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

A comparison of conventional sodium fluoride varnish and nano-sodium fluoride varnish regarding enamel microhardness of deciduous teeth: an in-vitro study

INTRODUCTION

Dental caries is the most common chronic disease worldwide, and various forms of fluoride are considered useful preventive tools. The production of nanoscale materials can significantly improve their mechanical and chemical properties. The present study compared the microhardness of primary tooth enamel after applying sodium fluoride varnish (conventional) and nano-sodium fluoride varnish.

MATERIALS AND METHODS

Sixty-eight sound canine teeth were selected in this experimental study. The teeth were mounted so that the buccal surface was exposed. A 3 × 3 mm square was obtained on the buccal surface of the crown of each tooth. Enamel surfaces were polished using sandpaper in the presence of water as a coolant. The samples were randomly divided into four groups (n = 17): G1, conventional 5% NaF; G2, 1% nano-NaF; G3, 5% nano-NaF; G4, control. The initial microhardness was measured. Before surface treatment with different fluoride compounds, the samples were placed in a demineralizing solution for two days, and the microhardness of all the samples was re-measured. Then G1, G2, and G3 were treated with the fluoride type specified for each group, and G4 was treated as a control (without treatment). Finally, pH cycling was applied, and the microhardness was measured again. Data were analyzed with SPSS 20, using Repeated measure ANOVA and post-hoc Tukey tests. P < 0.05 was considered significant.

RESULTS

Repeated measure ANOVA showed that microharness of G1, G2, G3, and G4 was statistically significant different. Tukey tests showed that the microhardness of G1, G2, and G3 were not significantly different. However, these three groups exhibited significantly more microhardness than the control group (P = 0.024, P = 0.027, and P = 0.010).

CONCLUSION

There was no significant differences in enamel microhardness of deciduous teeth between conventional 5% NaF,1% nano-NaF and 5% nano-NaF.

Remineralization potential of apacider gel on enamel and cementum surrounding margin of ceramic restoration

Background

Modern management of carious lesions has been targeted upon using remineralizing agents. This study investigated the remineralization potential of apacider gel (AG) and casein phosphopeptide-amorphous calcium fluoride phosphate (CA) on enamel and cementum around the cavosurface area of the ceramic margin.

Material and Methods

Seventy-five extracted human mandibular molars were sectioned at 0.8 mm above and below the cemento-enamel junction (CEJ) to remove the CEJ portions and replaced them with glass ceramic disks by bonding them to the crown and root portions with resin cement. The enamel and cementum area of 4x4 mm2 surrounding ceramic was demineralized with Carbopol-907. The demineralized surfaces were treated with either AG or CA, while one group was left with no treatment (NT) and served as control. Vickers microhardness was determined before-, after demineralization, and after remineralization. The percentage of hardness recovery (%HR), and remineralization potential (%RP) were analyzed with ANOVA and Bonferroni's test (α=0.05). Polarized light microscopy (PLM) was assessed for lesion depth. Scanning electron microscopy (SEM) was investigated for surface alterations.

Results

Significant differences in remineralization were found upon various remineralizing agents compared to NT for both enamel and cementum (p<0.05). No significant difference in %HR and %RP was observed between AG and CA (p>0.05). However, AG signified greater decrease in lesion depth and better improvement in surface characteristics for both enamel and cementum than CA.

Conclusions

AG possesses comparable remineralization ability to CA. However, decreasing in carious lesion depth was evinced with using AG more than CA. AG was recommended as a potential remineralization material for handling initial caries for both enamel and cementum. Key words:Apacider, artificial carious lesion, CCP-ACFP, remineralizationCare Team.

Antibacterial, Antibiofilm, and Tooth Color Preservation Capacity of Magnesium Oxide Nanoparticles Varnish (in vitro Study)

Purpose

Antibacterial and antibiofilm properties of magnesium oxide nanoparticles (MgONPs) mixture assessed against Streptococcus mutans (S. mutans), in addition to examining MgONPs varnish impact on the preservation of the tooth color and inhibition of methylene blue diffusion to the enamel.

Methods

MgONPs mixture was prepared in deionized water (DW), absolute ethanol (E), and rosin with ethanol (RE), named varnish. The antibacterial and antibiofilm capacities of MgONPs mixtures were tested by agar well diffusion, colony-forming unit (CFU), and biofilm inhibition microtiter methods in triplicate and compared to sodium fluoride varnish (NaF) and chlorhexidine mouthwash (ChX). A spectrophotometer was used to record basic tooth color. The artificial demineralization was initiated for 96 h. Then, experimental materials were applied to the corresponding group, and 10-day pH cycles proceeded. Then, the color was recorded in the same ambient environment. The methylene blue diffusion was evaluated by staining the samples for 24 h. After that, the diffusion test was calculated by a digital camera attached to the stereomicroscope.

Results

The agar well diffusion test expressed a significant inhibition zone with all MgONPs mixtures (p = 0.000), and maximum inhibition zone diameter associated with MgONPs-RE. The same finding was observed in the CFU test. Additionally, 2.5%, 5%, and 10% MgONPs-RE varnish showed strong biofilm inhibition capacity (p = 0.039) compared to NaF and ChX groups that inhibit biofilm formation moderately (p = 0.003). The study shows that the 5% MgONPs-RE varnish maintains basic tooth color with minimal methylene blue diffusion compared to NaF varnish (p = 0.00).

Conclusion

Evaluating MgONPs as a mixture revealed antibacterial and antibiofilm capacity against S. mutans with a higher effect of MgONPs-RE varnish. Also, examining the topical effect of MgONPs-RE varnish on the preservation of the tooth color after pH cycle challenges and methylene blue diffusion to enamel confirmed the high performance of MgONPs-RE varnish at 5%.

Comparative Evaluation of Zwitterionic Material, Self-assembling Peptide, and Bioactive Glass Incorporated with MI Varnish for Fluoride, Calcium, and Phosphorus Ion Release, Enamel Remineralization, and Microhardness

Background

White spot lesions occur when the pathogenic bacteria have broken through the enamel layer. White spot lesions (WSLs) can be treated using a complex approach. The most crucial step is to stop demineralization and biofilm formation and use assorted strategies for remineralization of lesions, thinning, microabrasion, erosion infiltration, adhesive composite resin restorations, and the bonded facets.

Aim

To evaluate and compare the fluoride, calcium, and phosphorus ion release, remineralizing efficacy, and microhardness of zwitterionic material, self-assembling peptide, and bioactive glass (BGA) incorporated with MI Varnish.

Materials and methods

The original study was conducted on 60 extracted premolars; the sample size calculated was 10 per group. All samples were divided into four groups-group A, MI Varnish (control), group B, MI Varnish + zwitterionic material, group C, MI Varnish + self-assembling peptide, and group D, MI Varnish + BGA. All these groups were further evaluated and compared for fluoride, calcium, and phorphorus ion release, remineralizing efficacy, and surface microhardness (SMH).

