Remineralization effect of NaF, NaF with TCP, NaF with CPP-ACP and NaF with CXP varnishes on newly erupted first permanent molars: A randomized controlled trial

INTRODUCTION

The aim of this study was to evaluate the remineralization effect of NaF, NaF with TCP, NaF with CPP-ACP and NaF with CXP varnishes on newly erupted first permanent molars using laser fluorescence (LF) method. The study was a randomized, double-blind, controlled trial with four parallel groups.

METHODS

The study was carried out in 48 high caries-risk children (DMFS >8), aged 6-7 years with newly erupted permanent first molars (initial lesion with 13 < LF value<30). A total of 140 teeth were divided randomly into four groups (n = 35): G1.Duraphat Varnish containing 5% NaF, G2. Clinpro™ White Varnish containing 5% NaF with TCP, G3.Embrace™ Varnish containing 5% NaF with CXP, G4. MI Varnish containing 5% NaF with CPP-ACP. All dental treatments of the patients were completed before the varnish application. The varnishes were applied to the targeted teeth at baseline, 1 and 3 months. Patients were called for follow-up appointments at 1, 3 and 6 months, and LF scanning was used to monitor mineralization changes. Data were analysed statistically by Wilcoxon signed-rank and Mann-Whitney U-tests.

RESULTS

In total, 40 children (122 teeth) completed the trial. At the end of 6 months, the amount of reduction in LF values (indicating remineralization) are as follows: NaF with CXP(6.87 ± 4.32) < NaF with TCP(7.36 ± 7.05) < NaF(7.40 ± 7.03) < NaF with CPP-ACP(8.33 ± 4.90). All of the varnishes resulted in significant decrease in LF measurements and there was no significant difference between control (NaF alone) group and other groups. Only MI varnish had a significantly greater remineralization effect than Embrace™ Varnish (p < 0.05).

CONCLUSION

As a non-invasive approach, CPP-ACP, TCP and CXP containing NaF varnishes have the potential to remineralize initial caries lesions on permanent first molars in high caries-risk children.

Surface roughness and microhardness of enamel white spot lesions treated with different treatment methods

Objective

To analyse the surface roughness and microhardness of artificial enamel white spot lesions before and after WSL formation, after treatment (Opalsutre™ microabrasion, Sylc® bioactive glass, and ICON® resin infiltration), and after pH cycling with the help of the profilometer surface roughness tester and the digital Vickers microhardness tester.

Materials and methods

Seventy-five extracted molars were used to acquire one hundred specimens. 50 specimens were randomly assigned to five groups (n = 10) for the surface roughness study: 1) Sound group, 2) WSL group, 3) micro abrasion (MA; Opalustre, Ultradent, South Jordan, UT, USA), 4) bioactive glass 45S5 Sylc powder (Sylc; Denfotex Research Ltd, Inverkeithing, UK), and 5) ICON resin infiltration (ICON; DMG, Hamburg, Germany). An additional 25 specimens were used to obtain 50 enamel slabs for the surface microhardness study, which were also assigned to the same groups. All groups underwent a final stage of pH cycling. Surface roughness and surface microhardness measurements were performed at different stages for all groups.

Results

Regarding surface roughness, ICON significantly reduced the surface roughness compared to Opalustre and Sylc, with no significant difference between Opalustre and Sylc. In terms of surface microhardness, ICON showed the highest improvement, followed by Sylc and then Opalustre. Both surface roughness and microhardness were significantly affected by demineralization, partially improved after treatment, and then regressed significantly after pH cycling.

Conclusion

ICON resin infiltrant can be considered as a superior treatment option for improving surface roughness and microhardness, while Opalustre demonstrated relatively the poorest performance compared to the other treatment options. It is noteworthy that the pH cycling procedure had an adverse impact irrespective of the treatment option used.

Comparison of therapies of white spot lesions: a systematic review and network meta-analysis

OBJECTIVE

White spot lesions (WSLs), the earliest evidence of enamel demineralization, are considered amenable to intervention to achieve a remineralized or arrested state of caries. The management of WSLs is quite challenging, and there is no definitive cure as yet. We performed a network meta-analysis to assess the efficacy of seven therapies for WSLs and gave a hierarchy of them.

MATERIALS AND METHODS

We systematically searched the PubMed, EMBASE, Cochrane, and Web of Science databases (last search: July 2022) to identify all relevant studies. We limited our search to studies published in English. Randomized controlled designed in vitro/clinical trials related to the efficacy of the seven therapies for WSLs were included. Data extraction was performed independently by two reviewers. The risk of bias (ROB) 2.0 tool from Cochrane and a previous in vitro methodological tool will be used for the quality assessment. Variations in quantitative light-induced fluorescence (QLF), laser fluorescence (LF), and lesions area were the primary outcome measures. Standard mean difference (SMD) was used as the effect size for the Network meta-analysis (NMA). Consistency and inconsistency tests were conducted. The hierarchy of 7 treatment effects was evaluated using surface probabilities under cumulative ranking (SUCRA). Publication bias was evaluated using a bias plot.

RESULTS

Forty-two articles were included in the systematic review. Thirty-one of them, with a total of 1906 participants, were included in the network meta-analysis. The studies owned a low and moderate risk of bias. This analysis does not suffer from significant inconsistency. The difference between 4 groups 'self-assembled peptide (SAP) P11-4', 'P11-4 + Fluoride Varnish (FV)', 'Resin Infiltration (RI)', 'casein phosphor peptides-amorphous calcium fluoride phosphate (CPP-ACFP)' and the 'Control' group was found to be statistically significant. Compared to the 'FV' and 'casein phosphor peptides-amorphous calcium phosphate (CPP-ACP)' groups, the 'P11-4 + FV" group and 'RI" group made a significant difference. The hierarchy was evident in the SUCRA values of 7 therapies. P11-4 + FV and RI were considered effective therapies compared to the control group or the FV group (gold standard group).

CONCLUSIONS

The available evidence suggests that resin infiltration and P11-4 in combination with fluoride varnish had advantages over gold standard (FV). The effect of tricalcium phosphate-based drugs and fluoride is not very noticeable. Overall, drugs based on P11-4 and resin infiltration will be better therapies. Using more than two drugs in combination also would increase efficacy.

Biomimetic Dentin Repair: Amelogenin-Derived Peptide Guides Occlusion and Peritubular Mineralization of Human Teeth

Exposure of dentin tubules due to loss of protective enamel (crown) and cementum (root) tissues as a result of erosion, mechanical wear, gingival recession, etc. has been the leading causes of dentin hypersensitivity. Despite being a widespread ailment, no permanent solution exists to address this oral condition. Current treatments are designed to alleviate the pain by either using desensitizers or blocking dentin tubules by deposition of minerals or solid precipitates, which often have short-lived effects. Reproducing an integrated mineral layer that occludes exposed dentin with concomitant peritubular mineralization is essential to reestablish the structural and mechanical integrity of the tooth with long-term durability. Here, we describe a biomimetic treatment that promotes dentin repair using a mineralization-directing peptide, sADP5, derived from amelogenin. The occlusion was achieved through a layer-by-layer peptide-guided remineralization process that forms an infiltrating mineral layer on dentin. The structure, composition, and nanomechanical properties of the remineralized dentin were analyzed by cross-sectional scanning electron microscopy imaging, energy dispersive X-ray spectroscopy, and nanomechanical testing. The elemental analysis provided calcium and phosphate compositions that are similar to those in hydroxyapatite. The measured average hardness and reduced elastic modulus values for the mineral layer were significantly higher than those of the demineralized and sound human dentin. The structural integration of the new mineral and underlying dentin was confirmed by thermal aging demonstrating no physical separation. These results suggest that a structurally robust and mechanically durable interface is formed between the interpenetrating mineral layer and underlying dentin that can withstand long-term mechanical and thermal stresses naturally experienced in the oral environment. The peptide-guided remineralization procedure described herein could provide a foundation for the development of highly effective oral care products leading to novel biomimetic treatments for a wide range of demineralization-related ailments and, in particular, offers a potent long-term solution for dentin hypersensitivity.

