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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">ResProt</journal-id>
      <journal-id journal-id-type="nlm-ta">JMIR Res Protoc</journal-id>
      <journal-title>JMIR Research Protocols</journal-title>
      <issn pub-type="epub">1929-0748</issn>
      <publisher>
        <publisher-name>JMIR Publications</publisher-name>
        <publisher-loc>Toronto, Canada</publisher-loc>
      </publisher>
    </journal-meta>
    <article-meta>
    <article-id pub-id-type="publisher-id">v7i1e26</article-id>
    <article-id pub-id-type="pmid">29374001</article-id>
    <article-id pub-id-type="doi">10.2196/resprot.9376</article-id>
    <article-categories>
      <subj-group subj-group-type="heading">
        <subject>Protocol</subject>
      </subj-group>
      <subj-group subj-group-type="article-type">
        <subject>Protocol</subject>
      </subj-group>
    </article-categories>
    <title-group>
      <article-title>Effect of a Titanium Tetrafluoride Varnish in the Prevention and Treatment of Carious Lesions in the Permanent Teeth of Children Living in a Fluoridated Region: Protocol for a Randomized Controlled Trial</article-title>
    </title-group>
    <contrib-group>
      <contrib contrib-type="editor">
        <name>
          <surname>Eysenbach</surname>
          <given-names>Gunther</given-names>
        </name>
      </contrib>
    </contrib-group>
    <contrib-group>
      <contrib contrib-type="reviewer">
        <name>
          <surname>Santacroce</surname>
          <given-names>Luigi</given-names>
        </name>
      </contrib>
      <contrib contrib-type="reviewer">
        <name>
          <surname>Skelton</surname>
          <given-names>Mary Caroline</given-names>
        </name>
      </contrib>
    </contrib-group>
    <contrib-group>
      <contrib contrib-type="author" id="contrib1">
        <name name-style="western">
          <surname>Souza</surname>
          <given-names>Beatriz Martines</given-names>
        </name>
        <degrees>DDS, MSc</degrees>
        <xref rid="aff1" ref-type="aff">1</xref>
        <ext-link ext-link-type="orcid">http://orcid.org/0000-0003-3952-1623</ext-link>
      </contrib>
      <contrib contrib-type="author" id="contrib2">
        <name name-style="western">
          <surname>Santos</surname>
          <given-names>Daiana Moreli Soares</given-names>
        </name>
        <degrees>BSc (Biology)</degrees>
        <xref rid="aff1" ref-type="aff">1</xref>
        <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-9113-4076</ext-link>
      </contrib>
      <contrib contrib-type="author" id="contrib3">
        <name name-style="western">
          <surname>Braga</surname>
          <given-names>Aline Silva</given-names>
        </name>
        <degrees>BSc (Biology), MSc</degrees>
        <xref rid="aff1" ref-type="aff">1</xref>
        <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-9331-1531</ext-link>
      </contrib>
      <contrib contrib-type="author" id="contrib4">
        <name name-style="western">
          <surname>Santos</surname>
          <given-names>Natália Mello Dos</given-names>
        </name>
        <degrees>DDS, MSc</degrees>
        <xref rid="aff2" ref-type="aff">2</xref>
        <ext-link ext-link-type="orcid">http://orcid.org/0000-0003-2921-0733</ext-link>
      </contrib>
      <contrib contrib-type="author" id="contrib5">
        <name name-style="western">
          <surname>Rios</surname>
          <given-names>Daniela</given-names>
        </name>
        <degrees>DDS, MSc, PhD</degrees>
        <xref rid="aff2" ref-type="aff">2</xref>
        <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-9162-3654</ext-link>
      </contrib>
      <contrib contrib-type="author" id="contrib6">
        <name name-style="western">
          <surname>Buzalaf</surname>
          <given-names>Marilia Afonso Rabelo</given-names>
        </name>
        <degrees>DDS, MSc, PhD</degrees>
        <xref rid="aff1" ref-type="aff">1</xref>
        <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-5985-3951</ext-link>
      </contrib>
      <contrib contrib-type="author" id="contrib7" corresp="yes">
      <name name-style="western">
        <surname>Magalhães</surname>
        <given-names>Ana Carolina</given-names>
      </name>
      <degrees>DDS, MSc, PhD</degrees>
      <xref rid="aff1" ref-type="aff">1</xref>
      <address>
        <institution>Department of Biological Sciences</institution>
        <institution>Bauru School of Dentistry</institution>
        <institution>University of São Paulo</institution>
        <addr-line>Al Octávio Pinheiro Brisola, 9-75</addr-line>
        <addr-line>Bauru, 17012-901</addr-line>
        <country>Brazil</country>
        <phone>55 14 32358497</phone>
        <email>acm@usp.br</email>
      </address>  
      <ext-link ext-link-type="orcid">http://orcid.org/0000-0002-6413-5348</ext-link></contrib>
    </contrib-group>
    <aff id="aff1">
    <sup>1</sup>
    <institution>Department of Biological Sciences</institution>
    <institution>Bauru School of Dentistry</institution>  
    <institution>University of São Paulo</institution>  
    <addr-line>Bauru</addr-line>
    <country>Brazil</country></aff>
    <aff id="aff2">
    <sup>2</sup>
    <institution>Department of Pediatric Dentistry, Orthodontic and Public Health</institution>
    <institution>Bauru School of Dentistry</institution>  
    <institution>University of São Paulo</institution>  
    <addr-line>Bauru</addr-line>
    <country>Brazil</country></aff>
    <author-notes>
      <corresp>Corresponding Author: Ana Carolina Magalhães 
      <email>acm@usp.br</email></corresp>
    </author-notes>
    <pub-date pub-type="collection"><month>01</month><year>2018</year></pub-date>
    <pub-date pub-type="epub">
      <day>26</day>
      <month>01</month>
      <year>2018</year>
    </pub-date>
    <volume>7</volume>
    <issue>1</issue>
    <elocation-id>e26</elocation-id>
    <!--history from ojs - api-xml-->
    <history>
      <date date-type="received">
        <day>9</day>
        <month>11</month>
        <year>2017</year>
      </date>
      <date date-type="rev-request">
        <day>13</day>
        <month>12</month>
        <year>2017</year>
      </date>
      <date date-type="rev-recd">
        <day>15</day>
        <month>12</month>
        <year>2017</year>
      </date>
      <date date-type="accepted">
        <day>16</day>
        <month>12</month>
        <year>2017</year>
      </date>
    </history>
    <!--(c) the authors - correct author names and publication date here if necessary. Date in form ', dd.mm.yyyy' after jmir.org-->
    <copyright-statement>©Beatriz Martines Souza, Daiana Moreli Soares Santos, Aline Silva Braga, Natália Mello Dos Santos, Daniela Rios, Marilia Afonso Rabelo Buzalaf, Ana Carolina Magalhães. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 26.01.2018.</copyright-statement>
    <copyright-year>2018</copyright-year>
    <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
      <p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Research Protocols, is properly cited. The complete bibliographic information, a link to the original publication on http://www.researchprotocols.org, as well as this copyright and license information must be included.</p>
    </license>  
    <self-uri xlink:href="http://www.researchprotocols.org/2018/1/e26/" xlink:type="simple"/>
    <abstract>
      <sec sec-type="background">
        <title>Background</title>
        <p>Titanium tetrafluoride (TiF<sub>4</sub>) has regained interest due to new formulations that have been shown to be more effective against tooth demineralization than sodium fluoride (NaF) formulations in vitro and in situ.</p>
      </sec>
      <sec sec-type="objective">
        <title>Objective</title>
        <p>The aim of this study is to evaluate the effect of two types of varnishes (4% TiF<sub>4</sub> and a commercial 5% NaF) on the prevention of carious lesions and the treatment of noncavitated enamel carious lesions in the permanent teeth of children living in a fluoridated area.</p>
      </sec>
      <sec sec-type="methods">
        <title>Methods</title>
        <p>This randomized, controlled, parallel and single-blind clinical trial involves 63 children, 6-7 years old, living in Bauru, São Paulo, Brazil. Children were selected according to their caries activity (ie, presence of at least 1 tooth with a Nyvad score of 1) and randomly divided into the following treatment categories: 4% TiF<sub>4</sub> varnish (2.45 % F<sup>-</sup>, pH 1, FGM); 5% NaF varnish (2.26% F<sup>-</sup>, pH 5, Duraphat, Colgate) and control (placebo varnish, pH 5, FGM). The varnishes will be applied on all permanent teeth, once a week for 4 weeks and they will be reapplied only once 6 and 12 months after the study begins. Two calibrated examiners will carry out the clinical examination (International Caries Detection and Assessment System [ICDAS] and Nyvad indexes, kappa&#62;.8) at baseline, before the first application, after the 1st, 6th, 12th, and 18th month of the study begins. Furthermore, quantitative fluorescence changes will be measured using Quantitative Light-Induced Fluorescence (QLF). The degree of patient satisfaction with the treatment will also be computed. The data will undergo statistical analysis (<italic>P</italic>&#60;.05).</p>
      </sec>
      <sec sec-type="results">
        <title>Results</title>