Results

Zwitterionic material, when incorporated with MI Varnish showed high fluoride and calcium ion release and high remineralizing efficacy under polarized light microscopy (PLM). BGA, when incorporated with MI Varnish showed high phosphorus ion release and higher values in the evaluation of SMH, followed by zwitterionic material and self-assembling peptide.

Conclusion

MI varnish alone had remineralizing properties of WSLs, but when novel materials like zwitterionic ion, self-assembling peptide, and BGA are incorporated, its efficacy increases. Among all zwitterionic ions showed superior results for fluoride and calcium ion release and remineralization and BGA for phosphorus ion release and SMH.

How to cite this article

Patil SV, Gugwad SC, Devendrappa SN, et al. Comparative Evaluation of Zwitterionic Material, Self-assembling Peptide, and Bioactive Glass Incorporated with MI Varnish for Fluoride, Calcium, and Phosphorus Ion Release, Enamel Remineralization, and Microhardness. Int J Clin Pediatr Dent 2024;17(S-1):S37-S42.

Remineralization potential of apacider mangosteen adhesive pastes on artificial carious lesions

Background/purpose

Attention to caries administration has altered toward an early finding of lesions and targeted to noninvasive management with a remineralizing agent. This study compared the remineralization potential of apacider mangosteen adhesive pastes (AMAP), 500-ppm fluoride toothpaste (FT500), and 1000-ppm fluoride toothpaste (FT1000) on artificial caries.

Materials and methods

Artificial caries were generated to enamel of eighty extracted human premolars. The specimens were allocated to four groups and subjected to pH-cycling with the application of testing agents (2 min each, for 10 days): (1) AMAP, dairy, (2) FT500, twice a day, (3) FT1000, twice a day, and (4) no treatment (NT). The surface microhardness was determined before demineralization, after demineralization, and after application of pH-cycling. The hardness, percent of hardness recovery (%HR), and percent of remineralization potential (%RP) were analyzed with ANOVA and Bonferroni's test (α = 0.05). Polarized light microscopy (PLM) was assessed for lesion depth.

Results

Significant differences in remineralization were observed upon various agents compared to NT (P < 0.05). A significant difference in remineralization was found among AMAP, FT1000, and FT500 (P < 0.05). No significant difference in %HR and %RP was observed between AMAP and FT1000 (P > 0.05). PLM signified greater decrease in depth for AMAP, compared to FT1000 and FT500, but no depth reduction for NT.

Conclusion

AMAP possesses comparable remineralization ability to FT1000. However, decreasing in depth of carious lesions was evinced with using AMAP more than FT1000 and FT500. AMAP was recommended as a potential remineralization material for handling initial caries.

Combined Effect of a Bioinspired Self-Assembling Peptide and Fluoride Varnish on Remineralisation of Artificial Early Enamel Caries Lesion: An in vitro Study

INTRODUCTION

This study aimed to investigate the remineralisation effect of combined use of a bioinspired self-assembling peptide (P26) and fluoride varnish on artificial early enamel caries lesions.

METHODS

Bovine enamel blocks with artificial early enamel caries lesions were prepared. The blocks were randomly allocated to four experimental groups to receive the following treatments: A = P26 + fluoride varnish, B = P26, C = fluoride varnish, and D. distilled water (negative control). The treated blocks were subjected to pH cycling. Enamel blocks were collected at time points of 7 days (d7) and 21 days (d21). The mineral gain, elemental analysis and crystal characteristics of the caries lesion were assessed by micro-computed tomography, scanning electron microscopy with energy dispersive X-ray and X-ray diffraction (XRD), respectively.

RESULTS

The mean ± standard deviation of mineral gain of group A to D were 17.4 ± 4.2%, 10.7 ± 2.2%, 10.1 ± 1.2%, and 6.8 ± 0.5% at d7, respectively, and 15.2 ± 2.6%, 8.7 ± 3.1%, 9.7 ± 1.2%, and 7.8 ± 2.3% at d21, respectively. A significant higher mineral gain was observed in group A when compared to other groups at both d7 and d21 (p < 0.05). The calcium-to-phosphate ratio remained consistent across all groups, ranging between 1.2 and 1.4. XRD analysis indicated that crystal composition on the surfaces was apatite for all groups.

CONCLUSION

In conclusion, the present study provided a first indication of better remineralisation effects of the combined use of the bioinspired self-assembling peptide P26 and fluoride varnish compared to the effects of the respective individual uses of P26 or fluoride varnish.

The Remineralization Effect of Calcium Glycerophosphate in Fluoride Mouth Rinse on Demineralized Primary Enamel: An in vitro Study

Aim

To evaluate the remineralization effect of a fluoride mouth rinse containing calcium glycerophosphate in fluoride mouth rinse based on the surface microhardness of demineralized primary enamel.

Materials and Methods

40 sound primary incisors were placed into self-curing acrylic resin and subjected to a demineralizing solution for 5 days, resulting in the formation of artificial caries. The teeth were categorized into four groups (n = 10): group I artificial saliva, group II sodium fluoride, group III sodium fluoride + sodium monofluorophosphate, and group IV sodium monofluorophosphate + calcium glycerophosphate. The specimens received a pH cycling procedure and were submerged twice in their assigned groups for 7 days. The baseline, after demineralization, and after remineralization surface microhardness values were determined. One-way analysis of variance (ANOVA) was used to analyze the mean surface microhardness between groups and one-way repeated measures ANOVA for the mean surface microhardness within each group and Bonferroni's for multiple comparisons at 95% confidence level. The percentage recovery surface microhardness was determined by calculating the average surface microhardness.

Results

After demineralization, the mean surface microhardness in all groups significantly decreased. After remineralization, group I had the lowest surface microhardness values and the percentage recovery surface microhardness (P value < 0.001), and group IV had the highest surface microhardness values and the percentage recovery surface microhardness (P value < 0.001). No significant difference was found between groups II and III (P value = 0.365).

Conclusions

Fluoride mouth rinse containing calcium glycerophosphate has a remineralization effect on demineralized primary enamel.

Effect of polydopamine and fluoride ion coating on dental enamel remineralization: an in vitro study

BACKGROUND

Fluoride treatment is one of the most effective dental caries prevention methods. To continuously prevent dental caries, stably immobilizing the fluoride on the tooth enamel is highly desirable. This study aimed to evaluate the remineralization of tooth enamels by one-pot coating using polydopamine and fluoride ions.

METHODS

To prepare the enamel specimens for polydopamine- and fluoride ion-coating, they were treated with polydopamine- and fluoride-containing gels. The enamel specimens were collected from human molars in a blind manner (n = 100) and were randomized into five treatment groups (n = 20, each): 1) untreated, 2) polydopamine-coated, 3) fluoride-containing gel-treated, 4) F varnish-treated, and 5) polydopamine- and fluoride ion-coated enamels. Vickers hardness number (VHN), morphology, and fluoride contents of the specimens were measured before and after the pH-cycling regimen.

