The effect of casein phosphopeptide-amorphous calcium phosphate on remineralization of artificial caries-like lesions: an in vitro study

Development of an Artificial White Spot Lesion Creation Protocol: A Preliminary Study

BACKGROUND AND OBJECTIVES

Protocols that determine the lesion depth of specific demineralization solutions are lacking. This in vitro study aimed to evaluate various lesion depths of artificial white spot lesions (WSLs) at different exposure times.  Materials and methods: Artificial WSLs were created by placing 30 extracted human premolar teeth into 0.05M acetate buffer solution with a controlled environment of pH 4.4 at 37ºC, which were then exposed in the solution for various durations of 4, 5, 6, 8, 10, and 12 days. The specimens were visually examined using the Ekstrand-Ricketts-Kidd (ERK) system to confirm the WSL, followed by buccolingual sectioning, and evaluated under a scanning electron microscope (SEM) to measure the lesion depth.

RESULTS

The SEM showed that the mean lesion depths of representative specimens were 101.33 µm (day 4), 124 µm (day 5), 159 µm (day 6), 187 µm (day 8), 202 µm (day 10), and 212 µm (day 12). The artificial WSL was visually demonstrated in grades 1 and 2 of the ERK system.

CONCLUSIONS

The depths of the lesions increased as the duration increased from day 4 to day 12, indicating that the lesion depths increased with the more prolonged exposure to the acetate buffer solution.

Comparative Analysis of the Effectiveness of Four Distinct Remineralizing Agents in Artificial White Spot Lesions Following Chitosan Nanoparticle Pretreatment: An In Vitro Study

Aim The aim of the study was to compare the effectiveness of chitosan nanoparticle pretreatment with four different remineralizing agents in artificial white spot lesions. Methods  A total of 100 human maxillary first premolars were selected and divided into five groups of 20 samples in each group. Artificial white spot lesions were created by immersing the samples in the demineralizing solution for 96 hours. Chitosan pretreatment was done for all samples followed by subjecting Group I samples to artificial saliva (control), Group II samples to 3M Clinpro, Group III samples to GC Tooth Mousse, Group IV samples to SHY-NM, and Group V samples with Aclaim using a cotton applicator tip. Each group was divided into two subgroups of 10 samples, which were subjected to hardness testing and mineral content analysis. Surface microhardness and the calcium phosphorous ratio were recorded using a Vickers microhardness tester and energy-dispersive X-ray (EDAX) analysis at three levels i.e., baseline, after demineralization, and after remineralization and tabulated. Statistical analysis was conducted by analyzing data using ANOVA and post hoc followed by Dunnett's t-test using IBM SPSS Statistics for Windows, Version 16 (Released 2007; IBM Corp., Armonk, New York, United States). Results Vickers surface hardness testing and EDAX analysis showed statistically significant values for all the groups. Among them, maximum remineralization potential was seen in samples treated with Chitosan and 3M Clinpro combination, and minimum remineralization potential was seen in Chitosan and artificial saliva combination. Conclusion The addition of chitosan nanoparticles with various remineralizing agents showed a significant synergistic effect on remineralization activity. Also, chitosan and Clinpro combination showed the maximum surface hardness and EDAX analysis values when compared to other groups.

A Comparison of the Enamel Remineralisation Potential of Self-Assembling Peptides

BACKGROUND

The aim of this research was to compare the efficacy of the remineralising potential of self-assembling peptides (SAPs): Curodont Repair (P11-4), P26, and leucine-rich amelogenin peptides (LRAP) with the standard 5% NaF varnish (Duraphat) on early enamel caries lesions (EECLs).

METHODS

A demineralising solution (DS) was used to create artificial EECLs in human dental enamel specimens, which were randomly allocated to treatment groups: P11-4; P26 solution; LRAP solution; 5% NaF varnish; and deionised water (DIW). Each specimen was subjected to 8 days of pH cycling. Specimens from each test group were subjected to microcomputed tomography (micro-CT) and nanomechanical testing to assess mineral density (MD), hardness (H), and elastic modulus (EM) properties of sound, demineralised, and treated enamel.

RESULTS

The mean MD percentage gain was highest in the P26 and P11-4 groups, followed by the LRAP, 5% NaF varnish, and DIW groups. There were statistically significant differences amongst groups. In the outer layer of EECLs, the EM and H were highest in P26 and P11-4 groups, followed by the LRAP and 5% NaF varnish. In the inner layer of EECLs, the EM and H were highest in P11-4 and P26 groups, indicative of enhanced penetration and remineralisation of the deeper parts of the artificial EECLs.

CONCLUSIONS

P26 and P11-4 SAPs are more effective than 5% NaF varnish in remineralising the depth of EECLs.

Remineralization potential of dentifrices with calcium sodium phosphosilicate and functionalized tri-calcium phosphate in the deeper incipient carious lesions: An in vitro study

OBJECTIVES

This study evaluated the remineralization potential of calcium sodium phosphosilicate and functionalized tri-calcium phosphate (f-TCP) dentifrices in deeper incipient carious lesions (ICLs).

MATERIALS AND METHODS

Artificial ICLs were created by placing premolars into demineralizing solutions. Teeth were randomly assigned into four groups: calcium sodium phosphosilicate (Group 1), f-TCP (Group 2), 1450 ppm fluoride (Group 3), and distilled water (Group 4), which were subjected to 10-day pH cycling. Mineral density (MD) was assessed using microcomputed tomography (Micro-CT), while hardness (H) and elastic modulus (EM) were assessed using nanomechanical testing.

RESULTS

MD % gain was higher in Groups 1-3 than in Group 4. In addition, Groups 1 and 2 exhibited significantly higher MD % gain than Group 3. Also, Groups 1-3 showed significantly higher EM and H values than Group 4 in the outer enamel area; yet, Groups 1 and 2 displayed significantly higher EM and H values than Groups 3 and 4 in the inner enamel.

CONCLUSIONS

The MD, EM, and H of ICLs significantly increased with the addition of calcium sodium phosphosilicate or f-TCP to fluoridated dentifrices compared to standard fluoride dentifrices. The added active ingredients remineralized the deeper parts of the ICLs, while remineralization at the lesion surface was similar between tested dentifrices.

Aesthetic impact of resin infiltration and its mechanical effect on ceramic bonding for white spot lesions

BACKGROUND

Treating white spot lesions (WSLs) with resin infiltration alone may not be sufficient, raising questions about its compatibility with other treatments amid controversial or incomplete data. Therefore, this study aimed to assess the aesthetic feasibility of resin infiltration combined with bleaching, as well as its potential mechanical effect on ceramic bonding to WSLs.

METHODS

One hundred and fifty flat enamel surfaces of bovine incisors were prepared. Ninety specimens were deminerailized and randomly assigned to three groups(n = 30): post-bleaching resin infiltration (Bl-R), pre-bleaching resin infiltration (R-Bl), and only resin infiltration (R). Color, surface roughness and microhardness were assessed in immediate, thermocycling and pigmentation tests. The remaining sixty samples were randomly assigned to three groups (n = 20): control (Ctrl), bonding (Bo), pre-bonding resin infiltration (R-Bo). Shear bonding strength, failure mode, micro-leakage depth and interface morphology were evaluated after ceramic bonding. The Tukey test and analysis of variance (ANOVA) were used for statistical analysis.