Effect of different surface treatments on the microhardness and colour change of artificial enamel lesions

BACKGROUND

To investigate the effect of three different surface treatments on the microhardness and colour change of artificial enamel lesions.

MATERIALS AND METHODS

One hundred bovine teeth were randomly assigned into four groups. Artificial enamel lesions were created using demineralizing solution for all groups except the sound enamel group. Different surface treatments were then performed G1: resin-infiltrant; G2: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP); G3: artificial saliva; G4: Sound Enamel. Each group was subdivided into three subgroups, where each subgroup was subjected to a different testing method. Subgroup 1: surface microhardness; subgroup 2: cross-sectional microhardness; subgroup 3: colour measurement. Statistical analysis was performed by ANOVA, followed by Tukey's post hoc test.

RESULTS

Sound enamel group recorded the highest surface and cross-sectional microhardness results. No significant difference was found between the resin-infiltrant group and CPP-ACP regarding surface and cross-sectional microhardness at different lesion depths. Resin-infiltrant group showed the least colour change (∆E) results compared to the other groups.

CONCLUSION

Resin-infiltrant can effectively enhance surface microhardness and enamel resistance to demineralization, additionally, reduces the staining susceptibility of white spot lesions (WSLs) after treatment. CPP-ACP application for 4 weeks seems to improve surface microhardness; however, has a limited effect in resisting staining of WSLs after treatment. © 2022 Australian Dental Association.

Effect of Preirradiation Fluoride Treatment on the Physical Properties of Dentin

Objective. To determine the effects of preirradiation fluoride treatments on the Knoop hardness of dentin. Materials and Methods. Human posterior teeth mounted into acrylic resin molds were polished with silicon carbide (SiC) abrasives and 3-micron diamond paste. The Knoop hardness of dentin was measured with a Leco hardness instrument. The teeth were divided into groups of ten teeth per group as follows: no treatment (control), treatment with silver diamine fluoride (SDF), MI varnish (MI), and cavity shield (CS). The teeth were exposed to 2 Gy of daily radiation for six weeks using an X-Rad 320ix biological irradiator. Hardness was measured weekly, before, during, and after irradiation. The teeth were stored in artificial saliva at 37oC between radiation treatments. Results. In preirradiation dentin, a Knoop hardness value of 58.8 (14.1) KHN was obtained. Treatment with SDF significantly increased KHN before irradiation. Immediately after radiation treatment, hardness was significantly reduced in all experimental groups. Postirradiation fluoride treatments increased the hardness of dentin to varying degrees. Conclusions. Preirradiation fluoride treatment does not provide protection from decreases in the hardness of dentin. Treatment of teeth with fluoride formulations after radiation progressively restores the hardness of dentin to different degrees.

A Comparison of NovaMin™ and Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride on Enamel Remineralization - An In vitro Study Using Scanning Electron Microscope and DIAGNOdent®

Aim:

The aim of this study was to compare the efficacy of NovaMin^™ (SHY-NM) and casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) (tooth mousse plus^™) on enamel remineralization using DIAGNOdent^® and scanning electron microscope (SEM).

Methodology:

Eighty-six natural permanent maxillary first premolars were selected and randomly divided into two groups of 43 each, Group A (NovaMin^™) and Group B (CPP-ACPF). All the samples were assessed using DIAGNOdent^® (KaVo) at the baseline, after demineralization, and remineralization after 7 days. Two samples were randomly selected from each group after remineralization to evaluate the surface changes using SEM at × 1000 and × 2000.

Results:

The mean value of remineralization was highest for Group A NovaMin^™ (6.56 ± 0.93) compared to Group B, CPP-ACPF (tooth mousse plus^™) (6.02 ± 1.09). The maximum demineralization to remineralization value within the groups showed that the mean values in Group B CPP-ACPF (7.02 ± 3.02) was higher than Group A NovaMin^™ (6.42 ± 2.21). The difference in remineralizing potential between the groups and demineralization to remineralization value in within-group comparison was not found to be statistically significant.

Conclusion:

On comparing Group A NovaMin^™ and Group B CPP-ACPF, Group B CPP-ACPF showed a higher amount of remineralization than Group A NovaMin^™. From the present study, it can be inferred that both the experimental groups have the potential for remineralization.

Comparative evaluation of remineralizing potential of commercially available agents MI paste, Remin pro, and Clinpro using Scanning Electron Microscope and Energy Dispersive X-ray: An in vitro study

Background:

According to recent approaches, the prevention of initial dental caries is achieved using certain noninvasive methods. One such method is the topical application of remineralizing agents. Various remineralizing products are commercially available, but their efficacy is uncertain.

Aim:

The aim of the study was to evaluate the remineralizing potential of MI, Reminpro, and Clinpro using scanning electron microscope (SEM) and energy dispersive X-ray (EDX).

Methodology:

Forty extracted human premolars were collected. The samples were decoronated and the crown portion was coated with nail varnish leaving behind a 3 mm × 3 mm window on the labial surface. The samples were soaked in demineralizing solution for 4 days to create an artificial lesion, followed by SEM-EDX analysis. The samples were then randomly divided into 4 groups Control, MI, Remin Pro, and Clinpro with ten samples each. The remineralizing agents were applied according to the group and subjected to pH cycling for 21 days which was followed by SEM-EDX analysis. Data obtained were statistically analyzed using SPSS IBM version 23 (ANOVA, post hoc-Tukey, and Paired-t-test).

Results:

Ca and P were increased after remineralization in all groups. Between groups, the increase was more for ReminPro, followed by Clinpro and MI.

Conclusion:

In this study, the remineralizing potential of Remin Pro was effectively more, followed by Clinpro and MI.

The Effect of the Er:YAG Laser and MI Paste Plus on the Treatment of White Spot Lesions

Introduction: White spot lesions (WSLs) occurring after orthodontic treatment lead to patient dissatisfaction and aesthetic problems. The role of calcium-phosphate demineralization systems and the Er:YAG laser in the treatment of these lesions has recently been taken into account. This study aimed to investigate the effect of the Er:YAG laser and MI Paste Plus on the treatment of WSLs. Methods: A total of 65 premolars extracted due to orthodontic treatment were studied in this research. To create enamel lesions, the teeth were placed in a demineralizing solution. The teeth were then randomly divided into five groups (n=13) as follows: first group, control; second group, saliva; third group, MI Paste Plus; fourth group, Er:YAG laser; and fifth group, MI Paste Plus together with the Er:YAG laser. The teeth were kept in artificial saliva between treatment processes. Artificial saliva was replaced daily with fresh artificial saliva. The teeth were sectioned longitudinally by a disc from the middle of the exposed enamel and each section was mounted in polyester resin. The surface of the samples was serially polished and the microhardness of the teeth was measured at depths of 0, 50, 100, and 150 µm. Results: The microhardness was significantly higher in the fifth group than other groups at depths of 50 and 150 µm (P <0.005). Using the laser or MI Paste Plus alone did not significantly increase the microhardness. Conclusions: The combined application of the Er:YAG laser and MI Paste Plus is effective in the treatment of WSLs.

