Casein phosphopeptide-amorphous calcium phosphate: a remineralizing agent of enamel

Characteristics of casein phosphopeptides in Chinese human milk and its correlation with infant growth: A cross-sectional study

This research aimed to investigate the characteristics of casein phosphopeptides in Chinese human milk, and their potential relationship to infant growth. Using the liquid chromatography-Orbitrap-mass spectrometry technique, a total of 15 casein phosphopeptides were identified from 200 human milk samples. Also, our results indicate that casein phosphopeptides were phosphorylated with only one phosphate. The relative concentrations of casein phosphopeptides at 6 months postpartum were increased compared with milk at 2 months (FDR < 0.05). Significantly positive correlations were observed between casein phosphopeptides and infant growth, as shown by four casein phosphopeptides were positively correlated with the infants' weight-for-age Z-scores (rs range from 0.20 to 0.29), and three casein phosphopeptides were positively correlated with the infants' length-for-age Z-scores (rs range from 0.19 to 0.27). This study is the first to reveal the phosphorylated level and composition of casein phosphopeptides in Chinese human milk, and their potential relationship with infant growth.

Anti-bacterial and anti-biofilm activities of arachidonic acid against the cariogenic bacterium Streptococcus mutans

Streptococcus mutans is a Gram-positive, facultative anaerobic bacterium, which causes dental caries after forming biofilms on the tooth surface while producing organic acids that demineralize enamel and dentin. We observed that the polyunsaturated arachidonic acid (AA) (ω-6; 20:4) had an anti-bacterial activity against S. mutans, which prompted us to investigate its mechanism of action. The minimum inhibitory concentration (MIC) of AA on S. mutans was 25 μg/ml in the presence of 5% CO2, while it was reduced to 6.25-12.5 μg/ml in the absence of CO2 supplementation. The anti-bacterial action was due to a combination of bactericidal and bacteriostatic effects. The minimum biofilm inhibitory concentration (MBIC) was the same as the MIC, suggesting that part of the anti-biofilm effect was due to the anti-bacterial activity. Gene expression studies showed decreased expression of biofilm-related genes, suggesting that AA also has a specific anti-biofilm effect. Flow cytometric analyses using potentiometric DiOC2(3) dye, fluorescent efflux pump substrates, and live/dead SYTO 9/propidium iodide staining showed that AA leads to immediate membrane hyperpolarization, altered membrane transport and efflux pump activities, and increased membrane permeability with subsequent membrane perforation. High-resolution scanning electron microscopy (HR-SEM) showed remnants of burst bacteria. Furthermore, flow cytometric analysis using the redox probe 2',7'-dichlorofluorescein diacetate (DCFHDA) showed that AA acts as an antioxidant in a dose-dependent manner. α-Tocopherol, an antioxidant that terminates the radical chain, counteracted the anti-bacterial activity of AA, suggesting that oxidation of AA in bacteria leads to the production of cytotoxic radicals that contribute to bacterial growth arrest and death. Importantly, AA was not toxic to normal Vero epithelial cells even at 100 μg/ml, and it did not cause hemolysis of erythrocytes. In conclusion, our study shows that AA is a potentially safe drug that can be used to reduce the bacterial burden of cariogenic S. mutans.

Effects of a 445 nm diode laser and silver diamine fluoride in preventing enamel demineralisation and inhibiting cariogenic bacteria

OBJECTIVE

To study the effects of a 445 nm diode laser (L) and silver diamine fluoride (F) on preventing enamel demineralisation and inhibiting cariogenic bacteria.

METHODS

Thirty-three enamel slices were sectioned each into four blocks for four groups to receive L with F (LF), F, L and Water (W, control). Ten blocks from each group were used to evaluate demineralization. Surface morphology, lesion depth and nanohardness of the blocks after pH-cycling were studied by scanning electron microscopy (SEM), nanohardness test, and micro-computed tomography, respectively. Twenty-three blocks per group were used for biofilm assessment. Morphology, viability, and growth kinetics of the Streptococcus mutans biofilm were assessed by SEM, confocal laser scanning microscopy, and the counting of colony-forming units (CFUs), respectively.