RESULTS

For the effect of resin infiltration and bleaching on WSLs, the R-Bl group showed the worst chromic masking ability, with the highest |ΔL|, |Δa|, |Δb|, and ΔE values after treatment. Compared with those in the Bl-R group, the R-Bl and R groups showed significant time-dependent staining, which is possibly attributed to their surface roughness. For the effect of resin infiltration on the adhesive properties of WSLs, resin infiltration reduced the staining penetration depth of WSLs from 2393.54 ± 1118.86 μm to 188.46 ± 89.96 μm (P < 0.05) while reducing WSLs porosity in SEM observation.

CONCLUSIONS

Post-bleaching resin infiltration proved to be advantageous in the aesthetic treatment of WSLs. Resin infiltration did not compromise bonding strength but it did reduce microleakage and enhance marginal sealing. Overall, resin infiltration can effectively enhance the chromatic results of treated WSLs and prevent long-term bonding failure between ceramics and enamel. Based on these findings, the use of post-bleaching resin infiltration is recommended, and resin infiltration before ceramic bonding is deemed viable in clinical practice.

Effect of self-assembling peptide and other remineralizing agents on preventing initial enamel lesions around orthodontic brackets: An in vitro comparative study

OBJECTIVE

To investigate and compare the effect of self-assembling peptide SAP (P_11-4), casein phosphopeptide-amorphous calcium phosphate fluoride paste (CPP-ACPF), and fluoride varnish (FV) on preventing enamel demineralization around orthodontic brackets.

MATERIAL AND METHODS

Orthodontic brackets were bonded to the buccal surfaces of 80 freshly extracted human maxillary premolars. Teeth were randomly assigned to four groups (n=20) according to the remineralizing agent used as follows: SAP (P_11-4) group (Curodont™ Protect/Credentis), CPP-ACPF group (MI Paste Plus®/Recaldent™), fluoride varnish group (Profluoride varnish®/VOCO), and control group. All products were applied according to the manufacturer's instructions. Specimens were cycled in daily refreshed demineralizing and remineralizing solutions for 8h and 16h, respectively, for 28 days. The calcium/phosphorus ratio (Ca/P) and surface microhardness (SMH) were evaluated at baseline and at two and four weeks. Two-way ANOVA (analysis of variance), one-way ANOVA and repeated measures ANOVA were used for statistical analysis.

RESULTS

Two-way ANOVA demonstrated significant differences between remineralizing agents and time points. After 4 weeks, the SAP (P_11-4) group had had significantly higher Ca/P ratio and SMH (1.68±0.11 and 346.47±55.38) compared to other groups, followed by CPP-ACPF (1.52±0.19 and 283.53±64.75), FV (1.37±0.14 and 262.80±82.98), and the control group (1.31±0.10 and 213.00±41.95). Significantly higher Ca/P ratio and SMH were observed at 2 weeks in the control group (1.44±0.10 and 269.63±57.37) and FV group (1.52±0.09 and 321.17±55.24) compared to 4 weeks. No significant differences were found regarding Ca/P ratio and SMH at 2 weeks in the CPP-ACPF (1.55±0.15 and 295.14±53.88) and SAP P_11-4 groups (1.64±0.10 and 320.18±58.04) compared to 4 weeks.

CONCLUSION

SAP (P_11-4) had the greatest remineralizing efficacy compared to FV and CPP-ACPF. Moreover, extended period of time improved the preventive efficacy of SAP (P_11-4) compared to the other regimens.

Efficacy of Fluoride Varnish with Casein Phosphopeptide and Amorphous Calcium Phosphate vs Fluoride Varnish in Prevention of White Spots Lesion in fixed Orthodontic Patients: In Vivo Study

AIM

The aim of the study is to compare the in vivo efficiency of Michigan (MI) varnish containing casein phosphopeptide (CPP) and amorphous calcium phosphate (ACP) and Fluoritop containing sodium fluoride (5% NaF) in the prevention and remineralization of white spot lesions (WSLs) around orthodontic brackets at days 28 and 56 after bonding.

MATERIALS AND METHODS

A total of 30 patients were selected and divided into two groups I (MI varnish) II (Fluoritop varnish) of 15 patients in each group. All the patients were bonded and then varnish was applied around the brackets. Right-side upper and lower first premolar teeth were taken as the control group and left-side upper and lower first premolar teeth as the experimental group. Also, 14, 24 teeth were extracted on day 28 after bonding and 34, 44 teeth after day 56 of bonding. Samples were collected and sent to laboratory for evaluation of surface microhardness (SMH).

RESULTS

Based on the statistics results, there was a significant decrease in demineralization and an increase in remineralization of WSLs after the application of varnish. No statistical significance was found between the effectiveness of MI varnish and Fluoritop except in the cervical region.

CONCLUSION

Through our study, we concluded that no statistical significance was found between the effectiveness of MI varnish and Fluoritop except in the cervical region where MI varnish was found to be more effective than Fluoritop in preventing WSLs.

CLINICAL SIGNIFICANCE

The results from the above study concluded that CPP-ACP varnish can be an effective method in preventing WSLs in patients undergoing fixed orthodontic treatment.

Bioactive Inorganic Materials for Dental Applications: A Narrative Review

Over time, much attention has been given to the use of bioceramics for biomedical applications; however, the recent trend has been gaining traction to apply these materials for dental restorations. The bioceramics (mainly bioactive) are exceptionally biocompatible and possess excellent bioactive and biological properties due to their similar chemical composition to human hard tissues. However, concern has been noticed related to their mechanical properties. All dental materials based on bioactive materials must be biocompatible, long-lasting, mechanically strong enough to bear the masticatory and functional load, wear-resistant, easily manipulated, and implanted. This review article presents the basic structure, properties, and dental applications of different bioactive materials i.e., amorphous calcium phosphate, hydroxyapatite, tri-calcium phosphate, mono-calcium phosphate, calcium silicate, and bioactive glass. The advantageous properties and limitations of these materials are also discussed. In the end, future directions and proposals are given to improve the physical and mechanical properties of bioactive materials-based dental materials.

Comparison of Remineralization Potential of Casein Phosphopeptide: Amorphous Calcium Phosphate, Nano-hydroxyapatite and Calcium Sucrose Phosphate on Artificial Enamel Lesions: An In Vitro Study

Aim and objective

To evaluate and compare the remineralization potential of CPP-ACP, nano-hydroxyapatite, and calcium sucrose phosphate toothpaste on artificial enamel caries lesions by means of microhardness testing.

Materials and methods

Twenty sound human primary molars, extracted for therapeutic reasons were selected for this study. From each tooth, two enamel specimens were prepared and embedded in acrylic resin blocks, and each block contains five tooth samples. After polishing, the baseline hardness of the enamel surface (KHN) was determined by Knoop microhardness testing. Then the specimens were randomly assigned into four groups (n = 10), according to the remineralizing agent used: group I: Control, group II: GC Tooth Mousse^TM (CCP-ACP), group III: Acclaim^TM (nano-HAP), and group IV: EnaFix (CaSP). The specimens were then immersed in a demineralizing solution and post-lesion KHN values were obtained as baseline measurements. Later remineralizing agent was applied and after 7 days of remineralization, posttreatment KHN tests were conducted.

Results

Data were analyzed using paired t- test, analysis of variance, and Tukey HSD test. Mean enamel surface microhardness (KHN) values after remineralization shows that group IV (EnaFix^TM) had maximum hardness number (114.71 ± 12.27) followed by group III (Acclaim) (85.14 ± 22.82) and group II (GC Tooth Mousse) (56.42 ± 19.90). The difference was statistically significant (p < 0.001). Similarly the %SMHR was also highest in group IV (EnaFix), followed by group III (Acclaim) and group II (GC Tooth Mousse).