Comparative Evaluation of Microhardness and Enamel Solubility of Treated Surface Enamel with Resin Infiltrant, Fluoride Varnish, and Casein Phosphopeptide-amorphous Calcium Phosphate: An In Vitro Study

Aim and objective

The aim and objective of this study was to do a comparative evaluation of microhardness and enamel solubility (ES) of the treated surface enamel with resin infiltrant, fluoride varnish, and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP).

Materials and methods

An in vitro study was conducted on freshly extracted 85 sound permanent teeth of which 5 teeth were subjected to check for microhardness by the Vickers microhardness tester and the remaining teeth were exposed to demineralizing solution to create initial enamel lesions. These 80 teeth were assigned to four groups: group I—negative control (n = 20), group II—resin infiltrant (n = 20), group III—fluoride varnish (n = 20), and group IV—CPP-ACP (n = 20), and microhardness was checked after application. These teeth were exposed to caries attack three times a day for three consecutive days. The ES of these four groups was checked by calcium ion loss in the artificial cariogenic solution and whole saliva by an atomic absorption spectrophotometer.

Results

It was found that none of the experimental groups reached the microhardness values of sound intact teeth. At 3rd day, the values of microhardness were: group II = group III > group IV > group I. Maximum ES was found for group I (control) followed with group IV.

Conclusion

All agents used in study remineralized initial carious lesion. Fluoride varnish has the highest microhardness and showed least ES compared to other remineralizing agents.

Clinical significance

Fluoride varnish can be regarded as the choice of material to be used for the treatment of incipient carious lesions because of the low application frequency (once every 3–6 months), requires minimal patient compliance as it is a noninvasive procedure and less time consuming.

How to cite this article

Dhillon SN, Deshpande AN, Macwan C, et al. Comparative Evaluation of Microhardness and Enamel Solubility of Treated Surface Enamel with Resin Infiltrant, Fluoride Varnish, and Casein Phosphopeptide-amorphous Calcium Phosphate: An In Vitro Study. Int J Clin Pediatr Dent 2020;13(S-1):S14–S25.

Combined Near-Infrarred Light Transillumination and Direct Digital Radiography Increases Diagnostic In Approximal Caries

The objective of this study was to evaluate the clinical ability of Near-Infrared Light-Transillumination (NILT) for approximal dentinal caries detection and to compare with direct digital-radiography (DDR), as well as to determine whether the combination of both techniques improves the diagnostic capacity of the lesions. From 88 patients (over 18 years), 138 posterior teeth (76 molars and 62 premolars), that had approximal caries reached into dentine determined by DDR, were included. Lesion extension and DDR images were scored as follows: D0 = sound surface, D1/D2 = caries restricted to the outer/inner-half of the enamel, and D3/4 = caries restricted to the outer/inner-half of the dentin. Opening of the approximal surface using 0.5 mm-in-diameter diamond-bar was used as gold-standard. The lesion extension was then determined by the following criteria: no dentinal caries (D0/1/2) or dentinal caries (D3/4). Seventy-one lesions were D3 and 67 lesions were D4. Sensitivities of overall/D3/D4 were 98.0/95.7/100.0 (NILT) and 100/100/100 (DDR), respectively. Correlations with gold-standard were 0.92 (NILT) and 0.42 (DDR), respectively. The correlation increased to 0.97 (p = 0.045) on combining NILT and DDR. There was no difference in sensitivity between the methods (p > 0.05); but was differences in the correlation (p < 0.01). It can be concluded that NILT showed sensitivity similar to that of DDR and higher correlation than DDR for approximal dentinal caries detection. Accordingly, it may be used to monitor the progression of caries without exposing the patient to ionizing radiation, this being of particular interest in growing patients and in pregnant women. In this respect, NILT can be an effective diagnostic tool adjunctive to bitewing radiographs in detecting approximal dentinal caries. The combination of NILT and DDR represents an increase in the diagnosis of approximal lesions The proposed diagnostic protocol comprises visual examination, followed by NILT and DDR only if the former technique detects approximal caries.

Antibacterial and Remineralization Efficacy of Casein Phosphopeptide, Glycomacropeptide Nanocomplex, and Probiotics in Experimental Toothpastes: An In Vitro Comparative Study

Objective  This article evaluates the antibacterial and remineralization potential of experimentally prepared toothpastes containing different mixtures of nano casein phosphopeptides (nCPP), nano amorphous calcium phosphate (nACP), probiotic ­ Lactobacillus rhamnosus B-445 ( L. rhamnosus ), and nano glycomacropeptide (nGMP).

Materials and Methods  Five experimental toothpaste samples were prepared and grouped, such that group (A0) was the experimental toothpaste base formula. Groups (A1), (A2), (A3), and (A4) were the experimental toothpastes containing: nCPP; nCPP and nACP; nCPP, nACP, and L. rhamnosus , and nCPP, nACP, and nGMP, ­respectively. Group (A5) was the commercial group (GC MI Paste Plus). The five groups were screened against Streptococcus mutans (ATCC 25175) growth, and investigated for their remineralizing potentials on demineralized bovine enamel using Vickers ­microhardness test (Vickers hardness number [VHN]). Scanning electron microscope (SEM) images were obtained for the demineralized and remineralized enamel of the two most effective toothpastes against in vitro bacterial induced enamel demineralization. Statistical analysis was performed using one-way analysis of variance (ANOVA) as well as repeated measures ANOVA followed by Tukey’s post hoc test.

Results  Both (A3) and (A4) were significantly higher in mean inhibition zone ­diameters than group (A1) and (A2). Group (A4) showed the highest statistical ­significance in the mean difference between VHN values of demineralization and 15 days remineralization period. SEM images showed the deposition of nano-sized particles fill the ­microrough surface pattern of the etched enamel.

Conclusion  All these findings suggest the use of probiotic, nCPP–nACP, and nGMP as a dental anticariogenic and remineralizing active agents.

The in vitro remineralizing effect of CPP-ACP and CPP-ACPF after 6 and 12 weeks on initial caries lesion

Objective:

The aim of this in vitro study was to determine the effects of remineralization promoting agents containing casein phosphopeptide-stabilized amorphous calcium phosphate (CPP-ACP), or CPP-ACP in combination with fluoride (CPP-ACPF) on artificial white spot lesions (WSLs) after 6 and 12 weeks.

Methodology:

White spot lesions were created on 123 sectioned premolars (246 specimens) with a demineralization solution during a 96 hours pH-cycling regime. Two experimental groups were created: a CPP-ACP group (Tooth Mousse™), and a CPP-ACPF group (Mi Paste Plus™). Additionally, two control groups were created, one using only a conventional toothpaste (1450 ppm fluoride) and another one without any working agents. All teeth were also daily brushed with the conventional toothpaste except the second control group. Tooth Mousse™ and Mi Paste Plus™ were applied for 180 seconds every day. The volume of demineralization was measured with transverse microradiography. Six lesion characteristics regarding the lesion depth and mineral content of WSLs were also determined.