        <p>This ongoing study is funded by funding agencies from Brazil (São Paulo Research Foundation, FAPESP-015/14149-1, and National Council for Scientific and Technological Development, CNPq-401313/2016-6). We expect to confirm the efficacy of TiF<sub>4</sub> on the prevention and treatment of carious lesions by comparing it to NaF varnish. The subjects are under 1 month evaluation and the dropout was about 8%. No differences between the treatments have been detected at the first month so far (<italic>P</italic>&#62;.05).</p>
      </sec>
      <sec sec-type="conclusions">
        <title>Conclusions</title>
        <p>If our hypothesis is confirmed, TiF<sub>4</sub> varnish can be marketed and applied at the individual level and used in community programs to control dental caries.</p>
      </sec>
      <sec sec-type="Trial Registration">
        <title>Trial Registration</title>
        <p>Brazilian Clinical Trials Registry: RBR-5VWJ4Y; http://www.ensaiosclinicos.gov.br/rg/?q=RBR-5VWJ4Y (Archived by WebCite at http://www.webcitation.org/6wUurEnm7)</p>
      </sec>
    </abstract>
    <kwd-group>
      <kwd>clinical trial</kwd>
      <kwd>dental caries</kwd>
      <kwd>topical fluorides</kwd>
    </kwd-group></article-meta>
  </front>
  <body>
    <sec sec-type="introduction">
      <title>Introduction</title>
      <p>Fluoride varnishes are a feasible approach for preventing and treating carious lesions at the individual level and in public health programs, due to its good cost-benefit compared to initial carious lesions restorations, when they eventually progress to cavitation and have a significant negative impact in quality of life [<xref ref-type="bibr" rid="ref1">1</xref>,<xref ref-type="bibr" rid="ref2">2</xref>].</p>
      <p>Due to the polarization of caries [<xref ref-type="bibr" rid="ref3">3</xref>] and inequality in health services access, treatment is available to only a small portion of the population [<xref ref-type="bibr" rid="ref3">3</xref>,<xref ref-type="bibr" rid="ref4">4</xref>]. This fact requires the attention of authorities and appropriate public health interventions [<xref ref-type="bibr" rid="ref4">4</xref>,<xref ref-type="bibr" rid="ref5">5</xref>]. Based on this new panorama of the disease, researchers have sought to improve the effect of conventional fluorides or alternatively to test nonconventional fluorides (eg, fluorides [F] containing polyvalent metals, such as stannous fluoride [SnF<sub>2</sub>] and titanium tetrafluoride [TiF<sub>4</sub>]) [<xref ref-type="bibr" rid="ref6">6</xref>,<xref ref-type="bibr" rid="ref7">7</xref>].</p>
      <p>Several in vitro and in situ studies have shown that an experimental 4% TiF<sub>4</sub> is more effective than NaF at reducing demineralization and improving remineralization [<xref ref-type="bibr" rid="ref7">7</xref>-<xref ref-type="bibr" rid="ref9">9</xref>]. The titanium ions from TiF<sub>4</sub> react with dental apatite, forming an acid resistant, glaze-like layer that is rich in hydrated titanium phosphate and titanium dioxide [<xref ref-type="bibr" rid="ref10">10</xref>]. Furthermore, TiF<sub>4</sub> varnish induces a higher deposition of calcium fluoride (CaF<sub>2</sub>) than NaF varnish on both intact and demineralized enamel surface [<xref ref-type="bibr" rid="ref10">10</xref>].</p>
      <p>Recent in situ study demonstrated that 4% TiF<sub>4</sub> varnish was the only treatment capable of improving enamel remineralization regardless of cariogenic activity, while NaF varnish failed in preventing further demineralization under high cariogenic activity [<xref ref-type="bibr" rid="ref7">7</xref>]. This result supports the hypothesis of the present study that TiF<sub>4</sub> varnish could be more effective than NaF varnish in preventing and treating carious lesions in the permanent teeth of children living in a fluoridated area.</p>
      <p>The aim of this clinical protocol is to evaluate the effect of 4% TiF<sub>4</sub> varnish compared to a commercial 5% NaF varnish on the prevention of carious lesions and the treatment of noncavitated enamel carious lesions in the permanent teeth of children living in a fluoridated area.</p>
    </sec>
    <sec sec-type="methods">
      <title>Methods</title>
      <sec>
        <title>Ethical Aspects</title>
        <p>The protocol of this study was submitted and approved by the local ethics committee (Number: 59787116.2.0000.5417, Ethics Committee of the Bauru School of Dentistry, University of São Paulo, Brazil) and by the registration of clinical research in the Brazilian Clinical Trials Registry (Number: RBR-5VWJ4Y). The research protocol was also approved by the Municipal Secretariat for Education of Bauru (São Paulo, Brazil) and by the 5 municipal schools (see <xref ref-type="table" rid="table1">Table 1</xref>) enrolled in the study. Thereafter, the parents and/or guardians responsible for the study participants (eg, children aged 6-7 years) received and signed an informed consent form prior to their involvement in the research. The children also received a consent form, with age-appropriate language, explaining how the research would be conducted. The children were free to accept or reject participation in the study. Upon receiving approval and consent from all involved parties, the study began.</p>
      </sec>
      <sec>
        <title>Study Design</title>
        <p>This is a randomized, controlled, parallel, single-blind, and three-armed (ie, 4% TiF<sub>4</sub> varnish, 5% NaF varnish and placebo varnish) clinical trial with a duration of 18 months. It involves 63 children (37 males and 26 females) between 6-7 years of age, coming from public schools of Bauru city, an area that is optimally fluoridated. An experimental number of 20 children per treatment group was previously calculated considering an α error of 5%, β error of 20%, a dropout rate of 30%, and a caries incidence rate after a period of 2 years of 15% for fluoride group and 42% for control group [<xref ref-type="bibr" rid="ref11">11</xref>].</p>
        <p>Children were selected according to their caries activity (ie, at least 1 active white spot lesion present on the smooth surface of their permanent dentition with a score of 1 according to the Nyvad index [<xref ref-type="bibr" rid="ref12">12</xref>]) and randomly allocated to one of the 3 treatment options ensuring stratified block randomization into each group: 4% TiF<sub>4</sub> varnish (2.45% F<sup>-</sup>, pH 1, FGM); 5% NaF varnish (2.26% F<sup>-</sup>, pH 5, Duraphat, Colgate) and control (placebo varnish, pH 5, FGM).</p>
        <table-wrap position="float" id="table1">
          <label>Table 1</label>
          <caption>
            <p>Distribution of selected schools according to the regions of Bauru city (São Paulo, Brazil).</p>
          </caption>
          <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
            <col width="150"/>
            <col width="850"/>
            <thead>
              <tr valign="top">
                <td>Region</td>
                <td>Name of school</td>
              </tr>
            </thead>
            <tbody>
              <tr valign="top">
                <td rowspan="2">North</td>
                <td>EMEF<sup>a</sup> José Romão</td>
              </tr>
              <tr valign="top">
                <td>EMEF Geraldo Arone</td>
              </tr>
              <tr valign="top">
                <td>South</td>
                <td>EMEF Santa Maria</td>
              </tr>
              <tr valign="top">
                <td>East</td>
                <td>EMEF Thereza Tarzia - Irmã Rosamaria Tarzia</td>
              </tr>
              <tr valign="top">
                <td>West</td>
                <td>EMEF Ivan Engler de Almeida</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="table1fn1">
              <p><sup>a</sup>EMEF: municipal school of fundamental education.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <fig id="figure1" position="float">
          <label>Figure 1</label>
          <caption>
            <p>Flowchart of the study.</p>
          </caption>
          <graphic xlink:href="resprot_v7i1e26_fig1.jpg" alt-version="no" mimetype="image" position="float" xlink:type="simple"/>
        </fig>
        <p>The treatment was conducted as described below. The teeth were submitted to clinical examination (using the International Caries Detection and Assessment System [ICDAS] and Nyvad indexes), and quantitative fluorescence changes were monitored by a quantitative light-induced fluorescence (QLF) device. The analyses were conducted after the first month and they will be carried out at the 6th, 12th, and 18th month of the study. <xref ref-type="fig" rid="figure1">Figure 1</xref> summarizes the study protocol.</p>
      </sec>
      <sec>
        <title>Baseline Analysis</title>
        <p>Two trained examiners (inter- and intraexaminer agreement, kappa&#62;.8), not involved in the treatment application, are responsible for examining the children (NMS and BMS). The children were selected based on the analysis of smooth surfaces using the Nyvad index [<xref ref-type="bibr" rid="ref12">12</xref>]. Only children aged 6-7 years, presenting at least 1 smooth surface with active carious lesions and the signed consents, were selected. The exclusion criteria were: children under orthodontic treatment; those who participated in another clinical study 3 months prior to the present study; those who underwent professional fluoride application 6 months prior to the present study; those under treatment with antibiotics or some other type of medicine (eg, patients with chronic diseases); or those with periodontal disease.</p>