Conclusion

EnaFix (calcium sucrose phosphate) shows a maximum increase in the enamel surface microhardness followed by Acclaim (nano-HAP) and GC Tooth Mousse.

Clinical significance

Calcium Sucrose Phosphate in toothpaste strengthened the enamel more than nano hydroxyapatite and CPP-ACP, and can be an alternative to the use of fluoride toothpaste in children.

How to cite this article

Sebastian R, Paul ST, Azher U, et al. Comparison of Remineralization Potential of Casein Phosphopeptide: Amorphous Calcium Phosphate Nano-hydroxyapatite and Calcium Sucrose Phosphate on Artificial Enamel Lesions: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(1):69-73.

Impact of direct restorative dental materials on surface root caries treatment. Evidence based and current materials development: A systematic review

This systematic review provides an update on the development and efficacy of direct restorative dental materials for root caries interventions from in vitro and clinical studies. PubMed, Embase, and Web of Science were searched using specific MeSH keywords. Full articles from September 1990 to October 2021 were collected. Additional articles were identified by reference retrieval and manual searching. Studies not related to restorative materials for root caries treatment, case reports, non-original articles, and/or articles not written in English were excluded. Bias risk assessment was performed for the clinical studies. Forty-two articles (eleven clinical studies and thirty-one in vitro studies) were included for analysis. Most in vitro studies indicated an excellent cariostatic effect of glass ionomer cement. Resin-modified glass ionomer restorations also presented reduced recurrent caries activity but had a lower efficacy than glass ionomer cement restorations. For composite resin restorations, the main material development strategies are to strengthen the tooth structure and integrate antimicrobial activity. The clinical studies offered limited data, so the most appropriate material for surface root caries treatment is still inconclusive. However, atraumatic restorative treatment (ART) is an alternative treatment for patients with limiting conditions. Further clinical studies are required to confirm the efficacy of bioactive materials.

Bioactive remineralization of dentin surface with calcium phosphate-based agents: An in vitro analysis

Background:

With the increasing prevalence of erosive tooth wear affecting both adults and children; designing optimum protocols of management in a noninvasive manner is gaining precedence.

Aim:

Comparative evaluation of topically applied calcium phosphate-based agents casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and beta tricalcium phosphate (β-TCP) on the surface of eroded dentin.

Materials and Methods:

Dentin blocks from human third molars in four groups were subjected to the surface treatment: (G1) sound dentin (G2) demineralized dentin (G3) CPP-ACP (G4) β-TCP. All the samples except control (G1) were immersed in an acidic solution incubated at 37°C for 96 h. The samples in G3 and G4 were topically treated with CPP-ACP and β-TCP for 4 min twice daily for 14 days; followed by pH-cycling for 21 days. Surface hardness testing and surface morphology were observed using the scanning electron microscopy. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) software with Kruskal-Wallis test and post hoc test.

Results:

Dentin treated with both CPP-ACP (37.25) and β-TCP (32.05) recorded significantly higher VHN than demineralized (G2-23.51) but lower compared to sound control (G1-57.06).

Conclusion:

The topical application of CPP-ACP and β-TCP agents shows definite potential in promoting the hardening of demineralized dentin surface.

Comparative evaluation of remineralizing effect of fluoride and nonfluoride agents on artificially induced caries using different advanced imaging techniques

Aim:

The aim of the study is to evaluate and compare the in-vitro remineralization efficacy of remineralizing agents, i.e., fluoride-free toothpaste, fluoride toothpaste, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), CPP-amorphous calcium fluoride phosphate (CPP ACFP), and silver diamine fluoride (SDF) paste on dentine over time.

Methodology:

Seventy-five extracted human permanent molars were selected. The buccal section of these samples was shaped into a slab. Artificial caries was induced by dipping the samples into the demineralizing solution (pH 4.5) for 21 days. They were then divided into five groups (n = 15). Each experimental group underwent one of the following treatments: Group 1 – Fluoride-free toothpaste (negative control), Group 2 – Fluoride toothpaste (positive control), Group 3 – CPP-ACP, Group 4 – CPP-Amorphous Calcium fluoride Phosphate and Group 5 – SDF. Postremineralizing treatment, Scanning electron microscope, Energy dispersive X-ray and Quantitative light induced fluorescence imaging were carried out to analyze the remineralizing efficacy. The data obtained was then subjected to statistical analysis using ANOVA and Paired t-tests.

Results:

It was seen that SDF showed highest remineralization efficacy followed by CPP-amorphous calcium fluoride phosphate, CPP-ACP, fluoride toothpaste and fluoride-free toothpaste. The difference in mean value among the groups was statistically significant (P < 0.001).

Conclusion:

SDF showed the highest remineralizing potential in scanning electron microscopy and energy dispersive X-ray, followed by CPP-ACFP, CPP-ACP, Fluoride toothpaste, and Fluoride-free toothpaste. Quantitative light fluorescence analysis showed more fluorescence changes in the CPP-ACFP followed by CPP-ACP, Fluoride toothpaste, and Fluoride-free toothpaste.

Effects of desensitizing dentifrices on dentin tubule occlusion and resistance to erosive challenges

Background

Many studies have demonstrated efficacy of casein phosphopeptide (CPP) containing products for dentin tubule occlusion for treatment of dentin sensitivity, but their effectiveness under dynamic erosive challenges remains to be elucidated. The purpose of the present study was to investigate the effectiveness of a desensitizing dentifrice containing CPP in occluding dentin tubules and resisting erosive challenges in comparison to that containing polyvinyl methyl ether/maleic acid (PVM/MA) copolymers.

Methods

A total of 33 dentin discs were prepared from coronal sections of human third molars and divided into 3 groups: a toothpaste containing CPP; a toothpaste containing PVM/MA and submicron silica; and a regular toothpaste (Controls). A soft-bristle toothbrush was used to brush the dentin discs with the dentifrices for 45 strokes in 30 s at a force of approximately 200 g. The brushing cycle was repeated after immersion of the dentin discs in artificial saliva overnight. The dentin discs were then challenged in orange juice for 10 min in an incubator rocking at 120 rpm. Three fields were randomly selected on each dentin disk surface to assess dentin tubule occlusions after each brushing cycle and after orange juice challenge with a 3D laser scanning microscope. Specimen cross sections were examined with a scanning electron microscope equipped with energy dispersive spectroscopy (SEM/EDS).

Results

After the first and second cycles of brushing, dentin tubules were occluded on average by 56.3% and 85.7% in CPP group, 66.2% and 88.1% in PVM/MA group, and 0.0 and 13.0% in the controls, respectively. There were no statistically significant differences in dentin tubule occlusions between the CPP and PVM/MA groups after two cycles of brushing (p>0.05). After dynamic erosive challenges with orange juice, 20.3% of the dentin tubules in the CPP group, 79.1% in the PVM/MA group and none in the control remained occluded (P<0.05). SEM/EDS imaging showed that dentin tubules were blocked with plugs containing dentifrice substances in CPP and PVM/MA groups after treatments, but none in the controls.

Conclusions

Desensitizing dentifrices containing CPP or PVM/MA could effectively occlude dentin tubules after two cycles of brushing. PVM/MA in combination with submicron silicon dioxide exhibited stronger resistance to dynamic erosive challenges by acidic beverages. Inorganic fillers that can enter dentin tubules and resist erosive challenges may be key for desensitizing dentifrices.

