UNIVERSIDADE ESTADUAL PAULISTA

“JÚLIO DE MESQUITA FILHO”

Instituto de Ciência e Tecnologia

Campus de São José dos Campos

ORIGINAL ARTICLE DOI: https://doi.org/10.4322/bds.2024.e4246

Braz Dent Sci 2024 Apr/June;27 (2): e4246

This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in

any medium, provided the original work is properly cited.

Remineralizing potential of a ﬂuoride varnish modiﬁed by bioactive

nanoparticles

Potencial remineralizante de um verniz ﬂuoretado modiﬁcado por nanopartículas bioativas

Alyssa Teixeira OBEID1 , Marilia Mattar de Amoêdo Campos VELO1 , Tatiana Rita de Lima NASCIMENTO2 ,

Denner Leopoldino ESPERANÇA1 , Laís Santos ALBERGARIA1 , Juliana Fraga Soares BOMBONATTI1 

1 - Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Dentística, Endodontia e Materiais Odontológicos,

Bauru, SP, Brazil.

2 - Universidade Federal da Paraíba, Centro de Pesquisa em Combustíveis e Materiais, Departamento de Química, João Pessoa, PB, Brazil.

How to cite: Obeid AT, Velo MMAC, Nascimento TRL, Esperança DL, Albergaria LS, Bombonatti, JFS. Remineralizing potential of a uoride

varnish modied by bioactive nanoparticles. Braz Dent Sci. 2024;27(2):e4246. https://doi.org/10.4322/bds.2024.e4246

ABSTRACT

Objective: Evaluate a uoride varnish modied by nanostructures with the bioactive qualities of silica (SiO2)

and niobium pentoxide (Nb2O5), testing its remineralizing potential by surface hardness (SH) and energy-

dispersive X-ray spectroscopy (EDX). Material and Methods: Bovine enamel specimens (6×4×2mm) were

prepared and submitted to a demineralizing/remineralizing process to produce a subsurface caries-like lesion,

evaluated by transversal microradiography image (TMR) and subsequently distributed randomly into three groups:

uoride varnish (VZ); uoride varnish + silica gelatin (VZ-SiO2) and uoride varnish + niobium nanoparticles

(VZ-Nb2O5). The specimens were subjected to a pH-cycling demineralizing/remineralizing process for 7 days

at 37ºC. The %SH loss and %SH recovery (after the pH-cycling regimen) were calculated (n=10/group). The

Ca/P weight ratio before and after the pH-cycling regimen was evaluated through SEM/EDX. A two-way ANOVA

followed by Tukey’s test (p<0.05) was performed for hardness and EDX. Results: TMR image showed the

formation of an articial subsurface lesion, and a signicant SH increase was observed in the VZ-Nb2O5 group

(p<0.05). Regarding the %SHL and %SHR, the VZ-Nb2O5 and VZ-SiO2 were signicantly different compared

to the VZ group (p<0.001), but VZ-Nb2O5 presented higher values. The Ca/P ratio showed that blocks treated

with VZ-SiO2 and VZ-Nb2O5 showed greater ion deposition, particularly in the presence of Nb. Conclusion:

The bioactivity of niobium facilitated greater interaction between the enamel and the varnish, leading to a slow

release of nanoparticles and a longer-lasting remineralizing effect.

Keywords

Fluorides; Nanostructures; Niobium; Operative dentistry; Tooth remineralization.

RESUMO

Objetivo: Avaliar um verniz uoretado modicado por nanoestruturas com a bioatividade da sílica (SiO2) e

pentóxido de nióbio (Nb2O5), testando seu potencial remineralizador pela dureza de superfície (SH) e espectroscopia

de energia dispersiva de raios-X (EDX). Material e Métodos: Espécimes de esmalte bovino (6×4×2mm) foram

preparados e submetidos à desmineralização/remineralização para produzir uma lesão subsupercial semelhante

a cárie, avaliada por imagem de microrradiograa transversal (TMR) sendo distribuída em três grupos: verniz

uoretado (VZ); verniz uoretado+gelatina de sílica (VZ-SiO2) e verniz uoretado+nanopartículas de nióbio