RESULTS

SEM images of LF-treated enamel showed an intact surface compared with other groups. Nanohardness (GPa) for LF, F, L and W were 1.43±0.17, 1.01±0.11, 1.04±0.13 and 0.73±0.14, respectively (p<0.001; LF>F, L>W). Their lesion depths (µm) were 46±8, 52±6, 88±13 and 111±9, respectively (p<0.001; LF, F<L<W). SEM showed few bacteria for LF and F compared with other groups. Their dead-live ratio were 1.67±0.13, 1.60±0.15, 0.39±0.05 and 0.32±0.05, respectively (p<0.001; LF, F>L>W). Log CFUs for LF, F, L and W were 4.2±0.3, 4.5±0.2, 7.9±0.3 and 9.4±0.2, respectively (p<0.05; LF<F<L<W). Two-way ANOVA analysis revealed an interaction effect on nanohardness and Log CFUs between the laser irradiation and SDF treatment (p<0.001).

CONCLUSION

This study showed a superior caries preventive effect of a combined treatment of the diode laser and SDF. Because diode laser and SDF are affordable and readily available, clinicians can provide this treatment to their patients for caries prevention.

CLINICAL SIGNIFICANCE STATEMENT

Diode lasers are handy, afforable and readily avaliable to clinicians. This study provides information of use of 445 nm diode laser for caries prevetion. The laser irradiation hopefully can be added before conventional topical SDF application.

Dental tissue remineralization by bioactive calcium phosphate nanoparticles formulations

Recent health care products are based on formulations claimed to provide enamel remineralization and dentinal tubules occlusion through calcium-phosphate bioactive nanocompounds (ion-doped hydroxyapatite and precursor, amorphous calcium phosphate nanoparticles). This study aimed to characterize, test, and compare for the first time the structure and performance of a representative, market-available sample of remineralizing toothpastes and topical mousses. Formulations were characterized to determine their composition and investigate the presence of bioactive compounds and doping elements. A conventional fluoride-containing toothpaste was used as reference. The enamel remineralization and efficacy of dentinal tubules occlusion by tested formulations were investigated ex vivo on human hard tissues. All formulations containing Ca-P bioactive nanocompounds showed remineralizing ability by epitaxial growth of a layer showing the morphology and composition of human hydroxyapatite. Such layers also embedded nanosilica clusters. The presence of doping elements or casein phosphopeptide seemed essential to allow such performances, especially when hydroxyapatite and amorphous calcium phosphate compounds were doped with small amounts of CO₃²⁻, F⁻, Mg²⁺, and Sr²⁺. Topical mousse formulations showed a higher tubules occlusion capability than toothpastes, independently from their composition. Therefore, all tested formulations could be useful in restoring tooth structures in a biomimetic way, contrasting dental demineralization processes leading to caries.

Effectiveness of Self-Assembling Peptide (P11-4) in Dental Hard Tissue Conditions: A Comprehensive Review

The limitations on the use of fluoride therapy in dental caries prevention has necessitated the development of newer preventive agents. This review focusses on the recent and significant studies on P11-4 peptide with an emphasis on different applications in dental hard tissue conditions. The self-assembling peptide P11-4 diffuses into the subsurface lesion assembles into aggregates throughout the lesion, supporting the nucleation of de novo hydroxyapatite nanocrystals, resulting in increased mineral density. P11-4 treated teeth shows more remarkable changes in the lesion area between the first and second weeks. The biomimetic remineralisation facilitated in conjunction with fluoride application is an effective and non-invasive treatment for early carious lesions. Despite, some studies have reported that the P11-4 group had the least amount of remineralised enamel microhardness and a significantly lower mean calcium/phosphate weight percentage ratio than the others. In addition, when compared to a low-viscosity resin, self-assembling peptides could neither inhibit nor mask the lesions significantly. Moreover, when it is combined with other agents, better results can be achieved, allowing more effective biomimetic remineralisation. Other applications discussed include treatment of dental erosion, tooth whitening and dentinal caries. However, the evidence on its true clinical potential in varied dental diseases still remains under-explored, which calls for future cohort studies on its in vivo efficacy.

Bioactive peptides from foods: production, function, and application

Bioactive peptides are a class of peptides with special physiological functions and have potential applications in human health and disease prevention. Bioactive peptides have gained much research attention because they affect the cardiovascular, endocrine, immune, and nervous systems. Recent research has reported that bioactive peptides are of great value for physiological function regulation, including antioxidation, anti-hypertension, antithrombosis, antibacterial properties, anti-cancer, anti-inflammation, anti-diabetic, anti-obesity, cholesterol-lowering, immunoregulation, mineral binding and opioid activities. The production of food-derived bioactive peptides is mainly through the hydrolysis of digestive enzymes and proteolytic enzymes or microbial fermentation. The purpose of this review is to introduce the production, function, application, challenges, and prospects of food-derived bioactive peptides.