Synthetic amorphous calcium phosphates (ACPs): preparation, structure, properties, and biomedical applications

Amorphous calcium phosphates (ACPs) represent a metastable amorphous state of other calcium orthophosphates (abbreviated as CaPO₄) possessing variable compositional but rather identical glass-like physical properties, in which there are neither translational nor orientational long-range orders of the atomic positions. In nature, ACPs of a biological origin are found in the calcified tissues of mammals, some parts of primitive organisms, as well as in the mammalian milk. Manmade ACPs can be synthesized in a laboratory by various methods including wet-chemical precipitation, in which they are the first solid phases, precipitated after a rapid mixing of aqueous solutions containing dissolved ions of Ca²⁺ and PO₄^3- in sufficient amounts. Due to the amorphous nature, all types of synthetic ACPs appear to be thermodynamically unstable and, unless stored in dry conditions or doped by stabilizers, they tend to transform spontaneously to crystalline CaPO₄, mainly to ones with an apatitic structure. This intrinsic metastability of the ACPs is of a great biological relevance. In particular, the initiating role that metastable ACPs play in matrix vesicle biomineralization raises their importance from a mere laboratory curiosity to that of a reasonable key intermediate in skeletal calcifications. In addition, synthetic ACPs appear to be very promising biomaterials both for manufacturing artificial bone grafts and for dental applications. In this review, the current knowledge on the occurrence, structural design, chemical composition, preparation, properties, and biomedical applications of the synthetic ACPs have been summarized.

An Eggshell-Based Toothpaste as a Cost-Effective Treatment of Dentin Hypersensitivity

Objectives This study aimed to test the efficacy of two experimentally produced eggshell-based toothpastes on dentinal tubules occlusion.

Materials and Methods Two experimental eggshell toothpastes, based on natural ingredients, with or without titanium dioxide nanoparticles (TNPs) were produced and coded “TNPs eggshell toothpaste [TNPsESTP]” or “eggshell toothpaste [ESTP],” respectively. Mid-coronal dentin discs, from 28 human extracted molar teeth, etched with 37% phosphoric acid for 60 seconds to simulate the hypersensitive dentin, were randomly divided into four groups—G1: no treatment (negative control), G2: ESTP treated, G3: TNPsESTP treated, and G4: Biorepair treated (positive control). All treated discs were brushed for 2 weeks and 1 month using a toothbrush simulator at 40 mm/s. Dentinal tubules occlusion was studied using a cross-polarization optical coherence tomography (CP-OCT) and scanning electron microscopy (SEM).

Statistical Analysis Unpaired t -test was conducted using GraphPad software (San Diego, California, United States). Continuous variables were expressed as means ± standard deviation and p < 0.05 was considered statistically significant.

Results From CP-OCT, a marked increase in surface reflectivity of dentin was observed after brushing with tested toothpastes. ESTP and NPsESTP showed higher or comparable grayscale values than Biorepair indicating increase in surface density of dentin. From SEM, at 2 weeks, ESTP showed comparable number of completely occluded dentinal tubules to Biorepair. TNPsESTP showed significantly lower numbers of CODT than Biorepair. At 1 month, the number of CODT was difficult to count for all treated groups. Both ESTP and TNPsESTP showed significantly higher numbers of partially occluded dentinal tubules than Biorepair.

Conclusion ESTP or TNPsESTP could offer a cost-effective substitute for the treatment of dentin hypersensitivity.

Effectiveness of CPP-ACP and Fluoride Products in Tooth Remineralization

OBJECTIVES

To compare the effectiveness of the casein phosphopeptide-stabilized amorphous calcium phosphate (CPP-ACP) in the in situ remineralization of enamel exposed to two different degrees of preformed enamel lesions.

METHODS

One hundred and sixty 3x3x2 mm human enamel slabs were demineralized and divided into two subgroups according to baseline surface hardness (SH=B1≤150 and B2 >150). During each of four 10-day experimental periods, 10 participants wore intraoral removable acrylic palatal expanders with four human enamel slabs with preformed lesions (B1 and B2): CO1 and CO2 - Control: silica dentifrice without fluoride; MP1 and MP2: MI Paste; MPP1 and MPP2: MI Paste Plus; and FD1 and FD2: Fluoride dentifrice. The Knoop hardness test (50/15s Micromet 2001, Buehler, IL, USA) was performed after demineralization (B1 and B2) and after treatment (T1 and T2).

RESULTS

SH was higher in all treatment groups when compared with the controls, except for CO2 (Mann Whitney Wilcoxon Test; p <0.05). %SH was similar between MPP2 and FD2 and between MPP2 and MP2; however, FD2 and MPP2 products were more effective in microhardness recovery. In B1, all treatment groups were similar.

CONCLUSION

MPP and FD are more effective in preventing demineralization in enamel subsurface lesions.

The color improvement of postdebonding white spot lesions after fluoride and casein phosphopeptide- amorphous calcium phosphate application

White spots are common side effects of orthodontic treatment, and their presence after debonding appears unesthetic. This study aimed to quantify and compare the visual improvement in postdebonding white spot lesions following fluoride and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application. The sample included 42 upper premolars extracted for orthodontic reasons. Universal premolar brackets were bonded to the facial surfaces of the teeth that were exposed to a demineralization solution to create artificial white spot lesions, after which the brackets were debonded. The specimens were randomly allocated to three treatment groups (n = 14, each): acidulated phosphate fluoride (APF) gel application group; CPP-ACP paste application group; and control group. pH cycling was conducted to all groups for 14 days. Quantitative measurements were carried out using a spectrophotometer at the following times: before and after the white spot lesions artificially formed and after treating them. All groups showed significant differences in color change before and after treatment. However, there was no significant difference in the color improvement between the APF gel and CPP-ACP paste application groups. Although CPP-ACP application improved the color of the white spot lesions, it did not differ significantly from that of fluoride application.

Preparation and Characterization of Instant Casein Phosphopeptide by Supercritical Fluid Assisted Atomization

Casein phosphopeptide (CPP) has been widely used as micronutrient supplementation for certain populations. However, its solubility performance is far from satisfying. In this work, instant CPP powders with micropore structures were fabricated by supercritical fluid-assisted atomization (SAA) using supercritical CO₂ fluid (SC-CO₂) as an atomizing agent. The effects of the processing parameters (temperature, time, and pressure) on SC-CO₂ absorption rate and dissolution rate were systematically evaluated and studied. The viscosity of the CPP solution increased with increased pressure of SC-CO₂ as pressure increased its solubility. The processing conditions are optimized as follows: 40 °C, 40 min, and 8.27 MPa, with an SC-CO₂ absorption rate of about 8 wt.%. The dissolution time of the SAA-CPP powders was significantly decreased from 1800 s to 54 s at room temperature, due to the micropore structures and almost 10 times increase in the specific surface area of SAA-CPP. The bioactivities of the instant SAA-CPP, especially the calcium-binding capacity, were also evaluated and showed no observable difference. Among the four CPPs prepared in different ways in this work, SAA-CPP had better dissolution performance. The results show that SAA technology is a promising way to prepare instant polypeptide powders.