Results:

The application of CPP-ACP and CPP-ACPF had a significant regenerative effect on the WSLs. Compared to Control group 1 and 2 the volume of demineralization after 6 weeks decreased significantly for CPP-ACP (respectively p<0.001 and p<0.001) and CPP-ACPF (respectively p=0.001 and p=0.003). The same trend was observed after 12 weeks. For the CPP-ACPF group, WSL dimensions decreased significantly between 6 and 12 weeks follow-up (p=0.012). The lesion depth reduced significantly after application of CPP-ACP and CPP-ACPF but increased significantly in the Control groups. Mineral content increased for CPP-ACP and CPP-ACPF after an application period of 12 weeks, but this was only significant for CPP-ACP.

Conclusions:

Long-term use of CPP-ACP and CPP-ACPF in combination with a conventional tooth paste shows beneficial effects in the recovery of in vitro subsurface caries lesions.

Efficacy of different remineralization agents on treating incipient enamel lesions of primary and permanent teeth

Aims and Objectives:

The aim of this study was to compare the in vitro efficacy of different remineralization (RM) agents on RM of artificial caries by evaluating the density, light reflection, and the crystal size of the newly formed mineral in primary and permanent teeth.

Materials and Methods:

Caries-free primary and permanent molars were divided into seven groups (n = 20) and treated with: G1 – Deionized water, G2 – Colgate Cavity Protection, G3 – Sensodyne Rapid Relief, G4 – GC MI Paste Plus, G5 – Clinpro Tooth Creme, G6 – Clinpro 5000, and G7 – Sensodyne Repair and Protect. Lesion depths were evaluated using laser fluorescence (DIAGNOdent), and polarized light microscopy (PLM), and the minerals were evaluated using X-ray diffractometry (XRD).

Results:

The highest decrease in laser fluorescence readings was observed in G6 for both primary and permanent teeth. No significant difference was observed between G2, G4, G5, and G6 in permanent teeth and G4 and G6 in primary teeth (P > 0.05). In PLM analyses, lesions depths were found to be lower in G6 compared to the other groups. No significant difference was observed between G2, G4, and G6 (P < 0.05). XRD evaluation showed that the newly formed mineral in G6 was denser and highly crystallized compared to the other groups.

Conclusion:

This in vitro study demonstrated that Clinpro 5000 is more efficient in remineralizing incipient enamel lesions compared to the other agents tested.

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.

The effect of diode laser irradiation associated with photoabsorbing agents containing remineralizing materials on microhardness, morphology and chemical structure of early enamel caries

Background

This study investigated the effects of laser irradiation associated with photo-absorbing agents containing sodium fluoride (NaF), MI paste Plus or Remin Pro® on microhardness and surface structure of white spot lesions (WSLs).

Material and Methods

Fifty-six premolars were divided into two halves, then immersed in a demineraling solution to induce WSLs. The samples were divided into 8 groups by treatment (n=12) : (1) control, (2) diode laser (810 nm, 500 mW, 90 s), (3) NaF, (4) MI Paste plus, (5) Remin Pro®, (6) NaF + Laser, (7) MI Paste Plus + Laser, (8) Remin Pro® + Laser. Microhardness was measured before and after remineralization treatments. Two samples from each group were selected for SEM analysis.

Results

Microhardness increased significantly after all treatments with the exception of control, Laser and Remin Pro® groups (p >0.05). ANOVA revealed no significant difference in initial microhardness (P=0.21), whereas a significant difference was noted after treatment (P=0.009). The application of sodium fluoride with or without laser irradiation produced the highest microhardness among the groups (p<0.05). SEM analysis revealed some cracks on lased enamel and non-homogenous coatings of minerals after the use of remineralizing products.

Conclusions

The use of NaF either alone or combined with laser irradiation was the most effecttive strategy for increasing microhardness of WSLs. The application of diode laser through photoabsorbing agents containing sodium fluoride or MI Paste Plus did not produce any additional effects in enhancing remineralization of WSLs, whereas the combined application of diode laser with Remin Pro® was effective.

Key words:CPP-ACP, Enamel caries, fluoride, Hydroxyapatite, Low level laser, Microhardness, Remineralization, casein phosphopeptide amorphous calcium phosphate.

In vitro and in vivo evaluation of electrophoresis-aided casein phosphopeptide-amorphous calcium phosphate remineralisation system on pH-cycling and acid-etching demineralised enamel

Casein phosphate-amorphous calcium phosphate (CPP-ACP), as a remineralisation agent, is extensively used in managing demineralised enamel; however, its remineralisation kinetics is low. This study aimed to improve remineralisation kinetics of CPP-ACP by introducing a rapid remineralisation method with electrophoresis. In vitro, a pH-cycling enamel model was used to test remineralisation potentials of electrophoresis-aided CPP-ACP. For verifying remineralisation potentials of electrophoresis-aided CPP-ACP in vivo in a rabbit model, acid-etched enamel surface on rabbit maxillary incisors was remineralised by electrophoresis-aided CPP-ACP with 1.0 mA (group A) or 0.5 mA (group B). Both in vitro and in vivo, it was observed that electrophoresis was benefit to improve remineralisation kinetics of CPP-ACP, and the demineralised enamel was completely remineralised after 5 h. The Ca/P ratio in remineralised enamel consisted with that of hydroxyapatite, the microstructure in native enamel. Meanwhile, in vivo the micro-hardness of acid-etched enamel in group A (322.55 ± 31.90) and group B (322.55 ± 31.90) recovered up to the value of native enamel after 5 h remineralisation (p > 0.05). The Hematoxylin-eosin stain demonstrated that the electric field used in this study was safe on rabbit dental pulp. Therefore, this efficient and safe method has the potential to be applied in treating enamel deminerlisation.

Effect of dentifrice containing fTCP, CPP-ACP and fluoride in the prevention of enamel demineralization

OBJECTIVE

To evaluate the effect of different fluoride- and calcium- and/or phosphate-containing products on their ability to prevent enamel demineralization under pH cycling conditions.

MATERIAL AND METHODS

Enamel bovine specimens were assigned to the following groups: G1-MPP (MI Paste Plus, 0.2% NaF, Recaldent™, GC Corporation Tokyo, Japan); G2-FD (Crest™ Cavity Protection, 0.243% NaF, Procter & Gamble, USA); G3-CLP (Clinpro™ 5000, 1.1% NaF, 3M ESPE, USA); and G4-CO (Control without fluoride, Silica-based dentifrice; Daudt Ltda, Brazil). The specimens were soaked in demineralizing solution for 6 h and remineralizing solution for 18 h alternatively for 10 days. The toothpaste was prepared with deionized water in a 1:3 ratio (w/v) for three minutes daily. The solutions were renewed every 48 h. After cycling, enamel changes were analysed by percentage change of SMH (%SMH) and energy-dispersive X-ray spectroscopy (EDS). The %SMH value observed for G3-CLP (2.9 ± 39.2) was higher than that found in G4-CO (-13.0 ± 20.7), G1-MPP (-8.9 ± 20.9) and G2-FD (-3.9 ± 27.1). The %SMH was similar for all treatment groups (one-way ANOVA and Tukey's HSD; p < .05). The pH, Ca²⁺ and P_total in the remineralization solutions were not different among all groups (Kruskal-Wallis; p < .05). At 24 h, the Ca²⁺ concentration in the demineralization solution was significantly lower in G1-MPP. Ca²⁺ concentration increased in all groups after 48 h, except for G3-CLP. The EDX quantitative analysis showed that the atomic % of elements is lower level at G4-CO.