(VZ-Nb2O5). As amostras foram submetidas à desmineralização/remineralização por ciclagem de pH durante 7

dias a 37°C. A porcentagem de perda e recuperação de SH foram calculadas (n=10/grupo). A relação em peso

Ca/P antes e depois da ciclagem foi avaliada através de MEV/EDX. ANOVA a dois critérios seguida do teste

de Tukey (p<0,05) foi realizada para dureza e EDX. Resultados: A TMR mostrou a formação de uma lesão

subsupercial e um aumento signicativo de SH foi observado no grupo VZ-Nb2O5 (p<0,05). Em relação ao

%SHL e %SHR, o VZ-Nb2O5 e o VZ-SiO2 foram signicativamente diferentes em relação ao grupo VZ (p<0,001),

Braz Dent Sci 2024 Apr/June;27 (2): e4246

Obeid AT et al.

Remineralizing potential of a fluoride v arnish modified by bioactiv e nanoparticles

Obeid AT et al. Remineralizing potential of a ﬂuoride varnish modiﬁed by

bioactive nanoparticles

INTRODUCTION

In recent years, there has been a shift in dental

approaches towards preventive methods, risk

control, and early diagnosis of tooth decay, moving

away from extensive restorative procedures [1].

One of the key focuses is on remineralizing subsurface

carious lesions before they progress to cavitation,

thus avoiding the need for invasive restorative

interventions [2-4]. The prevention, diagnosis, and

early treatment of active white spot lesions through

remineralizing products are crucial in preventing

the need for more invasive treatments [5]. These

agents can recover the mineral loss, and they

are regarded as a very helpful alternative and a

preventive step to control the demineralization

process instead of invasive techniques [6]. White

spot lesions (WSL) are identied with the loss of

minerals, despite the hard dental surfaces. Most of

the situations are associated with poor oral hygiene,

hypofunction of salivary glands, and early WSL

having a reversible hard surface [7].

Fluoride varnish is a noninvasive treatment

option in the remineralization process. It is

safe, effective, and can enhance the results of

topical uoride therapies by increasing enamel

exposure to fluoride. Sodium fluoride (NaF)

varnish is one derivative that is topically applied.

The concentration of uoride and the duration

of contact between fluoride and the tooth

structure determine the extent to which the tooth

structure absorbs uoride. Multiple application

sessions are typically required annually [8],

requiring patient cooperation [9]. Fluoride

varnish aids in remineralization by releasing

calcium, phosphate, and uoride ions, thereby

increasing the saturation level in the liquid

medium surrounding dental hard tissues. This

promotes the remineralization process [10].

Fluoride has also been shown to signicantly

reduce bacterial adhesion to tooth surfaces [11]

and increase enamel surface hardness [12].

Different remineralizing agents are constantly

being evaluated to achieve a more consistent and

stable effect on enamel remineralization. The use

of silica (SiO2) in the remineralization of enamel

caries lesions has shown promising results and more

effective in enamel remineralization compared to

other topical agents such as uoride and Casein

Phosphopeptide - Amorphous Calcium Phosphate

(CPP-ACP) [13]. It has been demonstrated that

incorporating tailored hybrid nanobers doped

with SiO2 and SiO2-CaP into enamel resin inltrants

can inhibit demineralization and increase enamel

hardness [14].

Nanoparticles containing SiO2 derived from

the sol-gel process have shown increased apatite

deposition [15], demonstrating bioactivity

potential. When in contact with saliva, sodium ions

from silica particles react with hydrogen cations

from saliva, leading to the release of calcium and

phosphate ions. The increase in salivary pH helps

to precipitate the extra calcium and phosphate

ions, resulting in the formation of calcium uoride

and eventually hydroxyapatite. This enhances the

remineralization of tooth structures [13,16].