RESULTS

Polydopamine- and fluoride ion-coated enamels showed the highest fluoride content and lowest VHN reduction among the samples. The fluoride content of the polydopamine/fluoride ion (PD/F)-coated enamel was increased to 182 ± 6.6%, which was far higher than that of the uncoated enamel (112.3 ± 32.8%, P < 0.05). The changes in the VHN values (ΔVHN) of PD/F-coated enamel substrates showed a slight reduction in the VHN (-3.6%, P < 0.05), which was far lower than that in the control group (-18.9%, P < 0.05). In addition, scanning electron microscopy clearly supported the effect of polydopamine- and fluoride ion-coatings on the remineralization of enamel specimens.

CONCLUSION

Our findings suggest that one-pot treatments with polydopamine and fluoride ions could significantly enhance remineralization by inhibiting enamel demineralization through the prolonged retention of fluoride ions.

Qualitative and Quantitative Profiling of Enamel Remineralizing Potential of Fluoride Varnishes Incorporating Bioactive Glass, Dicalcium Phosphate Dihydrate, and Modified MTA: A Raman Spectroscopic Study

Aim

To evaluate and compare for remineralization potential of enamel at three different time intervals using commercially available MI Varnish and Duraflor Halo varnish [5% sodium fluoride (NaF) varnish] incorporating bioactive glass, dicalcium phosphate dihydrate (DCPD), and biomimetically modified mineral trioxide aggregate (MTA).

Materials and methods

For the study, a buccolingual division into equal halves was done for 64 decoronated premolar crowns. Among these 64 crowns, we mounted 32 in acrylic discs to be used for microhardness and induced white spot lesions (WSLs) measuring 5 × 5 mm on the exposed enamel surface. These samples were divided into four groups of 24 each depending upon the varnish used. Varnish application was done, followed by immersion of these samples for 24 hours in artificial saliva, followed by peeling off of varnish. A pH cycling of 28 days was done after the varnish application before assessing the remineralization of the samples. Evaluation of all these samples was done at three different time intervals, baseline, after demineralization, and post remineralization for microhardness on the enamel surface. Raman spectroscopy was utilized for the measurement of phosphate (P) ion release. Sectioning of these samples to a thickness of 100 µm approximately was done to be viewed under a polarized light microscope.

Results

Bioactive glass incorporated varnish showed the highest microhardness values, mineral content levels, and least depth of lesion posttreatment.

Conclusion

All the experimental varnish showed significant remineralizing potential with the best potency seen with bioactive glass incorporated varnish.

Clinical significance

The nonfluoride agents can be appropriately used in 2 wt% amount to augment the benefits of fluoride.

How to cite this article

Hardikar AS, Gaonkar NN, Devendrappa SN, et al. Qualitative and Quantitative Profiling of Enamel Remineralizing Potential of Fluoride Varnishes incorporating Bioactive Glass, Dicalcium Phosphate Dihydrate, and modified MTA: A Raman Spectroscopic Study. Int J Clin Pediatr Dent 2023;16(2):363-370.

Comparative evaluation of prevention of demineralization of artificial enamel caries treated with two fluoride varnishes and 38% SDF in primary teeth: an in vitro study

BACKGROUND

This study aimed to compare the effect of Clinpro™ White varnish containing 5% sodium fluoride (NaF) and functionalized tricalcium phosphate, MI varnish containing 5% NaF and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and 38% Silver diamine fluoride (SDF) in preventing demineralization of treated white spot lesions (WSLs) in enamel of primary teeth.

METHODS

Forty-eight primary molars with artificial WSLs were allocated into four groups as follows: Group 1: Clinpro white varnish, Group 2: MI varnish, Group 3: SDF, and Group 4: control (no treatment). The three surface treatments were applied for 24 h and then enamel specimens were subjected to pH cycling. Thereafter, the mineral content of specimens was evaluated by Energy Dispersive X-ray Spectrometer and the lesion depth was assessed via Polarized Light Microscope. One-way ANOVA followed by Tukey's post hoc test were used at p ≤ 0.05 to identify significant differences.

RESULTS

Insignificant difference in mineral content was observed among treatment groups. Treatment groups exhibited significantly higher mineral content compared to control except for Fluoride (F). MI varnish showed the highest mean calcium (Ca) ion content (66.57 ± 0.63), and Ca/P (2.19 ± 0.11), followed by Clinpro white varnish, and SDF. MI varnish also displayed the highest phosphate (P) ion content (31.46 ± 0.56), followed by SDF (30.93 ± 1.02), and Clinpro white varnish (30.53 ± 2.19). Fluoride content was highest in SDF (0.93 ± 1.18), followed by MI (0.89 ± 0.34) and Clinpro (0.66 ± 0.68) varnishes. Significant difference in lesion depth was observed among all groups (p < 0.001). The lowest mean lesion depth (µm) was found in MI varnish (226.23 ± 44.25) which was significantly lower than Clinpro white varnish (285.43 ± 44.70), SDF (293.32 ± 46.82), and control (576.69 ± 42.66). Insignificant difference in lesion depth was found between SDF and Clinpro varnish.

CONCLUSIONS

In primary teeth, WSLs treated with MI varnish displayed better resistance to demineralization compared to WSLs treated with Clinpro white varnish and SDF.

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.

Effect of Fluoride-based Varnishes with Added Calcium and Phosphate on Microhardness of Esthetic Restorative Materials: An In Vitro Study

Background and objectives

Fluoride varnishes are being used to prevent caries in children. The high concentration of fluoride in varnishes apart from caries prevention may cause changes in surface properties of esthetic restorations. The study aims to evaluate and compare the effect of four commercially available fluoride varnishes with added calcium and phosphate on microhardness of three esthetic materials namely conventional GIC (Fuji II), high viscosity GIC (Fuji IX), and nanocomposite (Filtek Z350).

Materials and methods

A total of 28 pellets were made of each material and stored in distilled water at 37 °C for 48 hours. The microhardness of the pellets was tested which served as a baseline. These were then randomly divided into four subgroups. In one subgroup Profluorid varnish was applied, second subgroup MI varnish was applied, third subgroup Embrace varnish was applied, and in the fourth subgroup Enamel Pro varnish was applied as per protocol. Thereafter, all the pellets were subjected to microhardness testing (load = 100 g for 15 seconds).

Results

The fluoride varnishes increased the microhardness of conventional GIC (Fuji II) whereas in case of high viscosity GIC (Fuji IX) the application of varnishes reduced the microhardness. In case of nanocomposite restorative material (Filtek Z350) only Profluorid varnish increased its microhardness.

Conclusion

Fluoride varnish and calcium-phosphate containing fluoride varnish effect on the microhardness of restorative material is material dependent. So, the choice of fluoride varnish with or without proprietary additives depends on the nature and composition of the restorative material.

How to cite this article

Shetty RS, Bhat SS, HK Sundeep, et al. Effect of Fluoride-based Varnishes with Added Calcium and Phosphate on Microhardness of Esthetic Restorative Materials: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(2):187-193.