CONCLUSIONS

The Clinpro™ 5000 demonstrated having the most protective effect against demineralization; however, the % SMH was similar for all groups.

Effect of fluoride dentifrice and casein phosphopeptide-amorphous calcium phosphate cream with and without fluoride in preventing enamel demineralization in a pH cyclic study

OBJECTIVE

Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) complexes are anticariogenic and capable of remineralizing the early stages of enamel lesions. The use of fluoride prevents dental decay and the association of CPP-ACP with fluoride can increase remineralization. To evaluate the effect of CPP-ACP and CPP-ACPF creams associated with a fluoride dentifrice to prevent enamel demineralization in a pH cyclic model.

MATERIAL AND METHODS

Previously selected by surface microhardness (SH) analysis, human enamel blocks (n = 56) were submitted to daily treatment with dentifrice in a pH-cycling model. The enamel blocks were divided into four groups; G1: Crest™ Cavity Protection - Procter & Gamble (1,100 ppmF of NaF); G2: Crest™ +MI Paste (MP) - Recaldent™ GC Corporation Tokyo, Japan); G3: Crest™ + MI Paste Plus (MPP) - Recaldent™ 900 ppm as NaF, GC Corporation Tokyo, Japan), and G4: control, saliva. Specimens were soaked alternatively in a demineralizing solution and in artificial saliva for 5 d. The fluoride dentifrice, with proportion of 1:3 (w/w), was applied three times for 60 s after the remineralization period. The undiluted MP and MPP creams were applied for 3 m/d. After cycling, SH was re-measured and cross section microhardness measurements were taken.

RESULTS

The SH values observed for the groups G3 (257±70), G1 (205±70), and G2 (208±84) differed from the G4 group (98±110) (one-way ANOVA and Tukey's post hoc test). There were no differences between the groups G1xG2, G2xG3, and G1xG3 for demineralization inhibition. The percentage of volume mineral showed that, when applied with fluoride dentifrice, MPP was the most effective in preventing enamel demineralization at 50 µ from the outer enamel surface (Kruskal-Wallis and Mann Whitney p<0.05).

CONCLUSION

Fluoride dentifrice associated with CPP-ACPF inhibited subsurface enamel demineralization.

Influence of biofilm formation on the mechanical properties of enamel after treatment with CPP-ACP crème

The study aimed to investigate the effects of bacterial biofilms on changes in the surface microhardness of enamel treated with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with and without fluoride. Human enamel blocks with incipient caries-like lesions were divided into four groups of 13: G1: Saliva (Control); G2: fluoride dentifrice (Crest™, 1100 ppm as NaF); G3: CPP-ACP (MI Paste; Recaldent™); and G4: CPP-ACPF (MI Paste Plus; Recaldent™ 900 ppm as NaF). The specimens were soaked in demineralizing solution for 6 h and remineralized in artificial saliva for 18 h alternately for 10 days. The dentifrice was prepared with deionized water in a 1 : 3 ratio (w/w) or applied undiluted in the case of the CPP-ACP group. The surface microhardness (SMH) was evaluated at baseline, after artificial caries, after pH cycling and treatment with dentifrices, and after incubation in media with Streptococcus mutans for biofilm formation. The biofilms were exposed once a day to 2% sucrose and the biofilm viability was measured by MTT reduction. The percentage of change in surface microhardness (%SMHC) was calculated for each block. The data were analyzed by nonparametric test comparisons (α = 0.05). The %SMHC values observed in G2 were different from those of G1, G3, and G4 (p < 0.05). After biofilm formation, %SMHC was positive in G2 and G4 when compared to G1 and G3, but resistance to demineralization after biofilm formation was similar in all groups. In conclusion, the presence of biofilms did not influence the treatment outcomes of anticaries products.

In vitro effect of amorphous calcium phosphate paste applied for extended periods of time on enamel remineralization

Dental applications based on the unique characteristics of amorphous calcium phosphate stabilized by casein phosphopeptides (CPP-ACP) have been proposed, as well as the improvement of its properties.

The Effect of MIpaste Plus and Reminpro on Incipient Caries Using DIAGNOdent and SEM: An Invitro Study

BACKGROUND

The remineralization of early caries lesion has an effective role on decreasing caries. For initial remineralization of caries lesion, using Compounds of Casein phosphopeptides (CPP) in different studies has been proposed. REMINPRO including Fluoride, Xylitol and Calcium phosphate has just been offered in the market. This study aims to investigate the efficacy of Reminpro and MI paste plus in terms of remineralization of early enamel lesions.

MATERIALS AND METHODS

In 15 samples of healthy enamels of the maxillary first premolar teeth and 15 samples of Primary Mandibular First Molar under the effect of demineralized gel, artificial caries has been created. The samples have been divided in 3 groups of 20. After performing the cycles of demineralization and remineralization during 5 weeks, the samples were investigated by DIAGNOdent and two samples from each group were compared with SEM. To investigate the remineralization of enamel, two-way ANOVA and to compare the groups in pair, the post hoc tests were used.

RESULTS

The mean of mineralization of teeth in the group using reminpro was 25.2 ± 6.16 and in the group using MI paste plus was 23 ± 5.60, which was significantly high.

CONCLUSIONS

MI paste plus in mineralization of initial enamel caries were more efficient that reminpro pate.

In vivo analyses of the effects of polyamidoamine dendrimer on dentin biomineralization and dentinal tubules occlusion

This study evaluated the biomineralization and dentinal tubules occlusion abilities of the carboxyl-terminated polyamidoamine dendrimer (PAMAM-COOH) on human demineralized dentin in vivo at different time points. Demineralization dentin model with and without treated with PAMAM-COOH were sutured to the interior side of the rat's cheeks, that was incubated in the rats' saliva for 2, 4 and 6 weeks respectively. Finally, the newly formed precipitates were characterized by SEM, EDS, XRD and microhardness test. The hydroxyapatite (HA) on the dentin treated with PAMAM-COOH were formed gradually with the time going by, and the regenerated HA has a similar crystal structure with natural dentin, whereas the crystallites did not exist on the control group. The microhardness of PAMAM-COOH-applied specimens had a significantly higher than those without application. These results suggest that the PAMAM-COOH promoted the biomineralization of demineralized dentin and displayed favourable effects on blocking the open dentinal tubules.

Decalcification prevention around orthodontic brackets bonded to bleached enamel using different topical agents

BACKGROUND

The present study was conducted to evaluate the effect of different topical agents utilized for prevention of enamel decalcification around orthodontic brackets bonded to bleached and non-bleached enamel.