However, one challenge with bioactive materials

is their low mechanical strength [17]. With

advancements in nanotechnology, bioactive

materials with improved mechanical properties

have been investigated for dentistry and

biomedical applications [14,18-20].

One example is niobium pentoxide (Nb2O5),

a metallic oxide that exhibits bioactivity, develops

hydroxyapatite crystals when in contact with

human saliva and offers excellent mechanical

properties [18]. It was demonstrated that the

incorporation of nanobers doped by Nb2O5 in one

self-adhesive resin cement promotes signicant

improvements in the mechanical properties of

the material [21]. In addition, Nb2O5 has optical

properties similar to tooth structure, being

interesting for dental materials applications [22].

Therefore, modifying a fluoride varnish

with bioactive glass particles could enhance the

deposition of calcium and phosphate ions, thus

improving its cariostatic effect. Additionally, the

mas o VZ-Nb2O5 apresentou valores maiores. A relação Ca/P mostrou que os blocos tratados com VZ-SiO2 e

VZ-Nb2O5 apresentaram maior deposição de íons, principalmente na presença de Nb. Conclusão: A bioatividade

do nióbio facilitou maior interação entre o esmalte e o verniz, levando a uma liberação lenta de nanopartículas

e a um efeito remineralizante mais duradouro.

PALAVRAS-CHAVE

Fluoretos; Nanoestruturas; Nióbio; Dentística operatória; Remineralização dentária.

Braz Dent Sci 2024 Apr/June;27 (2): e4246

Obeid AT et al.

Remineralizing potential of a fluoride v arnish modified by bioactiv e nanoparticles

Obeid AT et al. Remineralizing potential of a ﬂuoride varnish modiﬁed by

bioactive nanoparticles

incorporation of Nb2O5 particles could increase

the varnish’s resistance to cariogenic challenges

and prolong its effectiveness, reducing the need

for frequent reapplications. The objective of this

study was to evaluate the remineralizing potential

of a varnish modied with bioactive nanomaterials

(Nb2O5 and SiO2) through surface hardness and

energy-dispersive X-ray spectroscopy (EDX)

analyses. The null hypothesis tested was that

the experimental materials would not possess

remineralizing potential and bioactivity.

MATERIAL AND METHODS

Sample preparation

Sixty-five extracted non-carious bovine

mandibular incisors were obtained under a

protocol registered and approved by the Animal

Use Ethics Committee (#004/2020). The teeth

were selected using 10 × magnifying glass

support, excluding those with cracks, caries

and/or fractures. The roots of each tooth were

sectioned 1 mm below the enamel-cementum

junction using an IsoMet low-speed saw (Buehler;

Lake Bluff, IL, USA) equipped with a diamond

disc (Extec; Eneld, CT, USA). Subsequently,

enamel slabs were prepared (6×4×2mm3) at

a speed of 300 rpm under continuous water

irrigation. The specimens were then polished at

using abrasive papers (#600-grit to #1200-grit)

followed by a felt disk with a diamond suspension

(Buehler; Lake Bluff, IL, USA), in a polishing

machine (Politriz APL-4 AROTEC, Cotia, SP,

Brazil).

The baseline SH of the dental slabs was

determined by three indentations (n = 10) in

specimens, using a Knoop diamond indenter

with intervals of 100 μm from each other.

Assessments were made with a 50-g load for 10 s

(MicroMet 6040; South Bay Technology, Lake

Bluff, IL, USA). Before submitting the specimens

to any further process for the production of a

simulated caries-like lesion, blocks were divided

into three areas of 2×4×2mm3 (control, only

demineralized and treated) by acid-resistant

varnish. The demineralizing solution was

developed with the composition: 1.3 mM

Ca(NO3)2.4H20; 0.78 mM Na2HPO4.2H20; 0.05 M

glacial acetic acid; 0.0315 ppm F; pH 5.0 at

37°C [23]. The selected specimens remained for

16 hours in this solution (30 ml per specimen).

The SH of the dental slabs was again determined

after caries-like induction by three indentations

in specimens and submitted to Transverse

microradiography.