        <p>The distinction between active and inactive carious lesions was done through visual and tactile inspection. The active white spot lesions were defined as having a rough and opaque white surface [<xref ref-type="bibr" rid="ref13">13</xref>]. All white spot lesions were further analyzed using QLF [<xref ref-type="bibr" rid="ref14">14</xref>]. Furthermore, all permanent teeth surfaces were analyzed using ICDAS, which is a method of caries detection and evaluation that classifies the stages of the caries process [<xref ref-type="bibr" rid="ref15">15</xref>]. The decayed, missing, filled teeth index (DMFT) was applied for the primary teeth (this data will be included in the regression analysis to check the influence of other variable on the results).</p>
      </sec>
      <sec>
        <title>Treatment</title>
        <p>All children received instruction on cariogenic diets and oral hygiene, and were given supervised tooth brushing. The researchers provided new toothbrushes (Colgate Classic, Colgate-Palmolive), dental floss (Colgate, Colgate-Palmolive), and fluoride toothpastes (Colgate, 1450 ppm F<sup>-</sup> as monofluoride phosphate [MFP], Colgate-Palmolive). The oral hygiene kit will be replaced every 3 months during the study.</p>
        <p>The varnishes were applied on all permanent teeth once a week for the first 4 consecutive weeks [<xref ref-type="bibr" rid="ref16">16</xref>] and they will be reapplied once at the 6th and 12th month of the study [<xref ref-type="bibr" rid="ref17">17</xref>] by ASB. The application was done using a microbrush, under natural light, following the clinical steps:</p>
        <list list-type="order">
          <list-item>
            <p>Supervised tooth brushing by DMSS.</p>
          </list-item>
          <list-item>
            <p>Relative isolation of teeth area with cotton rolls.</p>
          </list-item>
          <list-item>
            <p>Drying of the teeth surfaces using sterile gauze.</p>
          </list-item>
          <list-item>
            <p>Varnish application according to the manufacturer’s instructions.</p>
          </list-item>
          <list-item>
            <p>Waiting for 5 minutes for solvent evaporation.</p>
          </list-item>
          <list-item>
            <p>Removal of the cotton rolls.</p>
          </list-item>
        </list>
        <p>The treatments were done during the afternoon. The children were instructed not to ingest liquid for 30 min, to have soft meals and to perform oral hygiene 4 hours after the application.</p>
        <p>After each application, a visual scale (<xref ref-type="fig" rid="figure2">Figure 2</xref>) (Wong-Baker Pain Scale [WBPS]) was applied to assess the degree of patient satisfaction with the treatment. The scale is known to be one of the most effective tools for self-rated child pain [<xref ref-type="bibr" rid="ref18">18</xref>]. The mean result of the first four varnish applications is described in the Results section.</p>
      </sec>
      <sec>
        <title>Clinical Examination</title>
        <p>Clinical examinations were performed after dental hygiene activities, based on the clinical criteria for caries diagnosis outlined by Nyvad et al [<xref ref-type="bibr" rid="ref19">19</xref>], which were modified as shown in <xref ref-type="table" rid="table2">Table 2</xref> [<xref ref-type="bibr" rid="ref12">12</xref>]. Only the smooth surfaces of all permanent teeth were considered and the clinical examination was carried out in an illuminated environment, using clinical probe and mirror, and sterile gauzes. In addition, the ICDAS index was used to assess all surfaces at baseline and will be applied again at the 18th month (<xref ref-type="table" rid="table3">Table 3</xref>).</p>
        <p>The progression of white spot lesion occurs when the noncavitated lesion becomes a cavity (untreated cavity or restored tooth) or when a healthy surface is transformed into an active lesion (cavitated or not). The regression is defined as when the initial active white spot lesion is transformed into an inactive carious lesion or healthy surface. The data (degrees of freedom [df] = baseline Nyvad’s score – 1 month Nyvad’s score) was analyzed using a Kruskal-Wallis test.</p>
        <fig id="figure2" position="float">
          <label>Figure 2</label>
          <caption>
            <p>The Wong-Baker Visual Scale (WBPS), where 0 is very good (no pain/discomfort) and 10 is highly dissatisfied (worst possible pain/discomfort).</p>
          </caption>
          <graphic xlink:href="resprot_v7i1e26_fig2.jpg" alt-version="no" mimetype="image" position="float" xlink:type="simple"/>
        </fig>
        <table-wrap position="float" id="table2">
          <label>Table 2</label>
          <caption>
            <p>Modified Nyvad’s scores [<xref ref-type="bibr" rid="ref12">12</xref>].</p>
          </caption>
          <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
            <col width="150"/>
            <col width="850"/>
            <thead>
              <tr valign="top">
                <td>Score</td>
                <td>Description</td>
              </tr>
            </thead>
            <tbody>
              <tr valign="top">
                <td>Score 0</td>
                <td>Sound enamel</td>
              </tr>
              <tr valign="top">
                <td>Score 1</td>
                <td>Active white spot lesion – not cavitated</td>
              </tr>
              <tr valign="top">
                <td>Score 2</td>
                <td>Inactive white spot lesion – not cavitated</td>
              </tr>
              <tr valign="top">
                <td>Score 3</td>
                <td>Cavitated enamel (tooth with cavity, restored, or extracted)</td>
              </tr>
            </tbody>
          </table>
        </table-wrap>
        <table-wrap position="float" id="table3">
          <label>Table 3</label>
          <caption>
            <p>International Caries Detection and Assessment System (ICDAS) scores [<xref ref-type="bibr" rid="ref15">15</xref>].</p>
          </caption>
          <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
            <col width="150"/>
            <col width="850"/>
            <thead>
              <tr valign="top">
                <td>Score</td>
                <td>Classification criteria</td>
              </tr>
            </thead>
            <tbody>
              <tr valign="top">
                <td>0</td>
                <td>No or subtle change in enamel translucency after prolonged drying (5s) in area of biofilm accumulation</td>
              </tr>
              <tr valign="top">
                <td>1</td>
                <td>Visible white spot after drying (no loss of surface continuity) or pigmentation restricted to confines of a pit or fissure</td>
              </tr>
              <tr valign="top">
                <td>2</td>
                <td>White spot visible on wet surface (no loss of surface continuity) or pigmentation that extrapolates confines of a pit or fissure</td>
              </tr>
              <tr valign="top">
                <td>3</td>
                <td>Localized cavitation (or loss of continuity) in opaque or pigmented enamel</td>
              </tr>
              <tr valign="top">
                <td>4</td>
                <td>Underlying dark shadow from dentin, with or without cavitation of enamel</td>
              </tr>
              <tr valign="top">
                <td>5</td>
                <td>Cavitated enamel with exposure of the underlying dentin, involving up to half of the analyzed surface</td>
              </tr>
              <tr valign="top">
                <td>6</td>
                <td>Cavitated enamel with exposure of the underlying dentin, involving more than half of the analyzed surface</td>
              </tr>
            </tbody>
          </table>
        </table-wrap>
      </sec>
      <sec>
        <title>Quantitative Light-Induced Fluorescence</title>
        <p>QLF is applied to measure the changes in the enamel fluorescence of white spot lesions and to quantify its reversal or progression. A xenon arc lamp is used as a light source, and an optical filter system, producing blue light with a maximum wavelength of 370 nm, is connected to the microscope by a liquid light guide (Inspektor Research Systems BV, Amsterdam, The Netherlands). The fluorescence emitted by the tooth is collected with a charged coupled device (CCD)-video microcamera (Panasonic WV-KS 152, Matsushita Electric Industrial Co, Ltd, Osaka, Japan) equipped with high pass yellow filter (γ&#62;520 nm) to exclude any excitation or ambient light that may reach the detector and a special dental mirror to reflect the image of the lesion connected to the camera [<xref ref-type="bibr" rid="ref14">14</xref>].</p>
        <p>After drying the tooth surface (for 5 s), images of clinically detected white spot lesions are obtained by QLF, in a completely dark environment. A computer program (Software Inspektor QLF 2.00f; Inspektor Research System BV, Amsterdam, The Netherlands) is utilized to display, store, browse, and analyze the images. The QLF parameters are: 1) the area of the lesion (white spot area [WS], mm<sup>2</sup>) that is the sum of all points within the lesion with fluorescence loss &#62; 5%; and 2) the mean fluorescence loss (ΔF, %, detection threshold of 5%) [<xref ref-type="bibr" rid="ref20">20</xref>].</p>
        <p>The QLF analysis was performed at baseline and after 1 month. The differences between the 1 month and baseline values were calculated as follows: ΔWS area = WS area baseline – WS area after 1 month (the same for ΔΔF), where ΔWS is the variation of the white spot lesion area and ΔΔF is the variation of the mean fluorescence loss. The data were analyzed using the Kruskal-Wallis test. This analysis will be repeated after the 6th, 12th, and 18th months of the treatment by BMS.</p>