METHODS

Human maxillary premolars (n = 120) were divided into two equal groups. Teeth in group I were left without bleaching while those in group II were bleached with Vivastyle gel. Metal brackets were bonded to all the teeth using light-cured adhesive. Each group was divided into six equal subgroups (A, B, C, D, E, and F). In subgroup A, no material was applied (control). In subgroups B, C, D, E, and F, the following materials were applied respectively: Profluorid varnish, Enamel Pro Varnish, Ortho-Choice Ortho-Coat, GC Tooth Mousse, and GC MI Paste Plus. All teeth were cycled in a demineralization solution/artificial saliva for 15 days. Laser fluorescence was used to measure the level of enamel mineralization. The data were statistically analyzed.

RESULTS

Regarding the non-bleaching subgroups, all studied material revealed significant demineralization reduction in comparison to the control subgroup (P < 0.05). Ortho-Choice Ortho-Coat revealed the highest significant effect while GC Tooth Mousse showed the least effect. In bleached subgroups, Profluorid varnish, Enamel Pro Varnish, and Ortho-Choice Ortho-Coat significantly reduced demineralization (P < 0.05) while either GC MI Paste Plus or GC Tooth Mousse had no significant effects (P > 0.05).

CONCLUSIONS

Ortho-Choice Ortho-Coat, and Profluorid and Enamel Pro varnishes could be utilized successfully to reduce enamel demineralization around brackets bonded to either bleached or non-bleached enamel. GC MI Paste Plus and GC Tooth Mousse were effective only in non-bleached enamel.

Comparison of the effect of resin infiltrant, fluoride varnish, and nano-hydroxy apatite paste on surface hardness and streptococcus mutans adhesion to artificial enamel lesions

Introduction

Dental caries is a major public health problem, and Streptococcus mutans is considered the main causal agent of dental caries. This study aimed to compare the effect of three re-mineralizing materials: resin infiltrant, fluoride varnish, and nano-hydroxy apatite paste on the surface hardness and adhesion of Streptococcus mutans as noninvasive treatments for initial enamel lesions.

Methods

This experimental study was conducted from December 2015 through March 2016 in Babol, Iran. Artificial enamel lesions were created on 60 enamel surfaces, which were divided into two groups: Group A and Group B (30 subjects per group). Group A was divided into three subgroups (10 samples in each subgroup), including fluoride varnish group, nano-hydroxy apatite paste group (Nano P paste), and resin infiltrant group (Icon-resin). In Group A, the surface hardness of each sample was measured in three stages: First, on an intact enamel (baseline); second, after creating artificial enamel lesions; third, after application of re-mineralizing materials. In Group B, the samples were divided into five subgroups, including intact enamel, demineralized enamel, demineralized enamel treated with fluoride varnish, Nano P paste, and Icon-resin. In Group B, standard Streptococcus mutans bacteria adhesion (PTCC 1683) was examined and reported in terms of colony forming units (CFU/ml). Then, data were analyzed using ANOVA, Kruskal-Wallis, Mann-Whitney, and post hoc tests.

Results

In Group A, after treatment with re-mineralizing materials, the Icon-resin group had the highest surface hardness among the studied groups, then the Nano P paste group and fluoride varnish group, respectively (p = 0.035). In Group B, in terms of bacterial adhesion, fluoride varnish group had zero bacterial adhesion level, and then the Nano P paste group, Icon-resin group, intact enamel group, and the de-mineralized enamel group showed bacterial adhesion increasing in order (p < 0.001).

Conclusion

According to the study among the examined materials, the resin infiltrant increased the tooth surface hardness as the intact enamel and fluoride varnish had the highest reduction level for bacterial adhesion. Nano P paste had an effect between the two materials, both in increasing surface hardness and reducing bacterial adhesion.

An in vitro Comparative Evaluation of Three Remineralizing Agents using Confocal Microscopy

INTRODUCTION

The caries process has been thought to be irreversible, resulting in the permanent loss of tooth substance and eventually the development of a cavity. Recent approaches focused on application of remineralizing agents to incipient carious lesions, aim at controlling demineralization and promoting remineralization. Remineralizing agents create a supersaturated environment around the lesion; thus, preventing mineral loss and forces calcium and phosphate ions in the vacant areas.

AIM

To compare and evaluate the remineralization potential of Fluoride Varnish, CPP-ACP Paste (Casein Phosphopeptide-Amorphous Calcium Phosphate) and fTCP Paste (functionalized Tricalcium Phosphate) using confocal microscope.

MATERIALS AND METHODS

Two windows of 3X3mm were created on the labial cervical and incisal thirds in 60 permanent maxillary central incisors. The teeth were demineralized to create artificial caries and divided into three groups of 20 each. Group I specimens were coated with Fluoride Varnish once whereas those in CPP-ACP paste group and fTCP group were brushed for 2 minutes, twice daily for 20 and 40 days. The specimens were stored in artificial saliva during the study period and were later sectioned and observed under confocal microscope. Data obtained was statistically analyzed using Fischer's exact test, ANOVA and post-hoc Bonferroni's test.

RESULTS

Fluoride Varnish, CPP-ACP Paste and fTCP Paste showed remineralization of artificial carious lesions at both the time intervals. Fluoride varnish showed the highest remineralization followed by CPP-ACP Paste and fTCP Paste. A statistically significant increase in remineralization potential of CPP-ACP Paste and fTCP Paste was observed at the end of 40 days as compared to 20 days.

CONCLUSION

Fluoride varnish showed the greatest remineralization potential of artificial carious lesions followed by CPP-ACP Paste and fTCP Paste respectively.

Remineralizing potential of CPP-ACP applied for 1 min in vitro

AIM

To evaluate (1) the remineralizing potential of Tooth Mousse(®) (TM) on artificial carious lesions, when applied for 1 min, and (2) the benefit of a fluoridated dentifrice prior to TM application.

METHODS

Demineralisation caries-like lesions 120-200 μm deep were produced by placing molars in demineralizing solution for 96 h, sections 100-150 μm thick were then randomly assigned to four groups. Specimens were treated thrice daily with a non-fluoridated (Group A), or fluoridated dentifrice (1000 ppm) (Group B), or TM (Group C), or a fluoridated dentifrice followed by TM (Group D) then subjected to a 10-day pH cycling model. Lesion evaluation involved polarizing light microscopy and microradiography.

RESULTS

Application of TM in isolation (Group C) for 1 min resulted in significant increase in lesion depth (LD), however, an increase in mineral content deposition (V max) was not significant. Post treatment LD increases were greatest in Group A, then Group C and Group B respectively. A decrease in LD (by 19.9 %) was noted only after fluoridated dentifrice and TM (Group D) were applied consecutively for 1 min each (p < 0.05). Mineral content deposition was also greatest in this group (Group D) and both V max and LD changes were statistically significant when compared to other groups.

CONCLUSIONS

TM alone failed to remineralize carious lesions when applied for 1 min. However, remineralization occurred after a prior application of a fluoridated dentifrice.

Remineralizing potential of CPP-ACP creams with and without fluoride in artificial enamel lesions

BACKGROUND

This study evaluated the effect of pastes containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with and without fluoride on enamel demineralization.

METHODS

Human enamel blocks were used and after incipient caries-like lesions were formed, they were assigned to four groups: G1 - saliva; G2 - MI Paste (Recaldent^TM ); G3 - MI Paste Plus (Recaldent^TM 900 ppm as NaF); and G4 - Crest^™ (1.100 ppm as NaF). The specimens were soaked in demineralizing solution for 6 hours and remineralized in artificial saliva for 18 hours alternatively for 10 days. The dentifrice was prepared with deionized water in a 1:3 proportion (w/w) or applied undiluted in the case of the CPP-ACP formula. Demineralized enamel changes were analysed by surface microhardness (SMH), 3D-profilometry and SEM. Data were analysed by non-parametric Kruskal-Wallis and Mann-Whitney test comparisons and one-way ANOVA and Tukey's HSD post hoc test (α = 0.05).