Enamel demineralization model in primary teeth: Micro-CT and SEM assessments of artificial incipient lesion

Many studies have analyzed different tooth demineralization models, which generate artificial incipient lesions; however, most of them are complex, slow, not clear and results could not be employed in both primary and permanent teeth because of chemical content differences among them. This study evaluates a demineralization model on primary enamel, under three incubation periods; quantifying artificial incipient lesions formation, and depth by micro-CT, complementing with SEM for morphological characterization. Sixteen healthy human anterior primary teeth extracted for prolonged retention and orthopedic/orthodontic reasons were included in this study, previous informed consent. The sample was randomly assigned to four groups n = 4: G_Control, G_2D, G_4D, and G_7D. Micro-CT and SEM were performed during two stages: before demineralization (BD) and after demineralization (AD). A t-student test was carried out to determine differences among groups (p ≤ .05). No incipient lesions were observed in control group. Artificial lesion depth was similar among experimental groups; values were from 38.16 ± 05.40 μm to 42.61 ± 04.75 μm. An amount of 14 to 17 artificial incipient lesions were formed per group, the extension and distribution were different for each incubation period. Five erosive lesions were produced in G_7D. All experimental groups were able to form incipient artificial lesions in primary enamel. SEM characterization revealed more pronounced changes on the enamel surface, as the days of immersion in the demineralization solution increased. The 4-day incubation period is the most recommended for the demineralization model, due to the formation of incipient lesions only and its extension, which facilitates their assessment.

In vitro remineralization of enamel with a solution containing casein and fluoride

The aim of the present study was to investigate the effects of casein in a remineralization solution on enamel remineralization. Bovine blocks were demineralized for 21 days, then, allocated into four groups. The specimens were remineralized for 21 days in the following artificial saliva solutions: 1) 0 µg/mL casein, 0 ppm fluoride (F) (C0-F0); 2) 0 µg/mL casein, 1 ppm F (C0-F1); 3) 10 µg/mL casein, 0 ppm F (C10-F0); and 4) 10 µg/mL casein, 1 ppm F (C10-F1). Micro-CT analyses were performed once a week. Specimens were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The present results suggest that casein by itself inhibits remineralization, whereas the coexistence of casein and F promotes the remineralization of caries bodies by interrupting mineral deposition on the enamel surface.

Remineralization Potential of Nanohydroxyapatite Toothpaste Compared with Tricalcium Phosphate and Fluoride Toothpaste on Artificial Carious Lesions

Introduction

Nanohydroxyapatite (nano-HA) has been utilized as an alternative agent for dental enamel remineralization. This study compared remineralization potential of nano-HA toothpaste (NHT), functionalized tricalcium phosphate toothpaste (TCPT), and fluoride toothpaste (FT) on carious lesions.

Materials and Methods

Sixty extracted human premolars were prepared for artificial carious lesions with synthetic polymer gel. Samples were divided into four groups according to testing agents: NHT, TCPT, FT, and one group with no treatment (NT). Each group was subjected to pH-cycling with the application of toothpaste in slurry form twice a day (2-min each) for 10 days. Surface microhardness was measured before demineralization, after demineralization, and after pH-cycling. Hardness at different periods, percentage of hardness recovery (% HR), and percentage of remineralization potential (%RP) were determined and statistically analyzed with ANOVA and Tukey comparisons (α = 0.05). Polarized light microscopy (PLM) was utilized to assess lesion depth.

Results

Significant remineralization of carious lesions was observed among different toothpastes compared to NT (p < 0.05). No significant difference in remineralization potential was found among NHT, TCPT, and FT (p > 0.05). No significant difference in % HR and % RP was seen among NHT, TCPT, and FT (p > 0.05). PLM indicated a greater decrease in carious depth upon using NHT compared to TCPT and FT, with minimal increase in depth for NT.

Conclusions

NHT has comparable capability to TCPT and FT in hardness recovery. However, decrease in carious depth was evidenced with PLM for NHT more than TCPT and FT. Thus, NHT was suggested as a potential remineralization product for treating initial carious lesions. Clinical Significance. The study showed that NHT had the potential to remineralize artificial carious lesion. It was confirmed in potential in the lesion depth reduction and forming a new enamel layer. NHT showed its capability as an alternative for dental caries therapeutic.

Ion release and recharge from a fissure sealant containing amorphous calcium phosphate

To assess- the release of calcium and phosphate ions from a fissure sealant containing amorphous calcium phosphate (ACP), and to determine the re-release capacity of these ions when charged with a solution containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP). Nine blocks of ACP resin-based sealant were prepared and immersed in three solutions at different pH (4.0, 5.5, 7.0), and calcium and phosphate ion release was measured with ion chromatography at 1, 3, 5, 7, 14, 21 and 28 days after immersion. Sixty days after immersion, each block was charged with CPP-ACP solution in three 7-day cycles to investigate the re-release of these ions, which was measured on days 1, 3, and 7. No difference was observed in initial calcium ion release at pH 4.0 and pH 5.5. At both values, ion release was significantly higher than at pH 7.0 (p<0.001). Initial phosphate release was significantly different among the three pH values (p<0.001). After re-charging the specimens, calcium ion re-release was greater than phosphate ion release. Initial ion release from ACP resin-based sealant was greatest at the lowest pH. Ion release decreased with time. As the number of recharge cycles increased, ion re-release also improved. Phosphate ion re-release required more recharge cycles than calcium ion re-release.

Comparison of the Remineralizing Effect of Brushing with Aloe vera versus Fluoride Toothpaste

Objectives  The aim of the present in vitro study is to compare the remineralization brushing effect of three toothpastes and Aloe vera (AV) gel.

Materials and Methods  Forty sound extracted teeth were placed in a demineralizing solution for 4 days and randomly assigned to four groups: group A: 1,450-ppm fluoride toothpaste; group B: AV nonfluoridated toothpaste; group C: AV 1,000-ppm fluoridated toothpaste; and group D: AV gel. A 3-minute pH cycling was performed twice a day for each group for 12 days. Specimens were analyzed before and after by scanning electron microscope—energy dispersive X-ray.

Statistical Analysis  The outcomes were analyzed by Kolmogorov–Smirnov’s tests, repeated-measures analyses of variance followed by univariate analyses, and Bonferroni’s multiple comparisons tests to compare the calcium-to-phosphorus (Ca:P) ratio within time among toothpaste groups.

Results  Following remineralization, the Ca:P ratio increased in all groups. The difference of the Ca:P ratio was not significant between groups C, D, and A. The mean ratio was significantly lower in group B ( p -value = 0.026).

Conclusions  The AV gel demonstrated a remineralization capacity equal to that of the 1,450-ppm fluoride toothpaste. In contrast, fluoride-free AV toothpaste showed a lower remineralization efficiency. Further studies are required to understand its mechanism.

The Efficacy of Resin Infiltrant and Casein Phosphopeptide-amorphous Calcium Fluoride Phosphate in Treatment of White Spot Lesions (Comparative Study)

Background:

White spot lesions (WSLs) are considered as the first sign of the progression of dental caries that can be reversed. Casein phosphopeptide–amorphous calcium fluoride phosphate (CPP-ACFP) varnish can promote remineralization process of the demineralized tooth structure. Also, WSLs can be managed by using caries infiltrant (ICON), which infiltrates etched enamel surface of the WSLs.

Objectives:

The main aim was to evaluate and compare the efficacy of ICON versus CPP-ACFP varnish to treat WSLs in the same oral environments.

Materials and Methods:

A total of 30 participants aged 20–40 years with at least two WSLs have participated in this trial. Split-mouth technique has been used in this trial where WSLs on the left side have been treated with ICON, whereas WSLs on the right side have been treated with CPP-ACFP varnish. Clinical evaluation using DIAGNOdent was carried out at baseline, 1 week, 1, 3, 6, and 12 months after application to determine the effectiveness of these materials in treating WSLs.

Results:

Significant differences were observed between all follow-up DIAGNOdent scores compared to baseline readings of both ICON and CPP-ACFP (P = 0.000 for all comparisons). Statistically significant differences were observed between DIAGNOdent scores of ICON compared to CPP-ACFP at all follow-up intervals (P = 0.006, 0.008, 0.045, 0.036, and 0.000).

