides in the oral cavity

Caseinophosphopeptides (CPPs), bioactive peptides released from caseins, have the ability to enhance bivalent mineral solubility. This is relevant to numerous biological functions in the oral cavity (promotion of tooth enamel remineralisation, prevention of demineralisation and buffering of plaque pH). Therefore, CPPs may play a positive role as prophylactic agents for caries, enamel erosion and regression of white spot lesions. Most in vitro and in situ studies demonstrate strong evidence for the bioactivity of CPPs in the oral cavity. Nevertheless, relatively little is known concerning their use as adjuvants for oral health and more particularly regarding their long-term effects on oral health.

Impact of two toothpastes on repairing enamel erosion produced by a soft drink: an AFM in vitro study

OBJECTIVES

The aim of the present in vitro study was the evaluation of two toothpastes (Sensodyne Pronamel and Biorepair Plus on repairing enamel erosion produced by a soft drink (Coca Cola), using Atomic Force Microscopy (AFM).

METHODS

Fifty extracted human central incisors free of caries were selected and divided in a treatment and a control half; they were kept in artificial saliva during whole experimentation. The treatment halves were divided into five groups; group 1: demineralization with soft drink; group 2: demineralization with soft drink + Pronamel; group 3: demineralization with soft drink + Biorepair Plus; group 4: intact enamel + Pronamel; group 5: intact enamel + Biorepair Plus. Specimen demineralization was carried on in 4 intervals of 2 min. In groups 2, 3, 4, and 5 the toothpastes were applied for 3 min at 0, 8, 24 and 36 h. The surface of each specimen was imaged by AFM and R(rms), root-mean-square roughness, and Maximum Depth of the cavities were registered.

RESULTS

Amongst treatment specimens of groups 1, 2, and 3 a statistically significant difference (P<0.01) in R(rms) and Maximum Depth values was registered: the toothpastes reduced enamel demineralization. No statistical differences in R(rms) values were registered between the two toothpastes.

CONCLUSIONS

The toothpastes tested (Pronamel and BioRepair Plus) offer a degree of protection from erosive drinks.