Transverse microradiography (TMR)

The specimens were longitudinally sectioned

at the center of the carious surface using an

IsoMet low-speed saw (Buehler; Lake Bluff, IL,

USA) and a double-sided diamond disc – XL

12205, cooled with purified water. This step

enabled the acquisition of a fragment with a

thickness of approximately 500 μm to prevent

dentin fracture. To achieve a thickness suitable

for analysis (120–130 μm), the fragments were

manually polished using abrasive papers #600-

grit to #1200-grit moistened with puried water.

The nal thickness was conrmed using a digital

micrometer (Mitutoyo, Tokyo, Japan).

After cleaning, enamel specimens (n=3) of

each group were submitted to microradiograph

exposure (20 kV and 20 mA, Softex, Tokyo,

Japan). The developed plates were analyzed

using a transmitted light microscope tted with

a 20 × objective. Two images per sample were

obtained using data acquisition (version 2012)

and interpreted using calculation (version

2006) software (Inspektor Research System;

Amsterdam, Netherlands). The mineral content

was calculated assuming 87 vol% of mineral

content for sound enamel and that the lesion

depth ends when enamel contains around 82.5%

of mineral volume [24,25].

Treatment of bovine enamel blocks with

uoride varnish doped with nanoparticles

The uoride varnish used in this study was

produced by FGM Produtos Odontológicos LTDA

(Joinville, Santa Catarina, Brazil), composed of

articial resin as a base and ethanol as a solvent

(6% NaF + 6% CaF2). All specimens were cleaned

first with Robinson brush/pumice stone and

treated with a thin layer of material by a micro

brush, following the three groups: experimental

varnish (VZ); experimental varnish + 1 wt%

silica gelatin (VZ-SiO2) and experimental varnish

+ 1 wt% niobium nanoparticles (VZ-Nb2O5)

(Table I).

After treatment, specimens were kept for

24 hours in relative humidity and then, varnishes

were removed with a scalpel blade, being

cleaned with an acetone-water (1:1) solution in

a microbrush [24].

Braz Dent Sci 2024 Apr/June;27 (2): e4246

Obeid AT et al.

Remineralizing potential of a fluoride v arnish modified by bioactiv e nanoparticles

Obeid AT et al. Remineralizing potential of a ﬂuoride varnish modiﬁed by

bioactive nanoparticles

pH-cycling regimen

After varnish removal, the blocks were

subjected to a pH-cycling model. For 8 days, the

blocks were kept for 22 hours in a remineralizing

solution and 2 hours in a demineralizing solution

at 37°C. The proportions of the de-remineralizing

solutions used were 6.25 ml/mm2 and

3.12 ml/mm2 of enamel, respectively. The solutions

were replaced on the fourth day of cycling with

new solutions, and after the end of the period of

8 days of cycling, the surface hardness of the post-

treatment enamel was evaluated [23].

Knoop hardness assessment

At the end of each time condition (after

treatments and after pH-cycling regimen), SH

was also determined (n = 10) in triplicate. Three

indentations at a standard distance from the

treatment area were made (100 μm) and then,

the mean values from the three indentations

and the percentage of surface hardness change

were calculated after treatments. The percentage

of surface hardness loss (%SHL) and recovery

(% SHR) was calculated after the pH-cycling

regimen, according to the formula:

% 1 0 0

SH baseline SH after pH cycling

SHL X

SH baseline

−

(1)

% 1 0 0

SH after pH cycling SH after artificial carieslesion

SHR X

SH baseline SH after artificial caries lesion

−

(2)