Effect of Chlorhexidine Varnish and Fluoride Varnish on White Spot Lesions in Orthodontic Patients- a Systematic Review

Aim:

The aim of this study is to critically review the studies that studied the effect of Chlorhexidine varnish and fluoride varnish on White Spot Lesion (WSL) in patients undergoing orthodontic treatment.

Materials and Methods:

The electronic database PubMed, The Cochrane Library, Medline, Embase, Google Scholar, Web of Knowledge along with a complimentary manual search of all orthodontic journals till the first week of December 2019 was searched. English language study performed on humans, randomized or nonrandomized clinical trials, comparing the effect of fluoride and chlorhexidine varnish on WSL was included in the review. Quality assessment of included studies was performed.

Clinical Significance:

The need for an adjunct oral hygiene aid to reduce the incidence and prevalence of white spot lesions in orthodontic patients is necessary. The use of these varnishes will aid in the same and thus make the adverse effects of fixed orthodontic treatment negligible.

Review of Literature:

Enamel demineralization is a significant risk associated with orthodontic treatment when oral hygiene is poor. Prevention of demineralization during orthodontic treatment is one of the greatest challenges faced by clinicians despite modern advances in caries prevention. The development of White Spot Lesions (WSLs) is attributed to prolonged plaque accumulation around the brackets.

Results:

The search identified a total of 3 studies that were included in this review. One study had Low risk of bias and the remaining 2 studies had moderate overall risk. Results showed that there was a reduction in the incidence of white spot lesions in orthodontic patients after application of chlorhexidine and Fluoride varnish.

Conclusion:

Low level evidence is available to conclude that the use of chlorhexidine varnishes and fluoride varnishes reduces the prevalence of white spot lesions in patients undergoing fixed orthodontic treatment. Due to its limitations, the results of this systematic review should be handled with caution and further well-planned Randomized Clinical Trial (RCT) are needed to provide a discrete conclusion.

Size controlled fabrication of enzyme encapsulated amorphous calcium phosphate nanoparticle and its intracellular biosensing application

Inorganic-enzyme composites have been widely used for applications in catalysis and analytical science. Amorphous calcium phosphate, as a biocompatible material, can form open hydrated structure to encapsulate and protect enzymes. So far, there have been few progress on size-adjustable amorphous calcium phosphate nanoparticles since the diameter controllability is limited by its natural aggregation characteristics. By co-precipitation and nano-channel extrusion, we developed enzyme-loaded amorphous calcium phosphate nanoparticles with adjustable diameters. These enzyme-loaded particles showed high thermal and chemical stability as well as biocompatibility. The nano-sized enzyme-loaded particles can further expand their application fields and be used as intracellular enzyme probes. Delivering glucose oxidase enzyme by amorphous calcium phosphate nanoparticles enables fluorescent monitoring of glucose levels in living cells, which can be used to study the metabolism rates of cancer cells and normal cells. The nano-channel extrusion method can also be used as a template to encapsulate different kinds of enzymes to expand catalysis and biosensing applications.

Effect of Prior Application of Desensitizing Agent on the Teeth Submitted to In-Office Bleaching

This study aimed to quantify the penetration of hydrogen peroxide, color change evaluation, surface morphology, and composition after application of desensitizing agents before in-office bleaching. Fifty premolars were sectioned, an acetate buffer was placed in the pulp chamber and divided into five groups (n=10). In the positive control group, only the in-office bleaching gel was used, and in the negative control group, no treatment was used. Three different desensitizing agents were applied: Desensibilize KF2%® group; Mi Paste® group, and Desensibilize Nano-P® group. The bleaching procedure was carried out with 35% HP. The absorbance of the resulting solution was determined in a spectrophotometer. Color change was assessed by using a digital spectrophotometer. Four additional premolars were assigned to the same groups above for analysis under scanning electron microscope, as well as to evaluate the elemental composition with X-ray dispersive energy spectrometry. Data were subjected to ANOVA and Tukey's test (α=0.05). All products reduced the penetration of HP in the pulp chamber. Mi Paste and Nano P were the products that yielded the lowest HP penetration, which was similar to the negative control group (p<0.001). No significant difference was detected in color change (p<0.001). Concerning enamel morphology, the groups that were analyzed after bleaching were observed a greater deposition of desensitizing agents on the surface. The use of desensitizing agents before tooth bleaching seems to be an alternative to reduce adverse effects of the tooth.