RESULTS

The SMH values observed in the G2 (47.8 ± 28.5) and G3 (53.6 ± 27.6) groups were different from that of G4 (90.2 ± 17.1), which were significantly higher than that found in G1 (39.4 ± 14.2). The %SMH was significantly lower in G4 when compared to G1 (p < 0.001) and G3 (p < 0.05).

CONCLUSIONS

MI Paste Plus demonstrated a greater protective effect against demineralization than MI Paste and showed smoother surfaces.

Effects of Treatment with Various Remineralizing Agents on the Microhardness of Demineralized Enamel Surface

Background and aims. Remineralization of incipient caries is one of the goals in dental health care. The present study aimed at comparing the effects of casein phosphopeptide-amorphous calcium phosphate complex (CPP-ACP), Remin Pro^®, and 5% sodium fluoride varnish on remineralization of enamel lesions.

Materials and methods. In this in vitro study, 60 enamel samples were randomly allocated to six groups of 10. After four days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 underwent one-time treatment with fluoride varnish, CPP-ACP, and Remin Pro^®, respectively. Microhardness of groups 4-6 was measured not only after one-month treatment with the above-mentioned materials (for eight hours a day), but also after re-exposing to the demineralizing solution. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Fisher’s least significant difference (LSD) test.

Results. None of the regimens could increase microhardness in groups 1-3. However, one-month treatment regimens in groups 4-6 caused a significant increase in microhardness. The greatest microhardness was detected in the group treated with CPP-ACP (P = 0.001). In addition, although microhardness reduced following re-demineralization in all three groups, the mean reduction was minimum in the CPP-ACP-treated group (P < 0.001).

Conclusion. While long-term repeated application of all compounds improved microhardness, the remineralization potential of CPP-ACP was significantly higher than that of Remin Pro^® and sodium fluoride varnish.

Developing pathways for oral care in elders: evidence-based interventions for dental caries prevention in dentate elders

BACKGROUND

Dental caries is becoming an ever-growing challenge as the number of elders maintaining their teeth increases. There is a need for low-cost, effective preventive interventions to retain natural teeth for elders.

OBJECTIVE

The purpose of this article is to evaluate evidence based interventions for dentate elders, specifically the adjunct therapies of fluoride, chlorhexidine, xylitol, casein phosphopeptide-amorphous calcium phosphate, ozone, and herbal liquorice.

RESULTS

Fluoride interventions have demonstrated prevention and remineralization of dental caries in elders. Systematic reviews of the literature are unable to establish definitive conclusions regarding the effectiveness of other adjunct therapies in dental caries prevention.

CONCLUSIONS

Further research with elders requires improved study design with well designed multi-center trials. Considerations for new strategies for research of the effectiveness of therapies to reduce dental caries include the development and evaluation of combinations of therapeutic interventions and dental caries management by risk assessment.

Microshear Bond Strength of Adhesives to Enamel Remineralized Using Casein Phosphopeptide Agents

Objective

This study was carried out to evaluate the difference between bonding to demineralized enamel and remineralized enamel using casein phosphopeptide–amorphous calcium phosphate with fluoride (CPP-ACFP) or without fluoride (CPP-ACP) compared to normal enamel. Another aim was to test if the newly introduced Single Bond Universal adhesive system would show better bonding to any enamel condition in comparison to the other tested adhesive systems.

Methods

The lingual enamel surfaces of 40 non carious human third molars were divided into four main groups according to the enamel condition (ground normal enamel [negative control]; demineralized enamel [positive control]; and remineralized enamel with CPP-ACP or with CPP-ACFP, respectively). Within each main group, the lingual enamel surface of each tooth was sectioned into three slabs, resulting in 30 slabs that were distributed into three subgroups according to the adhesive system utilized (Clearfil S3 Bond Plus, Single Bond Universal, or G-aenial Bond). Two resin composite microcylinder buildups were made on each enamel slab using Filtek Z350 XT. The μSBS was evaluated at a crosshead speed of 0.5 mm/min. Modes of failure were detected using an environmental scanning electron microscope at 300× magnification.

Results

The two-way analysis of variance with repeated measures revealed a significant effect for the enamel condition. However, there was no significant effect for the type of adhesive system. The interaction between the enamel condition and the type of adhesive system was also not significant. Modes of failure were mainly adhesive except for the demineralized enamel. It showed a mixed type of failure, in which cohesive failure in enamel was recorded.

Conclusions

All single-step self-etch adhesives revealed comparable μSBS values to ground enamel and enamel remineralized with CPP-ACP or CPP-ACFP. Bonding to demineralized enamel was ineffective. With any enamel condition, no tested single-step self-etch adhesive was superior in its bonding.

Interproximal enamel reduction: an in vivo study

The study aimed to investigate the morphology and composition of the interproximal reduced enamel after exposition to saliva and casein phosphopeptide amorphous calcium phosphate with sodium fluoride (CPP-ACPF). Fourteen patients undergoing an orthodontic treatment with 4 premolars extractions participated to the study. Interproximal enamel reduction (IER) was performed on mesial surfaces of 3 extractive premolars for each patient while 1 served as untreated control. Premolars were assigned to 4 groups: No-S group, sound enamel as control; S-Ex group, stripped and immediately extracted enamel; S-Sal group, stripped and exposed to saliva enamel; S-CPP group, stripped enamel treated with CPP-ACPF. Teeth were extracted at different times, depending on the group they were assigned to and sliced into mesial and distal halves. Mesial surfaces were subjected to environmental scanning electron microscopy with energy dispersive X-ray spectrometry (ESEM/EDX) and to scanning electron microscopy (SEM) analysis. ESEM/EDX investigations showed no statistically significant differences in the content of calcium and phosphate between the 4 groups. SEM observations showed no difference in the morphological appearance of stripped enamel after 30 days of exposure to saliva and CPP-ACPF. Saliva and CPP-ACPF effects on stripped enamel in vivo showed no difference after 30 days.

A comparative evaluation of CO2 and erbium-doped yttrium aluminium garnet laser therapy in the management of dentin hypersensitivity and assessment of mineral content

PURPOSE

Dentin hypersensitivity is a potential threat to oral health. Laser irradiation may provide reliable and reproducible treatment but remains controversial. The present study aimed to evaluate the effects of CO2 or erbium-doped yttrium aluminium garnet (Er:YAG) laser therapy, and to assess mineral content.

METHODS

Eighteen human single-rooted teeth affected with advanced periodontitis were obtained. Buccal and lingual surfaces were planed to form 36 specimens. Ethylenediaminetetraacetic acid gel (24%) was applied to remove the smear layer and simulate hypersensitive teeth. The experimental groups were: group 1, control (no irradiation); group 2, CO2 laser (repetitive pulsed mode, 2 W, 2.7 J/cm(2)); and group 3, Er:YAG laser (slight contact mode, 40 mJ/pulse and 10 Hz). To evaluate dentinal tubule occlusion, six specimens per group (2-mm thickness) were prepared and observed using scanning electron microscopy (SEM) for calculation of the occlusion percentage. To evaluate the mineral content, six specimens per group (0.6-mm thickness) were used, and then the levels of Ca, K, Mg, Na, and P were measured by inductively coupled plasma-atomic emission spectrometry. In addition, the surface temperature of the specimens during laser irradiation was analyzed by a thermograph.