      </sec>
      <sec>
        <title>Statistical Analysis</title>
        <p>The data will be subjected to statistical analysis using the GraphPad Instat and Prism (version 5.0 software) for Windows (GraphPad Software; San Diego, CA, USA). Firstly, the data will be checked for normality and homogeneity. A parametric or a similar nonparametric test will be applied to compare the treatments with respect to: 1) the prevention of new carious lesions (ICDAS and Nyvad indexes); 2) regression or progression of previous active white spot lesions using the Nyvad index; 3) regression or progression (gain or loss of fluorescence, respectively) of previously active white spot lesions using QLF (at 0, 1, 6, 12 and 18 months).</p>
      </sec>
    </sec>
    <sec sec-type="results">
      <title>Results</title>
      <p>This protocol refers to an ongoing clinical study funded by the São Paulo Research Foundation (FAPESP-2015/14149-1) and the National Council for Scientific and Technological Development (CNPq-401313/2016-6).</p>
      <p>Treatment, Clinical Examination and Quantitative Light-Induced Fluorescence</p>
      <p><xref ref-type="fig" rid="figure1">Figure 1</xref> shows the number of children by school enrolled in the research so far. All enrolled children (n=63) were underwent 4 weeks of treatment and almost all of them (n=58) were analyzed after 1 month. Five out of 63 children (8%) dropped out after the first month of analysis (n total=58). No significant differences in caries prevention, regression or progression were found among the treatments at the first month (<xref ref-type="table" rid="table4">Tables 4</xref> and <xref ref-type="table" rid="table5">5</xref>). The degree of patient satisfaction with the treatment after the varnish applications is displayed in <xref ref-type="table" rid="table6">Tables 6</xref> and <xref ref-type="table" rid="table7">7</xref>.</p>
      <table-wrap position="float" id="table4">
        <label>Table 4</label>
        <caption>
          <p>Nyvad’s scores [<xref ref-type="bibr" rid="ref12">12</xref>] at the baseline and after 1 month of treatment (final) for TiF<sub>4</sub>, NaF and placebo treatments.</p>
        </caption>
        <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
          <col width="230"/>
          <col width="130"/>
          <col width="140"/>
          <col width="0"/>
          <col width="130"/>
          <col width="140"/>
          <col width="0"/>
          <col width="130"/>
          <col width="100"/>
          <thead>
            <tr valign="top">
              <td rowspan="2">Measures</td>
              <td colspan="3">TiF<sub>4</sub></td>
              <td colspan="3">NaF</td>
              <td colspan="2">Placebo</td>
            </tr>
            <tr valign="top">
              <td>Baseline</td>
              <td>Final</td>
              <td colspan="2">Baseline</td>
              <td>Final</td>
              <td colspan="2">Baseline</td>
              <td>Final</td>
            </tr>
          </thead>
          <tbody>
            <tr valign="bottom">
              <td>Nyvad index, mean±SD</td>
              <td>1.0±0.00</td>
              <td>1.0±0.00</td>
              <td colspan="2">0.97±0.15</td>
              <td>1.03±0.15<sup>a</sup></td>
              <td colspan="2">0.99±0.06</td>
              <td>1.08±0.24<sup>b</sup></td>
            </tr>
            <tr valign="bottom">
              <td>Df<sup>c</sup>, median (min-max)</td>
              <td colspan="3">0.0 (0.0 to 0.0)</td>
              <td colspan="3">0.0 (–0.7 to 0.0)</td>
              <td colspan="2">0.0 (–1.0 to 0.0)</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="table4fn1">
            <p><sup>a</sup>One patient presented two teeth that progressed from score 0 to 1 and 1 patient had one lesion that progressed from score 1 to 3.</p>
          </fn>
          <fn id="table4fn2">
            <p><sup>b</sup>One patient presented one tooth that progressed from score 0 to 3 and one patient had one lesion that progressed from score 1 to 3.</p>
          </fn>
          <fn id="table4fn3">
            <p><sup>c</sup>Df: degrees of freedom. Df = baseline – final value, where positive values indicate regression and negative values indicate lesions progression. Kruskal-Wallis Test (<italic>p</italic>=.39).</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <table-wrap position="float" id="table5">
        <label>Table 5</label>
        <caption>
          <p>Median (minimum-maximum values) obtained in quantitative light-induced fluorescence (QLF) analysis at the first month compared to the baseline.</p>
        </caption>
        <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
          <col width="325"/>
          <col width="375"/>
          <col width="296"/>
          <thead>
            <tr valign="bottom">
              <td>Type of varnish</td>
              <td>ΔWS area (mm<sup>2</sup>)<sup>a,b</sup></td>
              <td>ΔΔF (%)<sup>b,c</sup></td>
            </tr>
          </thead>
          <tbody>
            <tr valign="top">
              <td>TiF<sub>4</sub></td>
              <td>0.01 (–9.15 to 1.19)</td>
              <td>–1.29 (–16.30 to 4.74)</td>
            </tr>
            <tr valign="top">
              <td>NaF</td>
              <td>0.17 (–2.38 to 1.47)</td>
              <td>–0.55 (–5.80 to 6.10)</td>
            </tr>
            <tr valign="top">
              <td>Placebo</td>
              <td>0.19 (–1.14 to 4.36)</td>
              <td>–0.23 (–5.17 to 5.10)</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="table5fn1">
            <p><sup>a</sup>ΔWS: variation of the white spot lesion area. For ΔWS, negative values mean progression (demineralization), and positive values, regression (remineralization). The opposite is valid for ΔΔF.</p>
          </fn>
          <fn id="table5fn2">
            <p><sup>b</sup>Kruskal-Wallis Test (<italic>p</italic>=.59 and <italic>p</italic>=.45, respectively).</p>
          </fn>
          <fn id="table5fn3">
            <p><sup>c</sup>ΔΔF: variation of the mean fluorescence loss.</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <table-wrap position="float" id="table6">
        <label>Table 6</label>
        <caption>
          <p>Mean percentage (%) of the degree of patient satisfaction after the first 4 applications of the TiF<sub>4</sub>, NaF and placebo varnishes using the Wong-Baker Pain Scale.</p>
        </caption>
        <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
          <col width="230"/>
          <col width="270"/>
          <col width="270"/>
          <col width="230"/>
          <thead>
            <tr valign="top">
              <td>Wong-Baker Pain Scale</td>
              <td colspan="3">Type of varnish, mean±SD (%)</td>
            </tr>
            <tr valign="top">
              <td><break/></td>
              <td>TiF<sub>4</sub></td>
              <td>NaF</td>
              <td>Placebo</td>
            </tr>
          </thead>
          <tbody>
            <tr valign="top">
              <td>0</td>
              <td>75±8</td>
              <td>86±6</td>
              <td>76±11</td>
            </tr>
            <tr valign="top">
              <td>2</td>
              <td>20±5</td>
              <td>12±6</td>
              <td>17±9</td>
            </tr>
            <tr valign="top">
              <td>4</td>
              <td>5±4</td>
              <td>2±3</td>
              <td>3±3</td>
            </tr>
            <tr valign="top">
              <td>6</td>
              <td>0±0</td>
              <td>0±0</td>
              <td>3±3</td>
            </tr>
            <tr valign="top">
              <td>8</td>
              <td>0±0</td>
              <td>0±0</td>
              <td>0±0</td>
            </tr>
            <tr valign="top">
              <td>10</td>
              <td>0±0</td>
              <td>0±0</td>
              <td>1±3</td>
            </tr>
          </tbody>
        </table>
      </table-wrap>
      <table-wrap position="float" id="table7">
        <label>Table 7</label>
        <caption>
          <p>Number of patients included in the analysis of satisfaction (Wong-Baker Pain scale) after the first four varnish applications.</p>
        </caption>
        <table width="1000" cellpadding="5" cellspacing="0" border="1" rules="groups" frame="hsides">
          <col width="230"/>
          <col width="60"/>
          <col width="60"/>
          <col width="60"/>
          <col width="90"/>
          <col width="60"/>
          <col width="60"/>
          <col width="60"/>
          <col width="90"/>
          <col width="60"/>
          <col width="60"/>
          <col width="60"/>
          <col width="50"/>
          <thead>
          <tr valign="top">
            <td>Wong-Baker Pain Scale</td>
            <td colspan="12">Number of patients by varnish type</td>
          </tr>
          <tr valign="top">
            <td><break/></td>
            <td colspan="4">TiF<sub>4</sub></td>
            <td colspan="4">NaF</td>
            <td colspan="4">Placebo</td>
          </tr>
            <tr valign="bottom">
              <td><break/></td>
              <td>1st<sup>a</sup></td>
              <td>2nd</td>
              <td>3rd</td>
              <td>4th</td>
              <td>1st</td>
              <td>2nd</td>
              <td>3rd</td>
              <td>4th</td>
              <td>1st</td>
              <td>2nd</td>
              <td>3rd</td>
              <td>4th</td>
            </tr>
          </thead>
          <tbody>
            <tr valign="top">
              <td>0</td>