Conclusion:

Both ICON and CPP-ACFP were effective in the treatment of WSLs of smooth surfaces but the efficacy of CPP-ACFP was better than ICON.

Comparative evaluation of remineralization potential of nanohydroxyapatite crystals, bioactive glass, casein phosphopeptide-amorphous calcium phosphate, and fluoride on initial enamel lesion (scanning electron microscope analysis) - An in vitro study

Aim:

The aim of this in vitro study was to evaluate and compare the remineralization potential of four different remineralizing agents, i.e., nanohydroxyapatite crystals, bioactive glass, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and fluoride on initial enamel lesion.

Materials and Methods:

Sixty human maxillary central incisors were used in the present study. Samples were randomly divided into four groups (n = 15). Group 1: nanohydroxyapatite-containing dentifrice (Acclaim); Group 2: bioactive glass containing-dentifrice (SHY-NM); Group 3: CPP-ACP-containing dentifrice; and Group 4: fluoride-containing dentifrice. Baseline microhardness was checked, followed by immersion of teeth samples in demineralizing and remineralizing solution. This was followed by a pH cycle of 10 days. Data were analyzed using ANOVA and Bonferroni method. After this, scanning electron microscopic analysis was done to evaluate remineralization.

Results:

Statistical analysis of data was conducted using ANOVA, and multiple comparisons within groups were done using the Bonferroni method (post hoc tests). The decision criterion was to reject the null hypothesis if P < 0.05. If there was a significant difference between the groups, multiple comparisons (post hoc test) using the Bonferroni test were carried out.

Conclusion:

There is a significant difference in mean microhardness between the groups after remineralization. The mean value was found to be highest for nanohydroxyapatite, bioactive glass, CPP-ACP, and fluoride in descending order.

Enamel Subsurface Caries-Like Lesions Induced in Human Teeth By Different Solutions: A TMR Analysis

This study assessed the effectiveness of models for developing subsurface caries lesions in vitro and verified mineral changes by transverse microradiography (TMR). Enamel blocks from permanent (n=5) and deciduous teeth (n=5) were submitted to lesion induction by immersion in demineralizing solutions during 96 h, followed by pH cycles of demineralization (de) and remineralization (re) for 10 days. Two de-/re solutions were tested. Demineralizing solution "A" was composed by 2.2 mM CaCl2, 2.2 mM KH2PO4, 0.05 M acetic acid, with pH 4.4 adjusted by 1 M KOH. Demineralizing solution "B" was composed by 2.2 mM CaCl2, 2.2 mM NaH2PO4, 0.05 M acetic acid and 0.25 ppmF, with pH 4.5 adjusted by 1M KOH. Solution "A" produced cavitated lesions in permanent teeth, whereas solution "B" led to subsurface lesions in deciduous teeth. Solution "B" was then tested in enamel blocks from permanent teeth (n=5) and subsurface lesions were obtained, so that solution "B" was employed for both substrates, and the blocks were treated with slurries of a fluoride dentifrice (1450 ppm F, as NaF, n=5) or a fluoride-free dentifrice (n=5). Solution "B" produced subsurface lesions in permanent and primary teeth of an average (±SD) depth of 88.4µm (±14.3) and 89.3µm (±15.8), respectively. TMR analysis demonstrated that lesions treated with fluoride-free dentifrice had significantly greater mineral loss. This study concluded that solution "B" developed subsurface lesions after pH cycling, and that mineral changes were successfully assessed by TMR.

Complementary remineralizing effect of self-assembling peptide (P11-4) with CPP-ACPF or fluoride: An in vitro study

Background

Self-assembling peptide has been recently introduced to promote hard tissue regeneration for treating early non-cavitated carious lesions. This study investigates the efficacy of biomimetic self-assembling peptide (P11-4) on enamel remineralization combined with CPP-ACPF or fluoride.

Material and Methods

Artificial enamel lesions were created on buccal surface of 60 specimens and were randomly assigned to six groups according to the remineralizing agent: G1-(Control, artificial saliva), G2-(Fluoride varnish), G3-(CPP-ACPF varnish), G4-(Self-assembling peptide), G5-(Self-assembling peptide+fluoride varnish), G6-(Self-assembling peptide+CPP-ACPF varnish). All products were applied according to manufacturer’s instructions and specimens were stored in a daily renewed artificial saliva. Surface microhardness (SMH) and scanning electron microscope (SEM) were assessed at baseline, after demineralization, 1 week and 4 weeks storage. SMH values were analyzed using ANOVA and Tukey’s post-hoc test.

Results

The highest statistically significant SMH values were found in G6 followed by G5, G4, G2 and G3 while the lowest values were found in G1. No statistically significant difference was found between G5 and G6. Also, no statistically significant difference was found between G2 and G3. SEM showed that G4, G5, G6 resulted in more pronounced remineralization, reversing the demineralized enamel fish scale pattern compared to G2 and G3 after 1 week and 4 week remineralization.

Conclusions

Complementary effect was obtained after combining self-assembling peptide with CPP-ACPF or fluoride showing the highest remineralizing potential early after 1 week and even after 4 weeks compared to when each agent used alone. Added benefits can be obtained through combining self-assembling peptide with other remineralzing agents allowing faster and enhanced regeneration of non-cavitated caries lesions.

Key words:Enamel regeneration, biomimetic remineralization, self-assembling peptide, CPP-ACPF, fluoride.

Effect of CO2 laser (10.6 μm) and Remin Pro on microhardness of enamel white spot lesions

This study investigated the combined effect of CO₂ laser irradiation and Remin Pro paste on microhardness of enamel white spot lesions (WSLs). Seventy-eight intact premolars were randomly assigned into six groups and then stored in a demineralizing solution to create WSLs. Afterwards, the teeth in group 6 (negative control) remained untreated, while groups 1 and 4 were exposed to CO₂ laser irradiation (20 Hz, 1 W, 30 s) and Remin Pro paste, respectively. In groups 2 and 3, the teeth were exposed to laser either before (group 2) or after (group 3) Remin Pro application. The teeth in groups 1 to 5 were then immersed in artificial saliva for 90 days while subjected to fluoride mouthwash and weekly brushing. Finally, the teeth were sectioned, and Vickers microhardness was measured at the enamel surface and at 50, 100, and 150 μm from the surface. One sample of each group was also examined with scanning electron microscope (SEM). Data were analyzed by two-way analysis of variance (ANOVA) and Tukey's test. The significance was set at 0.05. Laser irradiation followed by Remin Pro application (group 2) caused a significant increase in total WSLs' microhardness compared with laser alone (group 1) and control groups (P < 0.05). Microhardness at depths of 100 and 150 μm was also significantly greater in group 2 compared with those of group 3 and control groups (P < 0.05). Combined application of CO₂ laser with Remin Pro paste, when laser is irradiated before the paste, is suggested for re-hardening of WSLs in deep layers of enamel.

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.

Effectiveness of polyacrylic acid-bioactive glass air abrasion preconditioning with NovaMin remineralization on the microhardness of incipient enamel-like lesion

Background:

Bioactive glass (BAG) remineralization is a promising method for dental hard tissue regeneration. The aim of this study was to evaluate the microhardness of incipient enamel-like lesions with or without preconditioning by air abrasion using polyacrylic acid (PAA)-BAG before application of NovaMin remineralizing agent.