RESULTS

The SEM photomicrographs indicated melted areas around exposed dentinal tubules and a significantly greater percentage of tubular occlusion in the CO2 and Er:YAG laser groups than the control, and in the Er:YAG group than the CO2 laser group. In addition, no significant differences were noted among the experimental groups for the mineral elements analyzed. The CO2 laser group showed an evident thermal effect compared to the Er:YAG group.

CONCLUSIONS

CO2 and Er:YAG laser are effective in treating dentin hypersensitivity and reducing its symptoms. However, the Er:YAG laser has a more significant effect; thus, it may constitute a useful conditioning item. Furthermore, neither CO2 nor Er:YAG lasers affected the compositional structure of the mineral content.

Remineralization effect of CPP-ACP and fluoride for white spot lesions in vitro

OBJECTIVES

This in vitro study compared the remineralization effect on white spot lesions of casein phosphopeptide-amorphous calcium phosphate crème, or CPP-ACP (MI Paste™), 1.1% NaF dentifrice containing 5000ppm of fluoride (ControlRX™), or CPP-ACP crème with 900ppm of fluoride (MI Paste Plus™) with that of a control.

METHODS

Artificial white spot lesions were created on smooth enamel surfaces of sound molars using a previously reported demineralization model. Specimens were randomly assigned to four treatments (n=35) with a pH-cycling model over 30 days: Control (no treatment); MI Paste (10% CPP-ACP crème); F5000 (1.1% NaF dentifrice); or MI Paste Plus (10% CPP-ACP plus 900ppm fluoride crème). Products were applied following manufacturers' directions. Changes in mean lesion depth expressed by percent fluorescence loss (ΔF%), and lesion area (mm(2)) from baseline to after treatment were measured with light-induced fluorescence (QLF). Mean values of each parameter were compared between groups (p<0.05).

RESULTS

The remineralization pattern for the F5000 group was unique with marked initial remineralization during the first 10 days and little subsequent change. Based on mean lesion area, the F5000 demonstrated greater remineralization than Control, MI Paste and MI Paste Plus groups. Based on mean fluorescence loss, the F5000 group showed improved remineralization relative to MI Paste Plus, but did not differ statistically from the Control at the end of 30 days.

CONCLUSIONS

The 1.1% NaF dentifrice demonstrated overall greater remineralization ability than 10% CPP-ACP crème. However, the 1.1% NaF dentifrice was only as effective as the Control to reduce fluorescence loss.

CLINICAL SIGNIFICANCE

This study showed that a 1.1% NaF dentifrice (5000ppm) demonstrated greater remineralization ability than the CPP-ACP topical tooth crème and that the addition of fluoride to its formulation seems to enhance remineralization. Saliva also has the ability to exert an important remineralization effect over time.

A SEM and non-contact surface white light profilometry in vivo study of the effect of a crème containing CPP-ACP and fluoride on young etched enamel

The aim of this in vivo study was to evaluate the short and a longer term effect on enamel of the application of a crème containing 10% CPP-ACP and 900 ppm fluoride, in orthodontically planned, high caries-risk patients. Epoxy resin replicas of upper lateral incisors were obtained from polyvinyl siloxane (PVS) impressions, before and after etching. The right incisors were left untreated in order to control saliva remineralizing potential. The upper left surfaces were coated with a pea-size amount of the crème. Replicas were obtained at 3 weeks and 6 months and analyzed by SEM and non-contact surface white light profilometry. In the treated sample the profilometric roughness parameters at 3 weeks were statistically significantly lower than the control group values (p < 0.05). At 3 weeks SEM images of the enamel surface showed fewer irregularities. After 6 months, differences between test and control groups were not present on SEM images and profilometric values. CPP-ACP and fluoride crème had positive in vivo effects on enamel surfaces. Significant differences in surface roughness existed after a 3-week period of crème use.

Impact of Experimental Nano-HAP Pastes on Bovine Enamel and Dentin Submitted to a pH Cycling Model

This in vitro study evaluated the preventive potential of experimental pastes containing 10% and 20% hydroxyapatite nanoparticles (Nano-HAP), with or without fluoride, on dental demineralization. Bovine enamel (n=15) and root dentin (n=15) specimens were divided into 9 groups according to their surface hardness: control (without treatment), 20 Nanop paste (20% HAP), 20 Nanop paste plus (20% HAP + 0.2% NaF), 10 Nanop paste (10% HAP), 10 Nanop paste plus (10% HAP + 0.2% NaF), placebo paste (without fluoride and HAP), fluoride paste (0.2% NaF), MI paste (CPP-ACP, casein phosphopeptide-amorphous calcium phosphate), and MI paste plus (CPP-ACP + 0.2% NaF). Both MI pastes were included as commercial control products containing calcium phosphate. The specimens were treated with the pastes twice a day (1 min), before and after demineralization. The specimens were subjected to a pH-cycling model (demineralization–6-8 h/ remineralization-16-18 h a day) for 7 days. The dental subsurface demineralization was analyzed using cross-sectional hardness (kgf/mm 2 , depth 10-220 µm). Data were tested using repeated-measures two-way ANOVA and Bonferroni's test (p<0.05). The only treatment able to reduce the loss of enamel and dentin subsurface hardness was fluoride paste (0.2% NaF), which differed significantly from the control at 30- and 50-µm depth (p<0.0001). The other treatments were not different from each other or compared with the control. The experimental Nanop pastes, regardless of the addition of fluoride, were unable to reduce dental demineralization in vitro.

Amelogenin-assisted ex vivo remineralization of human enamel: Effects of supersaturation degree and fluoride concentration

The formation of organized nanocrystals that resemble enamel is crucial for successful enamel remineralization. Calcium, phosphate and fluoride ions, and amelogenin are important ingredients for the formation of organized hydroxyapatite (HAP) crystals in vitro. However, the effects of these remineralization agents on the enamel crystal morphology have not been thoroughly studied. The objective of this study was to investigate the effects of fluoride ions, supersaturation degree and amelogenin on the crystal morphology and organization of ex vivo remineralized human enamel. Extracted third molars were sliced thin and acid-etched to provide the enamel surface for immersion in different remineralization solutions. The crystal morphology and mineral phase of the remineralized enamel surface were analyzed by field emission-scanning electron microscopy, attenuated total reflection-Fourier transformed infrared and X-ray diffraction. The concentration of fluoride and the supersaturation degree of hydroxyapatite had significant effects on the crystal morphology and crystal organization, which varied from plate-like loose crystals to rod-like densely packed nanocrystal arrays. Densely packed arrays of fluoridated hydroxyapatite nanorods were observed under the following conditions: σ(HAP)=10.2±2.0 with 1.5±0.5 mg l(-1) fluoride and 40±10 μg ml(-1) amelogenin, pH 6.8±0.4. A phase diagram summarizes the conditions that form dense or loose hydroxyapatite nanocrystal structures. This study provides the basis for the development of novel dental materials for caries management.