              <td>18</td>
              <td>15</td>
              <td>16</td>
              <td>14</td>
              <td>19</td>
              <td>17</td>
              <td>19</td>
              <td>17</td>
              <td>18</td>
              <td>16</td>
              <td>13</td>
              <td>14</td>
            </tr>
            <tr valign="top">
              <td>2</td>
              <td>3</td>
              <td>5</td>
              <td>4</td>
              <td>5</td>
              <td>1</td>
              <td>3</td>
              <td>2</td>
              <td>4</td>
              <td>1</td>
              <td>4</td>
              <td>5</td>
              <td>4</td>
            </tr>
            <tr valign="top">
              <td>4</td>
              <td>0</td>
              <td>1</td>
              <td>1</td>
              <td>2</td>
              <td>1</td>
              <td>1</td>
              <td>0</td>
              <td>0</td>
              <td>1</td>
              <td>0</td>
              <td>0</td>
              <td>1</td>
            </tr>
            <tr valign="top">
              <td>6</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>1</td>
              <td>1</td>
            </tr>
            <tr valign="top">
              <td>8</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
            </tr>
            <tr valign="top">
              <td>10</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>0</td>
              <td>1</td>
              <td>0</td>
            </tr>
            <tr valign="top">
              <td>Total</td>
              <td>21</td>
              <td>21</td>
              <td>21</td>
              <td>21</td>
              <td>21</td>
              <td>21</td>
              <td>21</td>
              <td>21</td>
              <td>20</td>
              <td>20</td>
              <td>20</td>
              <td>20</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="table7fn1">
            <p><sup>a</sup>The first (1st), the second (2nd), the third (3rd) and the fourth (4th) varnish application.</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <p>We expect to confirm the efficacy of the TiF<sub>4</sub> varnish compared to one based on NaF for the prevention and treatment of carious lesions at the end of the present study (18 months) as we have previously found under in vitro and in situ protocols.</p>
    </sec>
    <sec sec-type="discussion">
      <title>Discussion</title>
      <p>Previous systematic reviews have shown no significant differences between the anticaries performances of fluoride (mainly NaF) included in different products such as gel, varnish and toothpaste [<xref ref-type="bibr" rid="ref1">1</xref>,<xref ref-type="bibr" rid="ref2">2</xref>]. However, varnish has some advantages over the other products, since it adheres to the tooth surface allowing for a long time of contact between the fluoride and teeth. It also presents low systemic toxicity, and is well tolerated and accepted by patients, especially children [<xref ref-type="bibr" rid="ref1">1</xref>,<xref ref-type="bibr" rid="ref2">2</xref>,<xref ref-type="bibr" rid="ref21">21</xref>]. Therefore, we tested the anticaries effect of an experimental TiF<sub>4</sub> varnish.</p>
      <p>Incorporating TiF<sub>4</sub> into a varnish allows for a longer contact time with enamel, thereby improving the reaction of titanium with the tooth apatite and facilitating the formation of a glaze-like layer on the tooth surface that is rich in titanium dioxide, hydrated titanium phosphate and CaF<sub>2</sub>[<xref ref-type="bibr" rid="ref6">6</xref>,<xref ref-type="bibr" rid="ref10">10</xref>]. Due to its low pH, a TiF<sub>4</sub> varnish is able to enhance the enamel fluoride uptake compared to a NaF varnish [<xref ref-type="bibr" rid="ref10">10</xref>]. The varnish may also reduce TiF<sub>4</sub> contact with soft tissues compared to a rinse solution, reducing the possibility of cytotoxicity due to its low pH [<xref ref-type="bibr" rid="ref22">22</xref>]. A recent study has shown that a TiF<sub>4</sub> varnish presents similar levels of toxicity to murine fibroblast lineage (NIH/3T3) cells as a NaF varnish [<xref ref-type="bibr" rid="ref22">22</xref>]. To check for possible side effects of the TiF<sub>4</sub> varnish, patient satisfaction was evaluated using a simple, but effective tool for self-rated child pain [<xref ref-type="bibr" rid="ref18">18</xref>].</p>
      <p>Previous studies have shown that the application of fluoride varnish once a week for 4 consecutive weeks (4 applications in a one-month interval) has been effective in accelerating remineralization of white spot lesions [<xref ref-type="bibr" rid="ref16">16</xref>]. On the other hand, biannual applications are effective for the prevention of new carious lesions [<xref ref-type="bibr" rid="ref17">17</xref>,<xref ref-type="bibr" rid="ref21">21</xref>]. The focus of the research is preventing and treating carious lesions on smooth tooth surfaces, which is where fluoride varnish is predominantly used [<xref ref-type="bibr" rid="ref1">1</xref>]. For occlusal surfaces, other treatments are often indicated, such as fissure sealants, despite a recent systematic review has demonstrated positive results using NaF varnish on occlusal surfaces [<xref ref-type="bibr" rid="ref23">23</xref>].</p>
      <p>The most common method for detecting caries is the visual-tactile technique by using the ICDAS, Nyvad and DMFT indexes. However, other noninvasive techniques for the detection of early carious lesions have been developed, such as QLF and DIAGNOdent, which are especially used for research purposes [<xref ref-type="bibr" rid="ref24">24</xref>]. The traditional DMFT index is based on detecting carious lesions at the cavitated level only, but it is not a good method for identifying these lesions at a very early stage [<xref ref-type="bibr" rid="ref25">25</xref>]. On the other hand, ICDAS is an accurate and reproducible method for discovering early lesions in enamel and also for detecting changes over time [<xref ref-type="bibr" rid="ref24">24</xref>]. Braga et al [<xref ref-type="bibr" rid="ref26">26</xref>] compared two methods of visual inspection (ie, Nyvad and ICDAS), and both presented good reproducibility and validity in regards to identify and estimate lesion depth, which justifies their inclusion in the present study.</p>
      <p>The QLF is a sensible quantitative clinical method with good repeatability and reproducibility, requiring a smaller number of participants (that may decrease the impact of dropout for longitudinal studies) compared to the visual analysis [<xref ref-type="bibr" rid="ref14">14</xref>]. The QLF is able to quantify small mineral changes that might not be detectable in the visual inspection. However, the method is not reliable for detecting the portion of the subsurface lesion where minerals are gained or lost [<xref ref-type="bibr" rid="ref14">14</xref>,<xref ref-type="bibr" rid="ref20">20</xref>]. Therefore, we combined the visual inspection with a complementary method (QLF) to better detect and quantify carious lesions at a very early stage [<xref ref-type="bibr" rid="ref24">24</xref>].</p>
      <p>Despite our hypothesis on the effectiveness of the TiF<sub>4</sub> varnish, results obtained at the first month of this study demonstrate that the differences between TiF<sub>4</sub> and NaF did not reach significance, due to the slight changes in the visual analysis and in the fluorescence loss. If the TiF<sub>4</sub> varnish proves to be better at controlling dental caries compared to the NaF version by the end of our study, it shall be marketed and distributed at the individual level and to community programs, in order to prevent and treat dental carious lesions in children in the future.</p>
    </sec>
  </body>
  <back>
    <glossary>
      <title>Abbreviations</title>
      <def-list>
        <def-item>
          <term id="abb1">CaF<sub>2</sub></term>
          <def>
            <p>calcium fluoride</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb2">CCD</term>
          <def>
            <p>charged coupled device</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb3">CNPq</term>
          <def>
            <p>National Council for Scientific and Technological Development</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb4">DMFT</term>
          <def>
            <p>decayed, missing, filled teeth index</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb5">DIAGNOdent</term>
          <def>
            <p>Brazilian device used for measuring teeth demineralization in vivo.</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb6">EMEF</term>
          <def>
            <p>municipal school of fundamental education</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb7">F</term>
          <def>
            <p>fluoride</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb8">FAPESP</term>
          <def>
            <p>The São Paulo State Research Foundation</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb9">ICDAS</term>
          <def>
            <p>International Caries Detection and Assessment System</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb10">MFP</term>
          <def>
            <p>monofluoride phosphate</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb11">NaF</term>
          <def>
            <p>sodium fluoride</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb12">NIH/3T3</term>
          <def>
            <p>murine fibroblast lineage</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb13">QLF</term>
          <def>