Efficacy of CPP-ACP fluoride varnish applied with and without acid etching in preventing enamel demineralization compared to light-curable fluoride varnish

Objectives

To compare efficacy of casein phosphopeptide (CPP)–amorphous calcium phosphate (ACP) fluoride varnish and light-curable resin modified glass ionomer fluoride varnish (FV) in preventing white spot lesions and evaluating acid etching prior to CPP-ACPFV application on its efficacy.

Materials and Methods

Molars and premolars were transected and halves divided into four groups (n = 18/group): (1) resin-modified glass ionomer FV: etched and Clinpro-XT varnish (3M ESPE, Pymble, New South Wales, Australia) application; (2) CPP-ACPFV: MI varnish (GC America, Alsip, IL) application; (3) Etch+CPP-ACPFV: etched and MI varnish application; (4) Control: etched and no surface treatment. To simulate 12 weeks in an intraoral environment, samples were subjected to thermocycling, brushing, and pH cycling. Enamel surface microhardness was evaluated at baseline and after the simulated 12 weeks. Representative samples were also assessed using scanning electron microscopy (SEM).

Results

At baseline there was no significant difference in microhardness among groups. After the simulated 12 weeks, all groups showed significant within-group differences (P &lt; .001). Control showed the highest percentage loss of surface microhardness (89%), followed by CPP-ACPFV (58%), RMGIFV (51%), and Etch+CPP-ACPFV (24%). The control group had a significant decrease in microhardness compared to all experimental groups (P &lt; .001). No difference was found between the RMGIFV and CPP-ACPFV varnish groups. The Etch+CPP-ACPFV group had significantly less decrease in microhardness compared to the RMGIFV (P &lt; .001) and CPP-ACPFV groups (P &lt; .001). With SEM, control samples showed signs of enamel surface damage, while experimental groups showed spherical particles on a relatively intact surface.

Conclusions

RMGIFV and CPP-ACPFV are effective in reducing enamel demineralization. Acid etching the enamel surface prior to CPP-ACPFV varnish application increased its efficacy.

How different time intervals between repeated applications of CPP-ACP fluoride varnish effect smooth surface enamel demineralization?

OBJECTIVES

To evaluate the preventive effects of different time intervals between repeated applications of the CPP-ACP fluoride varnish on enamel demineralization.

METHODS

Human teeth were sectioned and randomly allocated to three groups: 4-week, 6-week, and 12-week (N = 22/group). Baseline images of the enamel surfaces were obtained using the FluoreCam recording the area, intensity, and impact of baseline enamel demineralization. All groups received fluoride varnish applications at the beginning of the experiment. The varnish was reapplied every 4 or 6 weeks in the 4-week and 6-week groups, respectively. Following each application, the groups underwent thermo-cycling, tooth brushing and pH cycling to simulate the time effect. After 12 weeks, the enamel surfaces were reimaged using the FluoreCam. Within and between-group differences in the area, intensity and impact of demineralization were evaluated.

RESULTS

At baseline, there were no significant between-group differences for area, intensity, or impact. Statistically significant (p<0.001) enamel demineralization occurred over time within each group. There were significant between-group differences in the changes that occurred in area (P = 0.004), impact (P = 0.022), but not intensity. The 12-week had significantly larger areas of demineralization than the 6-week (P = 0.041) and 4-week (P = 0.001) groups. Changes in impact was significantly (P = 0.007) greater in the 12-week group than 4-week group, but not greater than the 6-week group. There were no statistically significant differences between 4- and 6-week groups in the changes of area, intensity, or impact.

CONCLUSION

Reapplication of the CPP-ACP fluoride varnish every 4-6 weeks, is more effective in reducing enamel demineralization compared to every 12 weeks.

Efficacy of MI Paste® on Bleaching-Related Sensitivity: Randomized Clinical Trial

Background

To evaluate the effectiveness of MI Paste® in reducing sensitivity associated with vital tooth bleaching.

Methods

This randomized controlled split-mouth clinical trial included 45 subjects that were randomly divided into two groups. In Group 1, the maxillary arch was the control arch (only bleaching), while the mandibular arch was the intervention arch (bleaching and MI Paste®). In Group 2, the mandibular arch was the control arch (only bleaching), while the maxillary arch was the intervention arch (bleaching and MI Paste®). Subjects started with the control arch and then switched to the intervention arch after two weeks. Subjects were instructed to use MI Paste® in a custom tray for 5 minutes, wait for 1 hour, and then bleach overnight using a different tray. Sensitivity was measured using both a thermal sensitivity test and a daily log of sensitivity for 14 days. Shade was evaluated using a colorimeter and a shade guide.

Results

Immediately after treatment, the thermal test sensitivity scores for the arches bleached without MI Paste® were greater than those with MI Paste® (p=0.011). Arches not receiving the MI Paste® treatment showed significantly higher VAS sensitivity scores during the 14-day period of bleaching (p=0.002). The mean score for the 14-day period was 37.9 for the arches not treated with MI Paste® versus 27.5 for the treated arches. Both the intervention group and the control group showed significantly lighter shade relative to baseline (p < 0.001) with no significant difference between them (p=0.42).

Conclusion

MI Paste® significantly reduced the sensitivity associated with bleaching and did not interfere with shade change.

Effect of casein-phosphopeptide amorphous calcium phosphate and fluoride with/without erbium, chromium-doped yttrium, scandium, gallium, and garnet laser irradiation on enamel microhardness of permanent teeth

BACKGROUND

Laser therapy, along with the use of fluoridated compounds is a novel technique suggested for caries prevention. Casein phosphopeptide amorphous calcium phosphate (CPP-ACP) is another product suggested for this purpose. This study compared the effect of CPP-ACP and fluoride with/without Erbium, chromium-doped yttrium, scandium, gallium, and garnet laser irradiation on enamel microhardness of permanent teeth.

MATERIALS AND METHODS

This in vitro experimental study evaluated 35 extracted third molars. The teeth were decoronated, and the crowns were split into buccal and lingual halves. The samples were randomly divided into seven groups (n = 10) of GC Tooth Mousse, MI Paste Plus, laser, fluoride varnish, laser + GC Tooth Mousse, laser + MI Paste Plus, and laser + fluoride varnish. The baseline microhardness was measured before the intervention. After the intervention, the samples were kept in artificial saliva for 1 h and were then immersed in the demineralizing solution for 3 h followed by 21 h of immersion in the remineralizing solution for a total period of 12 days. Finally, the teeth were kept in the remineralizing solution for 2 more days. The secondary microhardness of the teeth was then measured. Data were analyzed using the Shapiro-Wilk test, two-way ANOVA, and Tukey's Honestly Significant Difference test.

RESULTS

The fluoride varnish (14.31%) and laser + fluoride varnish (18.79%) groups experienced minimum reduction in microhardness, while the GC Tooth Mousse group experienced maximum reduction in microhardness (91.64%) (P < 0.001). Laser irradiation before the application of remineralizing agents increased the microhardness only in laser + GC Tooth Mousse group (P < 0.001).