EDX analysis

For the EDX analysis, a total of 6 groups were

evaluated in different conditions: G1 (control

area of VZ), G2 (VZ after pH-cycling),

G3 (control area of VZ-SiO2), G4 (VZ-SiO2 after

pH-cycling), G5 (control area of VZ-Nb2O5) and

G6 (VZ-Nb2O5 after pH-cycling). Before the EDX

analysis, the specimens were kept in articial

saliva for 7 days to obtain ion shift between the

saliva and enamel specimens. The composition of

the articial saliva was: 0.2 mM glucose, 9.9 mM

NaCl, 1.5 mM CaCl2∙2H2O, 3 mM NH4Cl, 17 mM

KCl, 2 mM NaSCN, 2.4 mM K2HPO4, 3.3 mM urea,

2.4 mM NaH2PO4 and traces of ascorbic acid (pH

6.8) (all chemicals were purchased from Merck;

Darmstadt, Germany) [26]. The specimens were

sputter-coated with a thin layer of gold and

examined using scanning electron microscopy

(SEM) (Aspex Express; Fei Europe, Eindhoven,

Netherlands) at an accelerating voltage of

15–20 kV in relative vacuum. Elemental analysis

by EDX, which was fully integrated into the Aspex

Express SEM, was conducted over the entire area

to determine the relative amounts of Ca and P

by atomic percentage, carried out in standardless

mode. Ca/P ratio was calculated for all groups.

Statistical analysis

The data were statistically analyzed with

the Statistica software, version 10.0. Normal

distribution and equality of variances were

checked for all the variables using the Shapiro-

Wilk test. For enamel specimens, Two-way

ANOVA was performed to evaluate initial SH,

SH after the demineralization process and after

pH-cycling regimen, %SHL, %SHR and Ca/P

ratio, followed by a multiple comparison test

performed with the Tukey HSD test (p < 0.05).

RESULTS

Microhardness of the uoride varnishes

Initial surface hardness was not signicantly

different between groups (p = 0.179). Changes

in surface hardness values after each step are

shown in Table II.

The two-way ANOVA showed that there were

statistical differences between the varnishes, and

the moments (p < 0.05), revealing a signicant

interaction between the two study factors

(varnishes x moment). The incorporation of

niobium and silica nanoparticles into the uoride

varnish resulted in signicant differences in surface

hardness. Surface hardness after treatment was

higher for both experimental groups (VZ-SiO2 and

VZ-Nb2O5), showing signicant differences when

compared to the control group (VZ). The group

with the incorporation of Nb2O5 presented the

highest hardness values, differing from the others

Table I - Chemical composition of ﬂuoride varnishes

Group/

Manufacturer Composition Filler

VZ-control/ Artiﬁcial resin, ethanol, 6%

NaF and 6% CaF2

FGM

VZ-SiO2/Artiﬁcial resin, ethanol, 6%

NaF and 6% CaF2

1 wt.% SiO2

FGM

VZ-Nb2O5/Artiﬁcial resin, ethanol, 6%

NaF and 6% CaF2

1 wt.%

Nb2O5

FGM

Braz Dent Sci 2024 Apr/June;27 (2): e4246

Obeid AT et al.

Remineralizing potential of a fluoride v arnish modified by bioactiv e nanoparticles

Obeid AT et al. Remineralizing potential of a ﬂuoride varnish modiﬁed by

bioactive nanoparticles

(p=0.001), consequently recovering the hardness

in values (%) very close to the initial hardness

with sound enamel as shown in Table II.

Caries-like lesion evidence and EDX evalua-

tion of the bovine enamel blocks

Figure 1 shows a transversal microradiography

image (TMR), evidencing the production of

articial caries-like subsurface lesions without

surface erosion in the enamel blocks after being

submitted to the demineralizing solution.

For EDX, the areas of the sound enamel

blocks are represented in Figures 2a, b and c.

Figures 2d, e and f represent the demineralized

area of the enamel blocks. After treatment with

varnish and pH-cycling (Figures 2g, h and i),

the blocks treated with VZ-SiO2 and VZ-Nb2O5,

showed increased phosphate (P) and calcium

(Ca) ion deposition, being superior in the

presence of Nb2O5.