            <p>quantitative light-induced fluorescence</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb14">SnF<sub>2</sub></term>
          <def>
            <p>stannous fluoride</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb15">TiF<sub>4</sub></term>
          <def>
            <p>titanium tetrafluoride</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb16">WBPS</term>
          <def>
            <p>Wong-Baker Pain Scale</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb17">WS</term>
          <def>
            <p>white spot area</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb18">ΔF</term>
          <def>
            <p>mean fluorescence loss</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb19">ΔWS</term>
          <def>
            <p>variation of the white spot lesion area</p>
          </def>
        </def-item>
        <def-item>
          <term id="abb20">ΔΔF</term>
          <def>
            <p>variation of the mean fluorescence loss</p>
          </def>
        </def-item>
      </def-list>
    </glossary>
    <ack>
      <p>This study is funded by the São Paulo State Research Foundation (FAPESP-2015/14149-1) and the National Council for Scientific and Technological Development (CNPq-401313/2016-6).</p>
    </ack>
    <fn-group>
      <fn fn-type="conflict">
        <p>None declared.</p>
      </fn>
    </fn-group>
    <ref-list>
      <ref id="ref1">
        <label>1</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Gao</surname>
            <given-names>SS</given-names>
          </name>
          <name name-style="western">
            <surname>Zhang</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Mei</surname>
            <given-names>ML</given-names>
          </name>
          <name name-style="western">
            <surname>Lo</surname>
            <given-names>EC</given-names>
          </name>
          <name name-style="western">
            <surname>Chu</surname>
            <given-names>C</given-names>
          </name>
        </person-group>
        <article-title>Caries remineralisation and arresting effect in children by professionally applied fluoride treatment - a systematic review</article-title>
        <source>BMC Oral Health</source>  
        <year>2016</year>  
        <month>02</month>  
        <day>01</day>  
        <volume>16</volume>  
        <fpage>12</fpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://bmcoralhealth.biomedcentral.com/articles/10.1186/s12903-016-0171-6"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1186/s12903-016-0171-6</pub-id>
        <pub-id pub-id-type="medline">26831727</pub-id>
        <pub-id pub-id-type="pii">10.1186/s12903-016-0171-6</pub-id>
        <pub-id pub-id-type="pmcid">PMC4736084</pub-id></nlm-citation>
      </ref>
      <ref id="ref2">
        <label>2</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Marinho</surname>
            <given-names>VCC</given-names>
          </name>
          <name name-style="western">
            <surname>Worthington</surname>
            <given-names>HV</given-names>
          </name>
          <name name-style="western">
            <surname>Walsh</surname>
            <given-names>T</given-names>
          </name>
          <name name-style="western">
            <surname>Clarkson</surname>
            <given-names>JE</given-names>
          </name>
        </person-group>
        <article-title>Fluoride varnishes for preventing dental caries in children and adolescents</article-title>
        <source>Cochrane Database Syst Rev</source>  
        <year>2013</year>  
        <month>07</month>  
        <day>11</day>  
        <issue>7</issue>  
        <fpage>CD002279</fpage>  
        <pub-id pub-id-type="doi">10.1002/14651858.CD002279.pub2</pub-id>
        <pub-id pub-id-type="medline">23846772</pub-id></nlm-citation>
      </ref>
      <ref id="ref3">
        <label>3</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Douglas</surname>
            <given-names>GVA</given-names>
          </name>
          <name name-style="western">
            <surname>Ramsdale</surname>
            <given-names>MP</given-names>
          </name>
          <name name-style="western">
            <surname>Vinall-Collier</surname>
            <given-names>K</given-names>
          </name>
          <name name-style="western">
            <surname>Csikar</surname>
            <given-names>JI</given-names>
          </name>
        </person-group>
        <article-title>Using High Fluoride Concentration Products in Public Policy: A Rapid Review of Current Guidelines for High Fluoride Concentration Products</article-title>
        <source>Caries Res</source>  
        <year>2016</year>  
        <volume>50 Suppl 1</volume>  
        <fpage>50</fpage>  
        <lpage>60</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://www.karger.com?DOI=10.1159/000443409"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1159/000443409</pub-id>
        <pub-id pub-id-type="medline">27100106</pub-id>
        <pub-id pub-id-type="pii">000443409</pub-id></nlm-citation>
      </ref>
      <ref id="ref4">
        <label>4</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Tellez</surname>
            <given-names>M</given-names>
          </name>
          <name name-style="western">
            <surname>Wolff</surname>
            <given-names>MS</given-names>
          </name>
        </person-group>
        <article-title>The Public Health Reach of High Fluoride Vehicles: Examples of Innovative Approaches</article-title>
        <source>Caries Res</source>  
        <year>2016</year>  
        <volume>50 Suppl 1</volume>  
        <fpage>61</fpage>  
        <lpage>7</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://www.karger.com?DOI=10.1159/000443186"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1159/000443186</pub-id>
        <pub-id pub-id-type="medline">27099929</pub-id>
        <pub-id pub-id-type="pii">000443186</pub-id></nlm-citation>
      </ref>
      <ref id="ref5">
        <label>5</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Ardenghi</surname>
            <given-names>TM</given-names>
          </name>
          <name name-style="western">
            <surname>Piovesan</surname>
            <given-names>C</given-names>
          </name>
          <name name-style="western">
            <surname>Antunes</surname>
            <given-names>JLF</given-names>
          </name>
        </person-group>
        <article-title>[Inequalities in untreated dental caries prevalence in preschool children in Brazil]</article-title>
        <source>Rev Saude Publica</source>  
        <year>2013</year>  
        <month>12</month>  
        <volume>47 Suppl 3</volume>  
        <fpage>129</fpage>  
        <lpage>37</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.scielo.br/scielo.php?script=sci_arttext&#38;pid=S0034-89102013000800129&#38;lng=en&#38;nrm=iso&#38;tlng=en"/>
        </comment>  
        <pub-id pub-id-type="medline">24626589</pub-id>
        <pub-id pub-id-type="pii">S0034-89102013000800129</pub-id></nlm-citation>
      </ref>
      <ref id="ref6">
        <label>6</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Wiegand</surname>
            <given-names>A</given-names>
          </name>
          <name name-style="western">
            <surname>Magalhães</surname>
            <given-names>AC</given-names>
          </name>
          <name name-style="western">
            <surname>Attin</surname>
            <given-names>T</given-names>
          </name>
        </person-group>
        <article-title>Is titanium tetrafluoride (TiF<sub>4</sub>) effective to prevent carious and erosive lesions? A review of the literature</article-title>
        <source>Oral Health Prev Dent</source>  
        <year>2010</year>  
        <volume>8</volume>  
        <issue>2</issue>  
        <fpage>159</fpage>  
        <lpage>64</lpage>  
        <pub-id pub-id-type="medline">20589250</pub-id>
        <pub-id pub-id-type="pii">19210</pub-id></nlm-citation>
      </ref>
      <ref id="ref7">
        <label>7</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Comar</surname>
            <given-names>LP</given-names>
          </name>
          <name name-style="western">
            <surname>Souza</surname>
            <given-names>BM</given-names>
          </name>
          <name name-style="western">
            <surname>Martins</surname>
            <given-names>J</given-names>
          </name>
          <name name-style="western">
            <surname>Santos</surname>
            <given-names>MG</given-names>
          </name>
          <name name-style="western">
            <surname>Buzalaf</surname>
            <given-names>MAR</given-names>
          </name>
          <name name-style="western">
            <surname>Magalhães</surname>
            <given-names>AC</given-names>
          </name>
        </person-group>
        <article-title>Response of carious enamel to TiF<sub>4</sub> varnish treatment under diverse cariogenic activities in situ</article-title>
        <source>J Dent</source>  
        <year>2017</year>  
        <month>08</month>  
        <volume>63</volume>  
        <fpage>81</fpage>  
        <lpage>4</lpage>  
        <pub-id pub-id-type="doi">10.1016/j.jdent.2017.05.023</pub-id>
        <pub-id pub-id-type="medline">28579385</pub-id>
        <pub-id pub-id-type="pii">S0300-5712(17)30133-1</pub-id></nlm-citation>
      </ref>
      <ref id="ref8">
        <label>8</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Magalhães</surname>
            <given-names>AC</given-names>
          </name>
          <name name-style="western">
            <surname>Comar</surname>