CONCLUSION

Fluoride varnish increased the enamel microhardness, while GC Tooth Mousse had no such effect. Laser therapy before the application of remineralizing agents did not significantly enhance enamel resistance to demineralization.

Fluoride release and remineralizing potential of varnishes in early caries lesions in primary teeth

This study evaluated the fluoride (F) release and remineralizing potential of varnishes containing sodium fluoride (5% NaF), 5% NaF with CPP-ACP and 5% NaF with TCP in early caries lesions in primary teeth. To determine the F release at 1, 4, 6, 24, 72, and 168 hr, strips were covered with the varnishes and immersed in purified water (n = 7). The varnishes and purified water (negative control) were applied on enamel blocks with early caries lesions (n = 16). Enamel blocks were stored in artificial saliva and submitted to a pH-cycling. The area of enamel hardness loss (ΔS) was analyzed by microhardness, lesion depth by polarized light microscopy (PLM) and the chemical analysis by Energy-dispersive X-ray spectroscopy. Data were submitted to Shapiro-Wilk, two-way and one-way ANOVA, Tukey and paired t-tests (α = 5%). All varnishes released F, but 5% NaF with CPP-ACP had the highest release at 4, 6, 24, and 72 hr (p < .05) followed by 5% NaF with TCP and 5% NaF. No significant difference in ΔS was observed among varnishes (5% NaF = 4,098.4 ± 1,407.9; 5% NaF with CPP-ACP = 4,164.0 ± 1,019.3; 5% NaF with TCP = 4,183.2 ± 1,527.2; p = .999), but all of them differed from the negative control group (6,757.8 ± 2,274.7; p < .001). Lesion depth was lower in varnishes groups compared to negative control (% reduction: 5% NaF = 41.8%, 5% NaF with CPP-ACP = 38.8%, and 5% NaF with TCP = 36.3%; p < .001). Similar Ca, P, and Ca/P ratio percentages among groups and F was not detected after the treatments. All fluoride varnishes showed potential to enhance remineralization of early caries lesions in primary teeth.

Evaluation of F, Ca, and P release and microhardness of eleven ion-leaching restorative materials and the recharge efficacy using a new Ca/P containing fluoride varnish

OBJECTIVES

The objectives of this study were to evaluate fluoride (F), calcium (Ca), and phosphate (P) release of ion-leaching restorative materials (ILMs), their recharge efficacy with a Ca/P-containing F varnish, and relative microhardness.

METHODS

Thirteen groups of materials were investigated. Cylindrical-shaped specimens were fabricated. Deionised water or lactic-acid solution were used as the storage media. Solutions were changed after 1d, 4d, 7d, and 14d of ion release and at the same periods after recharge with MI Varnish (7 -h storage). F, Ca, and P measurements were accomplished using a fluoride-ion selective electrode, atomic absorption spectrometry, and colourimetric method by spectrophotometer, respectively. Relative Vickers hardness was proceeded with similar specimens used in the F assay (4 periods). SEM/EDS was additionally performed. Statistical analyses were calculated in each parameter (p < 0.05).

RESULT

Hardness of several ILMs immediately increased after recharge. After 28d, Ketac Universal [a high-viscosity glass-ionomer cement (HVGIC)] showed the highest hardness similar to the resin composite control. Although 2 HVGICs (Zirconomer and Equia Forte Fil) ranked as first and second for F release/re-release, some HVGICs had inferior or comparable F capacity to RMGICs (Fuji VIII and Fuji II LC) and a resin-based (RB) ILM (Cention N). Cention N, Activa-Restorative (RB-ILM), and Zirconomer were the top-3 ranking for Ca release/re-release. Activa-Restorative showed the highest P release, whereas Cention N displayed the greatest recharge ability for P.

CONCLUSIONS

Zirconomer showed a versatile performance for ion-release/re-release, especially for F. Cention N had excellent capacity in relation to Ca release and recharge ability of Ca/P.

CLINICAL SIGNIFICANCE

With the F varnish recharge protocol, Zirconomer, Equia Forte, and Fuji VIII seems to have an ability to inhibit initial caries initiation. Cention N is a promising resin-based material that could be an alternative for high caries risk patients due to the high Ca release/recharge with acceptable F release.

Remineralization and fluoride uptake of white spot lesions under dental varnishes

INTRODUCTION

The aim of this study was to evaluate white spot lesion (WSL) remineralization and fluoride uptake by the application of fluoride varnishes directly onto artificial WSLs in vitro.

METHODS

MI varnish containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and 2.26% fluoride and Duraphat varnish containing 2.26% fluoride (no added calcium) were compared with a placebo varnish (no added calcium or fluoride). Two WSLs were prepared in enamel slabs and varnish applied to cover one of the two lesions. Each slab was immersed in artificial saliva for 14 days at 37°C. Mineral content was determined using transverse microradiography and fluoride uptake using electron probe microanalysis. The data were statistically analysed using a linear mixed model.

RESULTS

Both MI and Duraphat varnishes significantly remineralized the covered and uncovered WSLs when compared with the placebo varnish (P < 0.001). The WSLs covered with varnish showed greater remineralization than those uncovered. MI varnish produced the highest level of remineralization and significantly greater fluoride uptake (0.44 ± 0.08 wt%) compared with Duraphat (0.24 ± 0.03 wt%) and the placebo varnish (0.06 ± 0.05 wt%).

CONCLUSION

Varnish containing fluoride and CPP-ACP was superior to varnish containing fluoride alone in promoting WSL remineralization and fluoride uptake.

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

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

In Vitro Comparison of Fluoride, Magnesium, and Calcium Phosphate Materials on Prevention of White Spot Lesions around Orthodontic Brackets

One common negative side effect of orthodontic treatment with fixed appliances is the development of white spot lesions (WSLs) around brackets. This study is aimed at comparing the efficacy of various oral hygiene practices in preventing enamel demineralization around orthodontic brackets under similar in vitro conditions. The study included 90 extracted bovine incisors, which were randomized into six groups: fluoride toothpaste (FT), nonfluoride toothpaste (NFT), fluoride varnish plus fluoride toothpaste (FV+FT), CPP-ACP varnish plus fluoride toothpaste (CPP-ACP+FT), medical minerals gel plus nonfluoride toothpaste (MMG+NFT), and no intervention (control). All groups were subjected to demineralization and remineralization cycles. Visual appraisals were used to evaluate the changes in the enamel surface appearance at the beginning and end of the experiment. The changes in the demineralization degree were evaluated by measuring the Ca⁺² concentration in the demineralization solution at different time points. The majority of teeth in the CPP-ACP+FT group exhibited no shift in appearance, whereas in the other groups, a slight change in enamel translucency was observed. At all the time points, the Ca⁺² concentration in the demineralization solution in the CPP-ACP+FT group was the least among all other groups. At day 5, MMG+NFT's preventive efficacy was significantly higher than FV+FT's, but at days 10, 15, and 19, their efficacy was similar. However, at all the time points, MMG+NFT's efficacy was significantly higher than that of control, whereas FV+FT's efficacy was decreased at days 10, 15, and 19 and was close to the efficacy of control. To fight WSLs, early diagnosis was of great importance and examination of the tooth surface after air-drying for 5 s was recommended.