Materials and Methods:

Forty extracted human molars were selected, sectioned mesiodistally obtaining buccal and lingual halves, and embedded in resin molds. Specimens were randomly assigned to four groups (n = 10) according to the remineralization protocol: G1 (control, artificial saliva), G2 (preconditioning), G3 (NovaMin), and G4 (preconditioning and NovaMin). Enamel windows 4 mm × 4 mm were done on the buccal and lingual surfaces. Specimens were immersed in a daily renewed demineralizing solution to create white spot lesions. Remineralizing agents were applied according to the manufacturer's instructions, and specimens were stored in a daily renewed artificial saliva. Microhardness was assessed using Vickers hardness number (VHN) at baseline (positive control), after demineralization (negative control), and after 24-h and 1-month remineralization.

Results:

The preconditioning/NovaMin group after 1 month showed a statistically significant high VHN, with no statistically significant difference between it and the positive control. This was followed by the NovaMin group after 1 month, while the lowest VHN was found in the demineralized group, with no statistically significant difference between it and the preconditioning group, whether after 24 h or 1 month.

Conclusions:

Enamel preconditioning with PAA-BAG air abrasion play a major role in enhancement of remineralization when it is accompanied with NovaMin. Furthermore, an extended period of time had helped to attain more benefits from NovaMin remineralization.

Clinical Significance:

Enamel remineralization with NovaMin after conditioning by bioactive glass air abrasion, provides the patients with a fast and durable treatment of incipient enamel lesions, which would reduce the possibility of future progression of demineralization and caries occurrence.

Assessment of the resin infiltration and CPP-ACP applications before orthodontic brackets bonding

The aim of this study is to investigate the efficiency of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) gel and resin infiltrant on decalcified enamel, and to explain the correlation, if any, between ion release capacities and shear bond strength (SBS). A total of 80 premolar teeth were used (n=20). Group I was the control, while a demineralization protocol was performed for other groups. CPP-ACP gel and resin infiltrant, respectively, was applied to Groups III and IV. Pre and post-demineralization energy dispersive X-Ray analysis of all groups and post-application of Groups III and IV were undertaken. SBS tests were performed. Ca/P ratio significantly increased after the applications. Both agent groups showed a significant decrease in SBS values compared to others. There was no correlation between SBS and Ca/P ratio changes. It can be said that CPP-ACP and resin infiltrant therapies enhance the tooth mineral content, but show lesser SBS values than the control and demineralization only groups.

Efficacy of erbium-doped yttrium aluminum garnet laser with casein phosphopeptide amorphous calcium phosphate with and without fluoride for remineralization of white spot lesions around orthodontic brackets

Objective

This study aimed to assess the efficacy of erbium-doped yttrium aluminum garnet (Er:YAG) laser, pastes containing casein phosphopeptide amorphous calcium phosphate (CPP-ACP) with and without fluoride and their combination for prevention of white spot lesions in the enamel.

Materials and Methods

This in vitro experimental study was conducted on 90 extracted sound premolars. The teeth were then randomly divided into six groups of 15: (1) Control, (2) laser, (3) CPP-ACP with fluoride (GC MI Paste, Recaldent™ 900 ppm as NaF), (4) CPP-ACP without fluoride (GC Tooth Mousse Recaldent™), (5) laser + CPP-ACP with fluoride, and (6) laser + CPP-ACP without fluoride. In each group, enamel surface was exposed to the remineralizing agent. The teeth were then subjected to pH cycling for 14 days. The teeth were then sectioned, polished, and underwent cross-sectional microhardness testing at 20-160 μ depth quantitatively. Using the Simpson's rule, the amount of mineral loss was calculated in each group. Statistical Analysis Used: ANOVA was used for the comparisons, and Tukey's test was applied for pairwise comparisons.

Results

The highest mean volume percentage of microhardness at 20-60 μ depth belonged to the group laser + CPP-ACP with fluoride and the lowest belonged to the control group (P = 0.001). The differences were not significant at 80-120 μ depth (P > 0.05). These finding are confirmed according to △Z (mineral loss).

Conclusion

Based on these results, Er: YAG laser was able to decrease demineralization and was a potential alternative to preventive dentistry and was more effective when combined with CPP-ACP products.

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.

Bleaching gel mixed with MI Paste Plus reduces penetration of H2O2 and damage to pulp tissue and maintains bleaching effectiveness

OBJECTIVES

MI Paste Plus remineralizer (Rem) strengthens dental structures after bleaching. We investigated the effect of Rem on the penetration of hydrogen peroxide (H₂O₂), bleaching effectiveness, and pulp inflammation after bleaching.

MATERIALS AND METHODS

Bovine disks were grouped as follows (n = 10): control (untreated), bleached (Ble; 35% H₂O₂, 30 min), Ble-Rem (H₂O₂ followed by Rem, 30 min), Rem-Ble (Rem followed by H₂O₂), Rem-Ble-Rem (Rem before and after H₂O₂), and Ble+Rem (mixture of Rem with H₂O₂, 1:1, 30 min). The penetration of H₂O₂ was quantified and bleaching efficacy was analyzed. Upper rat molars (n = 10) received the same treatments at random. The rats were euthanized after two days and 30 days, and their jaws were removed for histological analysis. Statistical tests were performed (P < 0.05).

RESULTS

The bleached groups, except Ble+Rem (P > 0.05), showed significant H₂O₂ penetration compared with control (P < 0.05). Color alteration analysis showed that ΔL and ΔE were significantly higher in the bleached groups than those in control (P < 0.05); the Δb of the bleached groups differed from that of control at 24 h (P < 0.05). At two days, necrosis or inflammation was observed in the bleached groups compared with control (P < 0.05), except Ble+Rem, which was similar to control (P > 0.05). At 30 days, tertiary dentin formation was significant in the bleached groups (P < 0.05), except Ble+Rem (P > 0.05).

CONCLUSION

The mixture of MI Paste Plus and bleaching gel reduces H₂O₂ penetration and pulp damage and maintains bleaching effectiveness.

CLINICAL RELEVANCE

Because bleaching can damage dental tissues, we studied a new bleaching protocol that reduces damage to the pulp tissue while maintaining bleaching efficiency: a single application of 30 min of MI Paste Plus mixed with 35% H₂O₂ bleaching gel (1:1).

Efficacy of diode and CO2 lasers along with calcium and fluoride-containing compounds for the remineralization of primary teeth

Background

This study aimed to assess the efficacy of a 980-nm diode and 10.6-μm CO₂ laser accompanied by tricalcium phosphate-5% sodium fluoride (fTCP) and casein phosphopeptide amorphous calcium phosphate (CPP-ACP) for the remineralization of primary teeth.

Methods

In total, 117 extracted primary anterior teeth were randomly divided into eight experimental and one control group: (I) control (polished enamel), (II) fTCP varnish, (III) fTCP + diode laser, (IV) fTCP + CO₂ laser, (V) CPP-ACP, (VI) CPP-ACP + diode laser, (VII) CPP-ACP + CO₂ laser, (VIII) diode laser, and (IX) CO₂ laser. The microhardness of 12 samples in each group and the enamel porosity of one sample in each group were assessed before and after demineralization and 28 days after remineralization. Data were analysed using two-way ANOVA.

Results

Significant differences existed in microhardness (P = 0.004) and percentage of remineralization (P < 0.001) after remineralization among the material groups such that the highest mean was noted in the CPP-ACP group. No significant difference was noted in microhardness (P = 0.052) or percentage of remineralization (P = 0.981) after remineralization among the laser groups. In all groups, porosities increased after demineralization and slightly decreased after remineralization; the greatest reduction in porosity of the material groups was noted in the fTCP group, and the CO₂ group among the laser groups. The interaction effect of materials and lasers was not significant (P > 0.05).