The Protein Level and Molecular Weight Analysis in Different Children's Toothpaste, which Probably Induced Hypersensitivity

CONTEXT

A new case of an allergic reaction due to the use of toothpaste was found in California, United States, causing the death of an 11-year-old girl. Ingredients contained in toothpaste suspected as a cause of allergies are milk protein compounds.

AIMS

The aim is to compare the protein level and molecular weight in children's toothpaste.

SETTINGS AND DESIGN

Stratified random sampling.

SUBJECTS AND METHODS

Samples used were children's toothpaste products in society, namely, Pepsodent®, Cussons®, Enzyme®, Kodomo®, Formula®, Colgate®, the toothpaste contain recaldent of GC Tooth Moose® and pure cow's milk. Those samples were divided into eight groups, randomly selected according to the purpose (stratified random sampling), and then coded to maintain product confidentiality. Meanwhile, samples used as comparison groups were recaldent paste and pure cow's milk.

RESULTS

Each sample was analyzed for protein content using a biuret test and protein molecular weight using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis test. The protein content in toothpaste is compared with the similarity of the molecular protein weight in toothpaste that contains recaldent. Protein was found in samples 2, 3, 5, 6, 7, and 8 through a biuret test, with a concentration of 1.82; 1.53; 2.76; 1.92; 1.85; and 3.2 μg/mL. However, the protein bands were only found in sample 5 with a molecular weight of 20.7 kDa, sample 6 with a molecular weight of 19.1 kDa, sample 7 with a molecular weight of 17.7 kDa, and sample 8 with 2 bands, namely, 28.7 and 39.7 kDa.

CONCLUSIONS

We found the presence of protein in children's toothpaste. The protein molecular weight of recaldent paste is 17.7 kDa. Toothpaste containing protein with its molecular weight similar to recaldent's are found in samples 5 and 6.

Effective Preparation Method of Phosphopeptides from Phosvitin and the Analysis of Peptide Profiles Using Tandem Mass Spectrometry

The effect of high-temperature and mild-pressure (HTMP) pretreatment on the enzymatic hydrolysis of phosvitin and the structural characteristics of the phosphopeptides produced were analyzed using tandem mass spectrometry. The HTMP pretreatment hydrolyzed phosvitin at random sites and helped the subsequent enzyme hydrolysis of the peptides produced. With the HTMP pretreatment alone, 154 peptides were produced, while the use of trypsin, Protex 6L, and Multifect 14L in combination with the pretreatment produced 252, 280, and 164 peptides, respectively. The use of two enzyme combinations (trypsin + Protex 6L and trypsin + Multifect 14L) helped the hydrolysis further. The number of phosphopeptides produced increased when the modifications within the same amino acid sequences were considered. This study indicated that HTMP pretreatment was a breakthrough method to improve the enzymatic hydrolysis of phosvitin that enabled an easy production of phosvitin phosphopeptides for their subsequent functional characterizations.

The importance of being amorphous: calcium and magnesium phosphates in the human body

This article focuses on the relevance of amorphous calcium (and magnesium) phosphates in living organisms. Although crystalline calcium phosphate (CaP)-based materials are known to constitute the major inorganic constituents of human hard tissues, amorphous CaP-based structures, often in combination with magnesium, are frequently employed by Nature to build up components of our body and guarantee their proper functioning. After a brief description of amorphous calcium phosphate (ACP) formation mechanism and structure, this paper is focused on the stabilization strategies that can be used to enhance the lifetime of the poorly stable amorphous phase. The various locations of our body in which ACP (pure or in combination with Mg²⁺) can be found (i.e. bone, enamel, small intestine, calciprotein particles and casein micelles) are highlighted, showing how the amorphous nature of ACP is often of paramount importance for the achievement of a specific physiological function. The last section is devoted to ACP-based biomaterials, focusing on how these materials differ from their crystalline counterparts in terms of biological response.

Monitoring demineralization and remineralization of human dentin by characterization of its structure with resonance-enhanced AFM-IR chemical mapping, nanoindentation, and SEM

OBJECTIVE

This research aimed at monitoring demineralization and remineralization of dentin and its collagen matrix at the nanoscale by amorphous, microcrystalline, and in situ formed hydroxyapatite.