Evaluation of Change in Microhardness by Application of MI Varnish on Primary Tooth Enamel, Affected by Use of Frequently Prescribed Paediatric Syrups: An In Vitro Study

Introduction Dental erosion is considered as an irreversible progressive loss of tooth structure due to chemical dissolution by acids not of bacterial origin. Frequent intake of syrups can be an effective factor in tooth erosion when prescribed for illnesses. In the acidic environment, MI Varnish releases calcium, phosphate and fluoride from the covering layer and the teeth can be prevented from such acidic attacks from the erosive content of the syrups. Aim  To evaluate change in microhardness by application of MI Varnish on primary tooth enamel, affected by use of frequently prescribed paediatric syrups. Method  The effects of three paediatric syrups (Ibugesic Plus, Novamox, Becozinc H) and distilled water (control group) with different ingredients on primary tooth enamel were evaluated. Immersion cycles were applied three times a day for one minute. The measurements of the samples prepared were taken on 0 (baseline), third, fifthand seventh day. Microhardness was measured using a Vickers hardness tester. Then, those samples were coated with MI Varnish, and changes in microhardness were evaluated using the Vickers hardness tester after one week (14th day). The pH, titratable acidity and buffer capacity of the syrups were also evaluated. Results  There was a significant decrease in microhardness in all the syrups (p < 0.001) on days 3, 5, 7 and 14. Novamox syrup and distilled water (control group) were the least erosive on the primary tooth enamel and Becozinc H syrup being the most erosive on primary tooth enamel was seen. MI Varnish remineralized the enamel but not with any significant difference. Conclusion  In our findings, Novamox syrup showed the least erosion on primary tooth enamel compare to other syrups. Enamel microhardness was significantly reduced on all days after immersion in all syrups. Application of MI Varnish to enamel resisted erosion but was not significant. Paedodontists should be aware of the erosive potential of all the frequently prescribed syrups and stress on compliance with oral hygiene measures and application of varnishes releasing fluoride, calcium and phosphate on the tooth.

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

Background

Remineralization of incipient caries is one of the goals in dental health care ,especially in pediatric dentistry. The present study aimed at comparing the effects of MI varnish (3M (United states)) , Nano paste( FGM(Brezil) ), 5% sodium fluoride varnish) DuraphatColgate (united states) ) on remineralization of enamel lesions.

Material and Methods

In this in-vitrostudy, 60 intact human pre-molars, were randomly allocated to four groups of 15. Baseline surface microhardness in three points in the center of the polished area was measured. After two days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 under-went treatment with MI varnish, nano paste, 5% sodium fluoride varnish and then again microhardness was measured. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Bonfreni table was used.

Results

Duraphat varnish in comparison with control group, significantly increased surface microhardness and in comparison with Nano and MI paste varnish groups significant differences was shown between groups. (P< 0.05). MI paste varnish and Nano paste similary showed more increases in surface microhardness in comparison with Duraphat varnish and control groups (P≈1).

Conclusions

According to the results of this study, all three varnishes, Duraphat , MI paste and Nano paste increase the enamel surface microhardness and remineralization of incipient caries. MI paste and Nano paste compared to Duraphat Varnish, significantly showed more increases in enamel surface microhardness but Nano paste and MI paste were almost the same. Key words:CPP-ACP, Nano varnish, fluoride varnish, microhardness, demineralization, remineralization.

Remineralizing effect of commercial fluoride varnishes on artificial enamel lesions

The aim of this study was to evaluate soluble and insoluble fluoride concentrations in commercial varnishes, and their remineralization effect on artificial caries enamel lesions using surface and cross-sectional microhardness evaluations. Forty bovine enamel blocks were separated into four groups (n=10): control (no treatment), Enamelast (Ultradent Products), Duraphat (Colgate-Palmolive) and Clinpro White Varnish (3M ESPE). Surface enamel microhardness evaluations were obtained, artificial enamel caries lesions were developed by dynamic pH-cycling, and the varnishes were then applied every 6 days, after which the enamel blocks were submitted to dynamic remineralization by pH cycles. After removal of the varnishes, the enamel surfaces were reassessed for microhardness. The blocks were sectioned longitudinally, and cross-sectional microhardness measurements were performed at different surface depths (up to 300 μm depth). Polarized light microscopy images (PLMI) were made to analyze subsurface caries lesions. The fluoride concentration in whole (soluble and insoluble fluoride) and centrifuged (soluble fluoride) varnishes was determined using an extraction method with acetone. The data were analyzed to evaluate the surface microhardness, making adjustments for generalized linear models. There was a significant decrease in enamel surface microhardness after performing all the treatments (p<0.0001). Enamelast and Duraphat showed significantly higher enamel microhardness values than the control and the Clinpro groups (p = 0.0002). Microhardness loss percentage was significantly lower for Enamelast (p = 0.071; One-way ANOVA). PLMI showed that subsurface caries lesions were not remineralized with the varnish treatments. No significant differences in the in-depth microhardness levels (p = 0.7536; ANOVA) were observed among the treatments. Enamelast presented higher soluble and insoluble fluoride concentrations than the other varnishes (p < 0.0001; Kruskal-Wallis and Dunn tests). Enamelast and Duraphat varnishes promoted enamel surface remineralization, but no varnish remineralized the subsurface lesion body. Although insoluble and soluble fluoride concentration values did not correspond to those declared by the manufacturer, Enamelast presented higher fluoride concentration than the others.

Preventive effects of carbon dioxide laser and casein phosphopeptide amorphous calcium phosphate fluoride varnish on enamel demineralization: A comparative, in vitro study

AIM

The aim of the present study was to compare the effects of carbon dioxide (CO₂ ) laser and casein phosphopeptide amorphous calcium phosphate (CPP-ACP)fluoride varnish on enamel demineralization.

METHODS

Human teeth were randomly assigned to three groups. The enamel was treated with fluoride varnish, 10.6 μm CO₂ laser, or no treatment (control), followed by 9 days of pH cycling. Baseline and final FluoreCam images were used to quantify the area, intensity, and impact of demineralization; cross-sectional microhardness was used to measure the mechanical properties of the enamel.

RESULTS

There were statistically-significant changes in the area, intensity and impact of demineralization in the control and laser groups (P < 0.05), but not in the fluoride group. The control group showed a significantly greater area and impact of enamel demineralization compared to the fluoride group. The area of demineralization in the laser group was significantly greater than that of the fluoride group. Enamel demineralization of the laser and control groups was comparable. The fluoride group showed statistically-significant harder enamel than the control at 20, 40, and 60 μm depths; the laser group enamel was significantly harder than the control at 20 and 40 μm depths. The fluoride group showed statistically-significant harder enamel than the laser group at 20 μm depth.