Conclusion

The highest microhardness was achieved after remineralization with CPP-ACP. The efficacy of the diode and CO₂ lasers was the same. No synergistic effect was found between materials and lasers.

Trial registration

This is not a human subject research.

The combined antimicrobial effect of arginine and fluoride toothpaste

The aim of the study was to investigate the antibacterial effect of arginine (Arg) in NaF toothpaste. 24-h mono-/3-species biofilm cultures of S. mutans, S. sanguis and S. gordonii inoculated sHA discs were subjected to treatment with toothpaste supernatants prepared as - [1]:2% Arg -NaF (0.147% F), [2]:4% Arg-NaF (0.144% F), [3]:8% Arg - NaF (0.138% F), [4]:NaF (0.15%) and [5]:deionized water. After 24-h incubation, the mono-species biofilms were subjected to viability assay using WST-8, SEM and confocal imaging (CLSM). The 3-species biofilm were quantified for bacterial composition by PCR analysis, SEM, CLSM, and RNA isolation with reverse-transcription PCR analysis. Increasing arginine concentrations in NaF toothpaste had no effect on microbial viability. The mono-/3-species biofilm imaging depicted that the 2% Arg-NaF and 4% Arg-NaF had a biofilm disrupting effect. The 3-species biofilm bacterial composition indicated that the 2% Arg-NaF group maintained an ecological homeostasis by inhibiting S. mutans growth and enriching the growth of S. sanguis and S. gordonii. The 2% Arg-NaF group significantly downregulated the expression of virulent gtfB gene and upregulated the expression of sagP with relative dominance of arcA. Incorporation of 2% arginine in NaF toothpaste might enrich the alkali-producing bacteria and provide enhanced counter mechanisms against cariogenic pathogen when compared to NaF toothpaste.

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.

Effects of fluoride versus amorphous calcium phosphate solutions on enamel microhardness of white spot lesions: An in-vitro study

Background

Development of white spot lesions around orthodontic fixed orthodontic appliances is a common finding, especially in patients with poor oral hygiene. One of the conservative interventions for regression of these lesions is using chemical solutions. The current study aimed to compare the effectiveness of fluoride and amorphous calcium phosphate (ACP) on microhardness improvement of affected enamel.

Material and Methods

Forty-five intact human incisor teeth were selected and randomly divided into 3 groups of 15. Fluoride group, ACP group and artificial saliva group (control group). Inducing of white spot lesion was done by PH-cycling model. Samples of the first and second group were submerged into 0.05% fluoride and 0.05% ACP solutions respectively for one minute a day. The rest of the time, all specimens were put in artificial saliva, which was incubated in 37 °c temperature. Microhardness of specimens was assessed by Vickers microhardness test in three stages: 1: Baseline microhardness assessment that was done before induction of white spot lesion, 2: Secondary microhardness assessment that was done after induction, 3: Final microhardness assessment that was done after chemical treatment. The SPSS 11.5 software was used for statistical analysis and p< 0.05 was considered as significant.

Results

Microhardness of specimens in the fluoride and ACP groups had significantly improved after the treatment (between secondary assessment and final assessment). In the control group, no significant improvements were observed. In final assessment, there were significant differences between the ACP and control groups, but no significant differences were found neither between the fluoride and ACP, nor the Fluoride and control groups.

Conclusions

According to the current study, both 0.05% ACP and 0.05% fluoride solutions enhanced enamel micro-hardness in treatment of white spot lesion.

Key words:Microhardness, amorphous calcium phosphate, fluoride, white spot lesion.

Enamel demineralization around metal and ceramic brackets: an in vitro study

Aim

To evaluate the degree of enamel demineralization of teeth bonded with ceramic and metal brackets.

Materials and methods

In this cross-sectional experimental in vitro study, 60 extracted human premolar teeth were selected according to the experimental criteria. They were divided into three groups; 20 premolar teeth in each group. Teeth in group 1 were bonded with "ceramic brackets", and teeth in group 2 were bonded with "metal brackets", while teeth in group 3 served as the "control group" without any brackets. Teeth in all groups were then immersed in demineralization media, de-bonded, sectioned into three parts (proximal 1, middle, and proximal 2), and evaluated to determine the level of enamel demineralization under a Scanning Electron Microscope.

Results

On tooth level, the results show that the control group has significantly less enamel demineralization compared to the other two experimental groups, with mean values of 145.3 µm and 192.7 µm, respectively (P=0.000). The mean value of enamel demineralization in the metal group is 55.93 µm, compared to 72.55 µm in the ceramic group, which is significantly less (P≤0.05), while there is no difference between the control and metal group with regard to enamel demineralization. On section level, the control group has significantly less enamel demineralization in all three sections compared to the ceramic group, while a significant difference is found in one of the proximal sections when compared with the metal group. Moreover, the ceramic group has significantly higher enamel demineralization in the middle section compared to the metal group (73.54 µm, 46.5 µm, respectively) (P=0.000), while there is no statistical significant difference between the two experimental groups in proximal sections.

Conclusion

In vitro, non-bonded teeth show least demineralization compared to the bonded teeth. Teeth bonded with ceramic brackets show significantly higher enamel demineralization compared to teeth bonded with metal brackets.

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.

Assessment of the Raman spectroscopy effectiveness in determining the early changes in human enamel caused by artificial caries

Raman maps indicate the changes in enamel affected by the early demineralization process with the use of new parameters.

Resin Infiltration of Artificial Enamel Lesions: Evaluation of Penetration Depth, Surface Roughness and Color Stability

Aim

To evaluate the penetration depth, surface roughness, and color stability of resin infiltration restoration of artificial enamel lesions induced in primary and permanent teeth.

Materials and methods

Primary (group I, n = 30) and permanent (group II, n = 30) extracted non-carious human anterior teeth were subjected to demineralization for four days after creating a window of 5 mm × 5 mm on the labial surfaces. Demineralized area was infiltrated with the low viscosity resin. Ten samples from each group were evaluated for penetration depth, surface roughness, and color stability, respectively. Penetration depth was determined using a stereomicroscope at 80× magnification. Surface roughness of sound and infiltrated enamel was recorded using a profilometer. The color stability was assessed at 2, 4, and 8 weeks along with baseline values using vita easy shade spectrophotometer.

Results

Data were analyzed using the student “t” test and Friedman test. The degree of resin penetration was observed to be higher in primary teeth (32.6 ± 15.72 μm) compared to permanent teeth (24.23 ± 6.85 μm), but no significant difference was found (p = 0.138). Surface roughness values of resin infiltrated enamel is similar to that of sound enamel in both primary (p = 0.617) and permanent teeth (p = 0.234). The mean color stability scores immediately after resin infiltration at 2, 4, and 8 weeks intervals showed no statistically significant difference in primary (p = 0.998) and permanent teeth (p = 0.213).

Conclusion

Resin penetration into enamel lesions was more in primary teeth enamel compared to permanent. The early enamel lesions, when treated with resin infiltration, showed surface characteristics similar to sound enamel and also exhibited acceptable color up to 8 weeks duration.

Clinical significance

Resin infiltration can be considered as an effective and predictable treatment option for the restoration of early enamel lesions owing to its deeper penetration, provision of better surface characteristics, and reliable masking of white spot lesions in both primary and permanent dentitions.

How to cite this article

Aswani R, Chandrappa V, Uloopi KS, et al. Resin Infiltration of Artificial Enamel Lesions: Evaluation of Penetration Depth, Surface Roughness and Color Stability. Int J Clin Pediatr Dent 2019;12(6):520–523.