            <given-names>LP</given-names>
          </name>
          <name name-style="western">
            <surname>Rios</surname>
            <given-names>D</given-names>
          </name>
          <name name-style="western">
            <surname>Delbem</surname>
            <given-names>ACB</given-names>
          </name>
          <name name-style="western">
            <surname>Buzalaf</surname>
            <given-names>MAR</given-names>
          </name>
        </person-group>
        <article-title>Effect of a 4% titanium tetrafluoride (TiF<sub>4</sub>) varnish on demineralisation and remineralisation of bovine enamel in vitro</article-title>
        <source>J Dent</source>  
        <year>2008</year>  
        <month>02</month>  
        <volume>36</volume>  
        <issue>2</issue>  
        <fpage>158</fpage>  
        <lpage>62</lpage>  
        <pub-id pub-id-type="doi">10.1016/j.jdent.2007.12.001</pub-id>
        <pub-id pub-id-type="medline">18187248</pub-id>
        <pub-id pub-id-type="pii">S0300-5712(07)00249-7</pub-id></nlm-citation>
      </ref>
      <ref id="ref9">
        <label>9</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Comar</surname>
            <given-names>LP</given-names>
          </name>
          <name name-style="western">
            <surname>Wiegand</surname>
            <given-names>A</given-names>
          </name>
          <name name-style="western">
            <surname>Moron</surname>
            <given-names>BM</given-names>
          </name>
          <name name-style="western">
            <surname>Rios</surname>
            <given-names>D</given-names>
          </name>
          <name name-style="western">
            <surname>Buzalaf</surname>
            <given-names>MAR</given-names>
          </name>
          <name name-style="western">
            <surname>Buchalla</surname>
            <given-names>W</given-names>
          </name>
          <name name-style="western">
            <surname>Magalhães</surname>
            <given-names>Ana C</given-names>
          </name>
        </person-group>
        <article-title>In situ effect of sodium fluoride or titanium tetrafluoride varnish and solution on carious demineralization of enamel</article-title>
        <source>Eur J Oral Sci</source>  
        <year>2012</year>  
        <month>08</month>  
        <volume>120</volume>  
        <issue>4</issue>  
        <fpage>342</fpage>  
        <lpage>8</lpage>  
        <pub-id pub-id-type="doi">10.1111/j.1600-0722.2012.00968.x</pub-id>
        <pub-id pub-id-type="medline">22813225</pub-id></nlm-citation>
      </ref>
      <ref id="ref10">
        <label>10</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Comar</surname>
            <given-names>LP</given-names>
          </name>
          <name name-style="western">
            <surname>Souza</surname>
            <given-names>BM</given-names>
          </name>
          <name name-style="western">
            <surname>Al-Ahj</surname>
            <given-names>LP</given-names>
          </name>
          <name name-style="western">
            <surname>Martins</surname>
            <given-names>J</given-names>
          </name>
          <name name-style="western">
            <surname>Grizzo</surname>
            <given-names>LT</given-names>
          </name>
          <name name-style="western">
            <surname>Piasentim</surname>
            <given-names>IS</given-names>
          </name>
          <name name-style="western">
            <surname>Rios</surname>
            <given-names>D</given-names>
          </name>
          <name name-style="western">
            <surname>Buzalaf</surname>
            <given-names>MAR</given-names>
          </name>
          <name name-style="western">
            <surname>Magalhães</surname>
            <given-names>AC</given-names>
          </name>
        </person-group>
        <article-title>Mechanism of Action of TiF<sub>4</sub> on Dental Enamel Surface: SEM/EDX, KOH-Soluble F, and X-Ray Diffraction Analysis</article-title>
        <source>Caries Res</source>  
        <year>2017</year>  
        <month>10</month>  
        <day>12</day>  
        <volume>51</volume>  
        <issue>6</issue>  
        <fpage>554</fpage>  
        <lpage>67</lpage>  
        <pub-id pub-id-type="doi">10.1159/000479038</pub-id>
        <pub-id pub-id-type="medline">29020673</pub-id>
        <pub-id pub-id-type="pii">000479038</pub-id></nlm-citation>
      </ref>
      <ref id="ref11">
        <label>11</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Weintraub</surname>
            <given-names>JA</given-names>
          </name>
          <name name-style="western">
            <surname>Ramos-Gomez</surname>
            <given-names>F</given-names>
          </name>
          <name name-style="western">
            <surname>Jue</surname>
            <given-names>B</given-names>
          </name>
          <name name-style="western">
            <surname>Shain</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Hoover</surname>
            <given-names>CI</given-names>
          </name>
          <name name-style="western">
            <surname>Featherstone</surname>
            <given-names>JDB</given-names>
          </name>
          <name name-style="western">
            <surname>Gansky</surname>
            <given-names>SA</given-names>
          </name>
        </person-group>
        <article-title>Fluoride varnish efficacy in preventing early childhood caries</article-title>
        <source>J Dent Res</source>  
        <year>2006</year>  
        <month>02</month>  
        <volume>85</volume>  
        <issue>2</issue>  
        <fpage>172</fpage>  
        <lpage>6</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://europepmc.org/abstract/MED/16434737"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1177/154405910608500211</pub-id>
        <pub-id pub-id-type="medline">16434737</pub-id>
        <pub-id pub-id-type="pii">85/2/172</pub-id>
        <pub-id pub-id-type="pmcid">PMC2257982</pub-id></nlm-citation>
      </ref>
      <ref id="ref12">
        <label>12</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Nyvad</surname>
            <given-names>B</given-names>
          </name>
          <name name-style="western">
            <surname>Machiulskiene</surname>
            <given-names>V</given-names>
          </name>
          <name name-style="western">
            <surname>Baelum</surname>
            <given-names>V</given-names>
          </name>
        </person-group>
        <article-title>Construct and predictive validity of clinical caries diagnostic criteria assessing lesion activity</article-title>
        <source>J Dent Res</source>  
        <year>2003</year>  
        <month>02</month>  
        <volume>82</volume>  
        <issue>2</issue>  
        <fpage>117</fpage>  
        <lpage>22</lpage>  
        <pub-id pub-id-type="doi">10.1177/154405910308200208</pub-id>
        <pub-id pub-id-type="medline">12562884</pub-id></nlm-citation>
      </ref>
      <ref id="ref13">
        <label>13</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Zero</surname>
            <given-names>DT</given-names>
          </name>
        </person-group>
        <article-title>Dental caries process</article-title>
        <source>Dent Clin North Am</source>  
        <year>1999</year>  
        <month>10</month>  
        <volume>43</volume>  
        <issue>4</issue>  
        <fpage>635</fpage>  
        <lpage>64</lpage>  
        <pub-id pub-id-type="medline">10553248</pub-id></nlm-citation>
      </ref>
      <ref id="ref14">
        <label>14</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Tranaeus</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Al-Khateeb</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Björkman</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Twetman</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Angmar-Månsson</surname>
            <given-names>B</given-names>
          </name>
        </person-group>
        <article-title>Application of quantitative light-induced fluorescence to monitor incipient lesions in caries-active children. A comparative study of remineralisation by fluoride varnish and professional cleaning</article-title>
        <source>Eur J Oral Sci</source>  
        <year>2001</year>  
        <month>04</month>  
        <volume>109</volume>  
        <issue>2</issue>  
        <fpage>71</fpage>  
        <lpage>5</lpage>  
        <pub-id pub-id-type="medline">11347658</pub-id></nlm-citation>
      </ref>
      <ref id="ref15">
        <label>15</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Shivakumar</surname>
            <given-names>K</given-names>
          </name>
          <name name-style="western">
            <surname>Prasad</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Chandu</surname>
            <given-names>G</given-names>
          </name>
        </person-group>
        <article-title>International Caries Detection and Assessment System: A new paradigm in detection of dental caries</article-title>
        <source>J Conserv Dent</source>  
        <year>2009</year>  
        <month>01</month>  
        <volume>12</volume>  
        <issue>1</issue>  
        <fpage>10</fpage>  
        <lpage>6</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.jcd.org.in/article.asp?issn=0972-0707;year=2009;volume=12;issue=1;spage=10;epage=16;aulast=Shivakumar"/>
        </comment>  
        <pub-id pub-id-type="doi">10.4103/0972-0707.53335</pub-id>
        <pub-id pub-id-type="medline">20379434</pub-id>