CONCLUSIONS

CPP-ACP fluoride varnish is more effective than CO₂ in preventing enamel demineralization.

In Vitro Effect of Innovative Desensitizing Agents on Dentin Tubule Occlusion and Erosive Wear

Purpose:

The purpose of this study was to evaluate the effects of four in-office desensitizing products on dentin tubule occlusion and erosive wear.

Methods:

Dentin hypersensitivity was simulated by EDTA application for five minutes. The specimens were randomly allocated into five groups (n=11), according to treatment: No treatment - Control (C), Duraphat (DUR), Desensibilize Nano P (NP), ClinPro XT Varnish (XTV), and ClinPro White Varnish (CWV). They were then submitted to erosive/abrasive cycling for five days. After EDTA, treatment, and cycling, the specimens were analyzed with an environmental scanning electron microscope (ESEM) to verify the number of opened dentin tubules (ODT) which were counted by using ImageJ software, and with a profilometer to determine the surface curvature/loss. ESEM data were analyzed with two-way repeated measure analysis of variance and Tukey tests. For the profilometer, data were analyzed with Kruskal-Wallis, Tukey, and Mann-Whitney tests.

Results:

After treatment, all groups showed lower ODT than the control, without significant differences between them. After cycling, the only group that showed lower ODT than the control was group XTV; however, it did not significantly differ from the other groups. For the profilometric analysis, there were significant differences in SL between the experimental times after treatment and after cycling for all groups (p&lt;0.05). After cycling, no surface loss was detected in groups DUR and XTV, which presented a significantly different curvature than group NP and the control group, but not from group CWV. Surface loss was detected for the control and groups NP and CWV, without difference among them.

Conclusion:

All desensitizing agents tested presented promising results concerning the obliteration of dentin tubules immediately after treatment. XTV was the only desensitizer capable of preventing the reopening of the tubules after the erosive/abrasive challenges. XTV and DUR presented a protective effect against dentin erosive wear.

Comparison of remineralization by fluoride varnishes with and without casein phosphopeptide amorphous calcium phosphate in primary teeth

OBJECTIVE

To compare MI (5% NaF with 2% CPP-ACP) and Prevident (5% NaF) varnishes in remineralizing caries-like lesions in primary teeth regarding calcium and phosphate enamel content and lesion depth.

MATERIAL AND METHODS

Caries-like lesions were created in 48 primary teeth which were divided into 2 halves; one left untreated (control) and the other half treated with MI or Prevident varnishes. Calcium and phosphate content was assessed using energy dispersive X-ray spectrometer and reduction in lesion depth was assessed using polarized light microscopy. Demineralization and remineralization values in each group were compared using paired t test and percentage change between groups was compared using t test and Mann Whitney U test.

RESULTS

A greater percentage increase of calcium was observed in MI than Prevident specimens (median = 8.97 and 2.67, p < .0001), with greater calcium phosphate ratio percentage increase (median = 28.96 and 7.40) and phosphate percentage reduction (median = 15.5 and 4.51). The mean (SD) percentages reduction in lesion depth in the MI varnish was significantly greater than in Prevident varnish (44.41 (7.12) and 22.73 (9.35), p < .0001).

CONCLUSIONS

MI varnish had better remineralization effect in primary teeth than Prevident varnish in terms of higher mineral content and shallower lesion depth.

Comparison of the Efficacy of Different Fluoride Varnishes on Dentin Remineralization During a Critical pH Exposure Using Quantitative X-Ray Microtomography

OBJECTIVES:

The objective of this in vitro study was to quantify the amount of mineral change in demineralized dentin at pH 5.5 after the application of dental varnishes containing fluoride with casein phosphopeptide-amorphous calcium phosphate, fluoride and bioglass, or fluoride alone.

METHODS AND MATERIALS:

A total of 12 extracted human sound mandibular premolar root samples were coated with an acid-resistant varnish, leaving a 2 × 3 mm window at the outer root surface. These root specimens were then randomly divided into four groups and separately subjected to the demineralizing cycle at a pH of 4.8 for five days to create artificial caries-like lesions in dentin. Subsequently, each sample was imaged using quantitative x-ray microtomography (XMT) at a 15-μm voxel size. Each test group then received one of the following treatments: dental varnish containing casein phosphopeptide-amorphous calcium phosphate and fluoride (CPP-ACP, MI varnish, GC Europe), bioglass and fluoride (BGA, Experimental, Dentsply Sirona), or fluoride alone (NUPRO, Dentsply Sirona), as well as a control group, which received no treatment. These samples were kept in deionized water for 12 hours. The thin layer of varnish was then removed. All samples including the nonvarnish group were subjected to the second demineralizing cycle at pH 5.5 for five days. The final XMT imaging was then carried out following the second demineralizing cycle. XMT scan was also carried out to varnish samples at 25 μm voxel size. The change in mineral concentration in the demineralized teeth was assessed using both qualitative and quantitative image analysis.

RESULTS:

There was an increase in radiopacity in the subtracted images of all varnish groups; a significant increase in mineral content, 12% for the CPP-ACP and fluoride ( p≤0.05 and p≤0.001), 25% BGA ( p≤0.001), and 104% fluoride alone varnish ( p≤0.001). There was an increase in the size of radiolucency in the lesion area with a significant decrease in mineral content in the nonvarnish group, 10% ( p≤0.05 and p≤0.001).

CONCLUSIONS:

There was encouraging evidence of a remineralization effect following the application of dental varnish on dentin and also an observed resistance to demineralization during the acidic challenge in all cases. However, a dental varnish containing fluoride alone appeared to have a much greater effect on dentin remineralization when compared with CPP-ACP with fluoride and bioglass with fluoride.

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.

In vitro Comparison of Antimicrobial Activity of Conventional Fluoride Varnishes Containing Xylitol and Casein Phosphopeptide-Amorphous Calcium Phosphate

Objective

Different fluoride varnishes are used for the prevention of dental caries. The aim of this study was to compare the antimicrobial effect of different fluoride varnishes, containing xylitol and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), on Streptococcus mutans.

Materials and Methods

In this in vitro study, the antibacterial effects of four varnishes, namely Polimo and V-varnish (containing xylitol), MI varnish (containing CPP-ACP), and Preventa, were evaluated against S. mutans. The disc diffusion method was used for testing the bacterial sensitivity. The data were analyzed using the Kruskal-Wallis and Mann-Whitney U-tests.

Results

According to the results, Polimo showed the highest antibacterial effects, compared to the other three varnishes (P ≤ 0.05). Growth inhibition zones were not observed in V-varnish and Preventa. The mean diameter of inhibition zone around the MI varnish was significantly higher, compared to those of the V varnish and Preventa (P ≤ 0.05).

Conclusion

As the findings indicated, the fluoride varnish containing xylitol and CPP-ACP could be more effective iAQ1n the prevention of dental caries.