Figure 2 - EDX analysis of the diﬀerent groups: Sound blocks (a-VZ; b-VZ-SiO2; c-VZ-Nb2O5); Demineralized blocks (d-VZ; e-VZ-SiO2; f-VZ-

Nb2O5) and blocks treated with ﬂuoride varnish and after pH-cycling (g-VZ; h-VZ-SiO2; i-VZ-Nb2O5). Red arrows indicate phosphate (P) ion

deposition, and orange arrows indicate calcium (Ca) ion deposition.

Table II - Mean ± SD of SH after pH-cycling regimen, %SH loss and %SH recovery after pH-cycling regimen

Groups Initial SH

(Kg/mm2)

SH after deminer-

alization process

(Kg/mm2)

SH after pH-

cycling regimen

(Kg/mm2)

Percentage of SH

loss (%SH loss)-

after pH-cycling

regimen

Percentage of SH

recovery (%SH

recovery)-after pH-

cycling regimen

VZ 342.4±16.3a204.2±3.7a230.1±5.8a40.2±2.8a19.9±6.0a

VZ-SiO2333.7±11.1a203.8±1.9a303.0±7.1b38.8±2.3a77.6±9.5b

VZ-Nb2O5331.8±11.7a204.5±0.9a325.2±9.7c38.1±1.9a95.0±5.3c

Values in the same column with diﬀerent superscript lower − case letters signiﬁcantly diﬀer from each other (

< 0.05).

Figure 1 - TMR image evidencing an artiﬁcial caries-like subsurface

lesion. Black arrow shows the subsurface lesion.

Braz Dent Sci 2024 Apr/June;27 (2): e4246

Obeid AT et al.

Remineralizing potential of a fluoride v arnish modified by bioactiv e nanoparticles

Obeid AT et al. Remineralizing potential of a ﬂuoride varnish modiﬁed by

bioactive nanoparticles

DISCUSSION

Several remineralizing strategies have

made signicant progress in recent years, and

conventional methods for caries prevention,

such as topical uoride application, have been

shown to decrease demineralization by depositing

uoride in the enamel crystal lattice, reducing

its solubility [27]. This understanding of the

biomineralization process of dental hard tissue

has led to the development of biomimetic

remineralization strategies that mimic the

crystallization pathway using amorphous

precursors of hydroxyapatite (HAP) [28].

Fluoride treatment remains the standard

therapy for remineralization of white spot

lesions and has the highest level of scientific

evidence [29,30]. NaF varnishes are also valid

approaches for remineralization [9] and even

in enamel samples submitted to erosion and

abrasion protocols [31]. However, since uoride

does not penetrate deeper than the subsurface

demineralized zone [32], many researchers have

started developing new therapies, especially for

individuals at high risk for caries lesions who

require professional application of products

with a higher concentration of uoride. Thus,

most therapies aim to enhance the effects

of existing fluoride therapies rather than

replacing them [33,34]. The present study

aimed to evaluate the percentage composition

of enamel components after demineralization

and application of fluoride varnish modified

by bioactive nanoparticles. The bioactivity of

Nb2O5 allowed greater interaction between the

enamel and the material. Therefore, the null

hypothesis of this study was rejected.

One concern with bioactive materials is their

low mechanical strength [17]. Nanotechnology is

an emerging trend in dentistry, and new bioactive

materials with good mechanical properties, such

as Nb2O5 and SiO2, have been investigated and

used in the biomedical and dental elds [14,21].

Literature suggests that a minimal fraction of

bioactive llers should be used in composites to

promote remineralization through ion release,

and they should be combined with reinforcing

llers, such as whiskers [35,36]. In this study,

a concentration of only 1 wt% of nanoparticles

was chosen for better particle distribution

within the material. Surface microhardness

and EDX analysis were performed to assess the

effects of chemical/physical agents on hard

tissues of teeth [37] and to determine the Ca/P

ratio, analyzing the bioactivity potential of the

experimental varnishes.

The experimental varnishes (VZ-SiO2 and

VZ-Nb2O5) were able to remineralize the enamel

surface, inducing a signicant increase in hardness

recovery. These results are promising and suggest

that the incorporation of bioactive nanoparticles

into the uoride varnish adds an anticaries action,

allowing ion exchange with the solutions and

protecting the surface for a longer period.