METHODS

The concurrent use of the resonance-enhanced atomic force microscopy coupled with infrared probe (AFM-IR) chemical mapping, nano-indentation, and scanning electron microscopy (SEM) provides a detailed insight into the structure of human dentin, as well as to the processes of its partial demineralization and remineralization.

RESULTS

The resonance-enhanced AFM-IR chemical mapping of dentin has shown to be a useful method to follow distribution of its collagen and hydroxyapatite components at the micro- and nanoscale levels, especially in conjunction with SEM imaging and nanoindentation. Dentin with a higher extent of natural dentin tubule occlusion tends to be harder and less elastic. The relative affinity of the collagen and hydroxyapatite components of dentin toward hydroxyapatite depends on its type (amorphous, microcrystalline, or formed in-situ). The gel mineralization technique allows for an even and controlled growth of hydroxyapatite guided by the completely demineralized collagen matrix of dentin.

SIGNIFICANCE

The observed trends of the affinity of collagen toward different forms of hydroxyapatite helps develop new remineralizing formulations. The employed methods of characterization may provide an insight to the natural processes of bone mineralization guided by its both hydroxyapatite and protein constituents.

How Can the Value and Use of Egg Yolk Be Increased?

The major driving force for the egg consumption in the United States over the past few decades was processed egg. However, the consumption of egg through the processed egg reached the plateau in recent years because of the imbalance in the demands between the egg white and yolk products. The consumer demands for egg white products are very high while those for the egg yolk, the co-product of dried egg white, are low because of the negative perceptions on egg yolk. Two key approaches that can be used to increase the value and use of egg yolk are: (1) developing new commodity products by fractionating egg yolk and apply them in various food processing, and (2) separating functional proteins and lipids from yolk and use them as is or further develop functional peptides and functional lipids and use them as pharmaceutical, nutraceutical, and cosmeceutical agents. These approaches can diversify the use of egg yolk, which eventually will help increase the consumption of egg. This review (1) discusses the current use of egg yolk products and the development of new functional commodity products from egg yolk, (2) review the important functional components in egg yolk and overview the current separation methods and their applications, (3) discuss the production of functional peptides and lipids using the separated egg proteins and lipids, and (4) suggest the future directions for the best use of egg yolk components. Development of scale-up production methods, which is vital for the practical applications, is discussed when appropriate.

Dietary bioactive peptides: Human studies

Current opinion strongly links nutrition and health. Among nutrients, proteins, and peptides which are encrypted in their sequences and released during digestion could play a key role in improving health. These peptides have been claimed to be active on a wide spectrum of biological functions or diseases, including blood pressure and metabolic risk factors (coagulation, obesity, lipoprotein metabolism, and peroxidation), gut and neurological functions, immunity, cancer, dental health, and mineral metabolism. A majority of studies involved dairy peptides, but the properties of vegetal, animal, and sea products were also assessed. However, these allegations are mainly based on in vitro and experimental studies which are seldom confirmed in humans. This review focused on molecules which were tested in humans, and on the mechanisms explaining discrepancies between experimental and human studies.

Effect of Green and White Tea Pretreatment on Remineralization of Demineralized Dentin by CPP-ACFP-An Invitro Microhardness Analysis

INTRODUCTION

Mechanical performance of dentine is of major significance for the overall function of the teeth. Remineralization of carious dentine is the ultimate goal in re-establishing the functionality of the affected tissue so as to regain and maintain the mechanical properties of dentine. Functional remineralization of the affected dentin involves stabilization of both inorganic and organic component, but Caesin Phosphopeptide Amorphous Calcium Flurophosphate (CPP-ACFP) stabilizes only inorganic content. Hence to stabilize organic content and to bring in functional remineralization the use of anticollagenolytic and antielastastic agent was considered for this study.

AIM

To assess and compare the remineralization of artificial carious dentin pre treated with white and green tea, before and after application of CPP-ACFP using microhardness test. Null hypothesis was that both teas did not have any effect on remineralization potential of CPP ACFP.

MATERIALS AND METHODS

Forty specimens were subjected to artificial caries lesions and were randomly divided into 4 groups based on the application of tea extract followed by CPP-ACFP (groups A & B) and CPP-ACFP followed by tea extracts (groups C & D). All the specimens were subjected to two pH cycling regimen. The specimens were subjected to Vickers microhardness test to obtain the microhardness values. The values were statistically analysed using one-way ANOVA and multiple comparisons with Tukey's HSD procedure.