Effect of Silver Nitrate and Sodium Fluoride with Tri-Calcium Phosphate on Streptococcus mutans and Demineralised Dentine

This study investigated the effect of 25% silver nitrate (AgNO₃) and 5% sodium fluoride (NaF) varnish with functionalized tri-calcium phosphate (fTCP) on a Streptococcus mutans (S. mutans) biofilm and dentine caries lesion. Demineralised dentine specimens were treated with 25% AgNO₃ and 5% NaF + fTCP (Group 1), 25% AgNO₃ and 5% NaF (Group 2), 25% AgNO₃ (Group 3), or water (Group 4). The specimens were subjected to a S. mutans biofilm challenge after treatment. The biofilm was then studied via scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and colony forming units (CFU). The specimens were assessed by micro-computed tomography, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). SEM and CLSM revealed less biofilm in Groups 1 to 3. The log₁₀ CFU of Groups 1 to 4 were 4.5 ± 0.7, 4.4 ± 0.9, 4.4 ± 0.9, and 6.7 ± 1.0, respectively (Groups 1, 2, 3 < 4, p < 0.001). The lesion depths of Groups 1 to 4 were 212.6 ± 20.1 µm, 280.8 ± 51.6 µm, 402.5 ± 61.7 µm, and 497.4 ± 67.2 µm, respectively (Groups 1 < 2 < 3 < 4, p < 0.001). XRD demonstrated silver chloride formation in Groups 1, 2, and 3. FTIR found the amide I: HPO₄²⁻ values of the four groups were 0.22 ± 0.05, 0.25 ± 0.05, 0.41 ± 0.12, and 0.64 ± 0.14, respectively (Groups 1, 2 < 3 < 4; p < 0.001). In conclusion, this study revealed that AgNO₃ and NaF + fTCP reduced the damage of dentine caries by cariogenic biofilm.

Caries-Preventive Effect of NaF, NaF plus TCP, NaF plus CPP-ACP, and SDF Varnishes on Sound Dentin and Artificial Dentin Caries in vitro

The aim of this study was to compare the caries-preventive effect of different fluoride varnishes on sound dentin as well as on artificial dentin caries-like lesions. Bovine dentin specimens (n = 220) with one sound surface (ST) and one artificial caries lesion (DT) were prepared and randomly allocated to 11 groups. The interventions before pH cycling were as follows: application of a varnish containing NaF (22,600 ppm F-; Duraphat [NaF0/NaF1]), NaF plus tricalcium phosphate (22,600 ppm F-; Clinpro White Varnish Mint [TCP0/TCP1]), NaF plus casein phosphopeptide-stabilized amorphous calcium phosphate complexes (CPP-ACP; 22,600 ppm F-; MI Varnish [CPP0/CPP1]), or silver diamine fluoride (SDF; 35,400 ppm F-; Cariestop 30% [SDF0/SDF1]) and no intervention (NNB/N0/N1). During pH cycling (14 days, 6 × 120 min demineralization/day) half of the specimens in each group were brushed (10 s; 2 times/day) with either fluoride-free (“0”; e.g., TCP0) or 1,100 ppm F- (“1”; e.g., TCP1) dentifrice slurry. In another subgroup, the specimens were pH cycled but not brushed (NNB). Differences in integrated mineral loss (ΔΔZ), lesion depth (ΔLD), and colorimetric values (ΔΔE) were calculated between the values after initial demineralization and those after pH cycling, using transversal microradiography and photographic images. After pH cycling, no discoloration could be observed. Furthermore, NNB, N0, and N1 showed significantly increased ΔZDT/LDDT and ΔZST/LDST values, indicating further demineralization. In contrast, CPP0, CPP1, SDF0, and SDF1 showed significantly decreased ΔZDT/LDDT values, indicating remineralization (p ≤ 0.004; paired t test). CPP0, CPP1, SDF0, and SDF1 showed significantly higher changes in ΔΔZDT/ΔLDDT and ΔΔZST/ΔLDST than NNB, N0, and N1 (p < 0.001; Bonferroni post hoc test). In conclusion, under the conditions chosen, all fluoride varnishes prevented further demineralization. However, only NaF plus CPP-ACP and SDF could remineralize artificial dentin caries-like lesions under net-demineralizing conditions, thereby indicating that NaF plus CPP-ACP and SDF may be helpful to high-caries-risk patients.

Influence of highly concentrated fluoride dentifrices on remineralization characteristics of enamel in vitro

OBJECTIVES

The aim of this in vitro study was to evaluate the role of highly fluoridated dentifrice on remineralization characteristics of lowly and highly pre-demineralized enamel artificial caries lesions.

METHODS

Bovine enamel specimens were prepared (pH 4.95; 21 days) and discriminated in either lowly [L] or highly [H] pre-demineralized artificial caries lesions. Specimens with a mean ΔZ_baseline,L (95% CI) of 5120 (4995; 5245) vol.% × μm and a mean ΔZ_baseline,H of 8187 (8036; 8339) vol.% × μm were selected and randomly allocated to 12 groups (n = 20). Treatments during pH-cycling (28 days; 6 × 60 min demineralization/day) were brushing 2×/day with fluoride-free (0 ppm F^- [L₀/H₀]), 1100 ppm F^- [L₁₁₀₀/H₁₁₀₀], 2800 ppm F^- [L₂₈₀₀/H₂₈₀₀], 5000 ppm F^- [L₅₀₀₀/H₅₀₀₀], 5000 ppm F^- + glycerin [L_{5000 + glycerin}/H_{5000 + glycerin}], and 5000 ppm F^- + TCP [L_{5000 + TCP}/H_{5000 + TCP}] containing dentifrices. Dentifrice slurries were prepared with deionized water (1:3wt/wt). After cycling specimens presenting lesion surface loss were discarded and for the remaining 202 specimens, transversal microradiographic (TMR) analyses (ΔZ_pH-cycle/LD_pH-cycle) were performed again. Changes in mineral loss (ΔΔZ = ΔZ_baseline - ΔZ_pH-cycle) and lesion depth (ΔLD = LD_baseline - LD_pH-cycle) were calculated.

RESULTS

Significant differences for ΔΔZ could be found between L₀, L₁₁₀₀, and L₅₀₀₀ as well as H₀, H₁₁₀₀, and H₂₈₀₀/H₅₀₀₀ (p ≤ 0.01; ANCOVA). Except for 0 ppm F^-, higher ΔΔZ could be found in highly compared with lowly demineralized specimens (p ≤ 0.004; ANCOVA). After pH-cycling, a second lesion front could only be observed in H₅₀₀₀ and H_{5000 + TCP}. The correlation between ΔΔZ and F^- was moderate for lowly and highly demineralized lesions (r_L = 0.591; p_L < 0.001; r_H = 0.746; p_H < 0.001), indicating a fluoride dose response for both.

CONCLUSION

For both baseline substrate conditions, a dose response for fluoride could be revealed.

CLINICAL SIGNIFICANCE

Remineralization characteristics of enamel directly depended on baseline mineral loss.