In our study and similar studies [14], surface

microhardness decreased after demineralization

but increased after all fluoride varnish

applications. One interesting nding was that the

initial surface microhardness was almost reached

in the VZ-Nb2O5 group, which is important for

preventing enamel demineralization.

Most remineralizing strategies aim to

prolong the supersaturation periods by creating

stable systems that can supply bioavailable

calcium, phosphate, and uoride directly to the

lesion or the surrounding biolm [33]. During

remineralization, ion substitution takes place

in forming apatite, including the substitution

of calcium ions with magnesium and sodium,

substitution of hydroxyl sites with uoride and

chloride, and substitution of phosphate and

hydroxyl sites with carbonate. Therefore, minerals

other than calcium and phosphate can have a

significant influence on the remineralization

process, and considerable variation in apatite

properties can occur. For example, carbonate

substitution increases the solubility of apatite,

while fluoride substitution decreases its

solubility [38]. One significant challenge for

remineralizing therapies is to provide the right

concentration of minerals at the right time, as

elevated mineral concentration at the wrong time

could lead to unwanted surface precipitation,

limiting the efficacy of the therapy [33].

The VZ-Nb2O5 group in our study showed a

slow release of nanoparticles, which may favor

subsurface mineral gain and longevity of the

remineralizing treatment.

One limitation of the present study was

that mineral loss was only evaluated on the

surface, using surface hardness measurements.

Therefore, it would be interesting to assess cross-

sectional hardness to observe the progression

and determine the depth to which the material

is capable of remineralizing.

Braz Dent Sci 2024 Apr/June;27 (2): e4246

Obeid AT et al.

Remineralizing potential of a fluoride v arnish modified by bioactiv e nanoparticles

Obeid AT et al. Remineralizing potential of a ﬂuoride varnish modiﬁed by

bioactive nanoparticles

CONCLUSION

The experimental varnishes modified by

nanoparticles were able to signicantly increase

the remineralizing potential, being more effective

in improving surface remineralization, with the

one modied by Nb2O5 the group that presented

promising results.

Acknowledgements

The authors are thankful to Dr. Rodrigo L. de

O. Basso from Electron Microscopy Laboratory of

Federal University of Latin American Integration

(UNILA) for assisting with the energy dispersive

X-ray spectroscopy.

Author’s Contributions

ATO: Writing – Review & Editing, Writing

– Original Draft, Resources, Methodology,

Investigation and Conceptualization. MMACV:

Writing – Review & Editing, Writing – Original draft,

Visualization, Validation, Supervision, Methodology,

Investigation, Formal analysis, Data curation,

Conceptualization. TRLN: Writing – Review &

Editing, Resources, Methodology, Investigation,

Conceptualization. DLE: Writing – Review &

Editing, Writing – Original Draft, Methodology,

Investigation, Funding Acquisition. LSA: Writing –

Review & Editing, Visualization, Supervision. JFSB:

Writing – Review & Editing, Writing – Original

Draft, Visualization, Validation, Supervision,

Software, Resources, Project Administration,

Methodology, Investigation, Funding Acquisition,

Formal Analysis, Data Curation, Conceptualization.

Conict of Interest

The authors have no conicts of interest to

declare.

Funding

This study was nanced by the Coordenação

de Aperfeiçoamento Pessoal de Nível Superior -

Brasil (CAPES) - Finance Code 001.

Regulatory Statement

This study protocol was reviewed and

approved by the Animal Use Ethics Committee

from Bauru School of Dentistry, University of São

Paulo (#004/2020).

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Alyssa Teixeira Obeid

(Corresponding address)

Universidade de São Paulo, Faculdade de Odontologia de Bauru,

Departamento de Dentística, Endodontia e Materiais Odontológicos, Bauru,

SP, Brazil.

Email: alyssa.obeid@usp.br

Date submitted: 2024 Jan 29

Accept submission: 2024 Apr 23