RESULTS

After the 1(st) and 2(nd) pH cycling in groups A and B, Group B showed significant increase in microhardness values (35.79± 3.12 VHN). But after the pH cycling regimen in groups C and D, microhardness values increased in 1(st) pH cycling (50.03± 3.64 VHN); (50.03±3.64 VHN), respectively but decreased during the 2(nd) pH cycling, (33.94±6.45 VHN); (33.11±6.11 VHN) respectively with the level of significance <0.05.

CONCLUSION

The results of this study rejects the hypothesis tested and showed that both the tea extracts increased the microharness values when used prior to the application of remineralizing agent. However, 10% white tea showed better microhardness indicating stabilization of collagen in dentine resulting in functional remineralization.

Prevention of enamel demineralization with a novel fluoride strip: enamel surface composition and depth profile

There is no topically applicable low concentration fluoride delivery device available for caries prevention. This study was aimed to assess the use of a low concentration (1450 ppm) fluoride strip as an effective fluoride delivery system against enamel demineralization. The enamel surface composition and calcium-deficient hydroxyapatite or toothpaste treatments were investigated using X-ray photoelectron spectroscopy. In vitro enamel demineralization was assayed using a pH cycling model and the dissolution of calcium ions from the treated specimens was quantified using ion chromatography. After 24-hr fluoride-strip treatment, the enamel was covered with a CaF₂ layer which showed a granular morphology of 1 μm in size. Below the CaF₂ layer was a region of mixed fluorapatite and CaF₂. Fluoride infiltrated extensively in enamel to produce highly fluorinated fluorohydroxyapatite. In comparison, low-fluoride-level fluorinated fluorohydroxyapatite was formed on the enamel specimen exposed to toothpaste. The treatments with the fluoride strip as short as 1 hr significantly inhibited enamel demineralization. The fluoride strip was effective for topical fluoride delivery and inhibited in vitro demineralization of enamel by forming CaF₂ and fluoride-containing apatites at the enamel surface. It exhibited the potential as an effective fluoride delivery device for general use in prevention of caries.

Amorphous calcium phosphate nanowires prepared using beta-glycerophosphate disodium salt as an organic phosphate source by a microwave-assisted hydrothermal method and adsorption of heavy metals in water treatment

Amorphous calcium phosphate nanowires were prepared using β-glycerophosphate disodium salt as the phosphate source by a microwave-assisted hydrothermal method.

In situ effect of a commercial CPP-ACP chewing gum on the human enamel initial erosion

OBJECTIVE

This study evaluated the in situ rehardening effect of a commercial chewing gum containing casein phosphopeptide - amorphous calcium phosphate (CPP-ACP) on initial erosion lesions.

METHODS

Seventy-two human enamel blocks, after selection (initial surface hardness - SHi) and in vitro short-term acidic exposure (cola drink for 3 min - SHd) were randomly assigned to three groups. The factors under study were treatment (3 levels: GI chewing gum with CPP-ACP, GII chewing gum without CPP-ACP and GIII control group without gum) and intraoral period (2 levels: 2 and 24h). Twelve volunteers wore intraoral palatal devices for 24h in 3 crossover phases. On each phase, after 2h the surface hardness was assessed (SHf1) and the blocks were reinserted and the devices were used for additional 22 h (SHf2). In phases of GI and GII volunteers chewed the respective gum during 30 min, for 4 times with an interval of 4h. Percentage of surface hardness recovery (%SHR) was calculated after 2 and 24 h. The data were analysed by repeated measures ANOVA and Tukey's test.

RESULTS

Chewing gum with CPP-ACP (2h=50.0%<24h=95.9%) showed higher hardness recovery than chewing gum without CPP-ACP (2h=30.0%<24 h=71.1%) and control (2 h=15.7%<24 h=40.9%) (p<0.05).

CONCLUSIONS

The results suggest that saliva increased hardness of softened enamel after the use of conventional chewing gum (GII) and this effect was enhanced by the prolonged intraoral period (24 h) and by the use of CPP-ACP chewing gum (GI).

CLINICAL SIGNIFICANCE

Since chewing gum is an alternative to enhance salivary defenses after erosive challenges, CPP-ACP chewing gum might be a supplementary strategy to potentiate the mineral precipitation of initial erosion lesions.