        <pub-id pub-id-type="pmcid">PMC2848805</pub-id></nlm-citation>
      </ref>
      <ref id="ref16">
        <label>16</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Almeida</surname>
            <given-names>MQD</given-names>
          </name>
          <name name-style="western">
            <surname>Costa</surname>
            <given-names>OXI</given-names>
          </name>
          <name name-style="western">
            <surname>Ferreira</surname>
            <given-names>JMS</given-names>
          </name>
          <name name-style="western">
            <surname>Menezes</surname>
            <given-names>VAD</given-names>
          </name>
          <name name-style="western">
            <surname>Leal</surname>
            <given-names>RB</given-names>
          </name>
          <name name-style="western">
            <surname>Sampaio</surname>
            <given-names>FC</given-names>
          </name>
        </person-group>
        <article-title>Therapeutic potential of Brazilian fluoride varnishes: an in vivo study</article-title>
        <source>Braz Dent J</source>  
        <year>2011</year>  
        <volume>22</volume>  
        <issue>3</issue>  
        <fpage>193</fpage>  
        <lpage>7</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.scielo.br/scielo.php?script=sci_arttext&#38;pid=S0103-64402011000300003&#38;lng=en&#38;nrm=iso&#38;tlng=en"/>
        </comment>  
        <pub-id pub-id-type="medline">21915515</pub-id>
        <pub-id pub-id-type="pii">S0103-64402011000300003</pub-id></nlm-citation>
      </ref>
      <ref id="ref17">
        <label>17</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Hedman</surname>
            <given-names>E</given-names>
          </name>
          <name name-style="western">
            <surname>Gabre</surname>
            <given-names>P</given-names>
          </name>
          <name name-style="western">
            <surname>Birkhed</surname>
            <given-names>D</given-names>
          </name>
        </person-group>
        <article-title>Dental hygienists working in schools - a two-year oral health intervention programme in swedish secondary schools</article-title>
        <source>Oral Health Prev Dent</source>  
        <year>2015</year>  
        <volume>13</volume>  
        <issue>2</issue>  
        <fpage>177</fpage>  
        <lpage>88</lpage>  
        <pub-id pub-id-type="doi">10.3290/j.ohpd.a32132</pub-id>
        <pub-id pub-id-type="medline">24914429</pub-id>
        <pub-id pub-id-type="pii">32132</pub-id></nlm-citation>
      </ref>
      <ref id="ref18">
        <label>18</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>El</surname>
            <given-names>BHY</given-names>
          </name>
        </person-group>
        <article-title>Effect of intraoperative analgesia on children's pain perception during recovery after painful dental procedures performed under general anaesthesia</article-title>
        <source>Eur Arch Paediatr Dent</source>  
        <year>2015</year>  
        <month>02</month>  
        <volume>16</volume>  
        <issue>1</issue>  
        <fpage>35</fpage>  
        <lpage>41</lpage>  
        <pub-id pub-id-type="doi">10.1007/s40368-014-0143-y</pub-id>
        <pub-id pub-id-type="medline">25260983</pub-id></nlm-citation>
      </ref>
      <ref id="ref19">
        <label>19</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Nyvad</surname>
            <given-names>B</given-names>
          </name>
          <name name-style="western">
            <surname>Machiulskiene</surname>
            <given-names>V</given-names>
          </name>
          <name name-style="western">
            <surname>Baelum</surname>
            <given-names>V</given-names>
          </name>
        </person-group>
        <article-title>Reliability of a new caries diagnostic system differentiating between active and inactive caries lesions</article-title>
        <source>Caries Res</source>  
        <year>1999</year>  
        <volume>33</volume>  
        <issue>4</issue>  
        <fpage>252</fpage>  
        <lpage>60</lpage>  
        <pub-id pub-id-type="doi">10.1159/000016526</pub-id>
        <pub-id pub-id-type="medline">10343087</pub-id>
        <pub-id pub-id-type="pii">16526</pub-id></nlm-citation>
      </ref>
      <ref id="ref20">
        <label>20</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Sitthisettapong</surname>
            <given-names>Thanya</given-names>
          </name>
          <name name-style="western">
            <surname>Doi</surname>
            <given-names>Takashi</given-names>
          </name>
          <name name-style="western">
            <surname>Nishida</surname>
            <given-names>Yuhei</given-names>
          </name>
          <name name-style="western">
            <surname>Kambara</surname>
            <given-names>Masaki</given-names>
          </name>
          <name name-style="western">
            <surname>Phantumvanit</surname>
            <given-names>Prathip</given-names>
          </name>
        </person-group>
        <article-title>Effect of CPP-ACP Paste on Enamel Carious Lesion of Primary Upper Anterior Teeth Assessed by Quantitative Light-Induced Fluorescence: A One-Year Clinical Trial</article-title>
        <source>Caries Res</source>  
        <year>2015</year>  
        <month>03</month>  
        <volume>49</volume>  
        <issue>4</issue>  
        <fpage>434</fpage>  
        <lpage>41</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.mdpi.com/resolver?pii=ijerph120303002"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1159/000434728</pub-id>
        <pub-id pub-id-type="medline">26228178</pub-id>
        <pub-id pub-id-type="pii">000434728</pub-id>
        <pub-id pub-id-type="pmcid">PMC4377948</pub-id></nlm-citation>
      </ref>
      <ref id="ref21">
        <label>21</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Divaris</surname>
            <given-names>K</given-names>
          </name>
          <name name-style="western">
            <surname>Preisser</surname>
            <given-names>JS</given-names>
          </name>
          <name name-style="western">
            <surname>Slade</surname>
            <given-names>GD</given-names>
          </name>
        </person-group>
        <article-title>Surface-specific efficacy of fluoride varnish in caries prevention in the primary dentition: results of a community randomized clinical trial</article-title>
        <source>Caries Res</source>  
        <year>2013</year>  
        <volume>47</volume>  
        <issue>1</issue>  
        <fpage>78</fpage>  
        <lpage>87</lpage>  
        <pub-id pub-id-type="doi">10.1159/000344015</pub-id>
        <pub-id pub-id-type="medline">23207237</pub-id>
        <pub-id pub-id-type="pii">000344015</pub-id></nlm-citation>
      </ref>
      <ref id="ref22">
        <label>22</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Salomão</surname>
            <given-names>PMA</given-names>
          </name>
          <name name-style="western">
            <surname>Oliveira</surname>
            <given-names>FAD</given-names>
          </name>
          <name name-style="western">
            <surname>Rodrigues</surname>
            <given-names>PD</given-names>
          </name>
          <name name-style="western">
            <surname>Al-Ahj</surname>
            <given-names>LP</given-names>
          </name>
          <name name-style="western">
            <surname>Gasque</surname>
            <given-names>KCDS</given-names>
          </name>
          <name name-style="western">
            <surname>Jeggle</surname>
            <given-names>P</given-names>
          </name>
          <name name-style="western">
            <surname>Buzalaf</surname>
            <given-names>MAR</given-names>
          </name>
          <name name-style="western">
            <surname>Oliveira</surname>
            <given-names>RCD</given-names>
          </name>
          <name name-style="western">
            <surname>Edwardson</surname>
            <given-names>JM</given-names>
          </name>
          <name name-style="western">
            <surname>Magalhães</surname>
            <given-names>AC</given-names>
          </name>
        </person-group>
        <article-title>The cytotoxic effect of TiF<sub>4</sub> and NaF on fibroblasts is influenced by the experimental model, fluoride concentration and exposure time</article-title>
        <source>PLoS One</source>  
        <year>2017</year>  
        <volume>12</volume>  
        <issue>6</issue>  
        <fpage>e0179471</fpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://dx.plos.org/10.1371/journal.pone.0179471"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1371/journal.pone.0179471</pub-id>
        <pub-id pub-id-type="medline">28614381</pub-id>
        <pub-id pub-id-type="pii">PONE-D-17-00728</pub-id>
        <pub-id pub-id-type="pmcid">PMC5470716</pub-id></nlm-citation>
      </ref>
      <ref id="ref23">
        <label>23</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Ahovuo-Saloranta</surname>
            <given-names>A</given-names>
          </name>
          <name name-style="western">
            <surname>Forss</surname>
            <given-names>H</given-names>
          </name>
          <name name-style="western">
            <surname>Hiiri</surname>
            <given-names>A</given-names>
          </name>
          <name name-style="western">
            <surname>Nordblad</surname>
            <given-names>A</given-names>
          </name>
          <name name-style="western">
            <surname>Mäkelä</surname>
            <given-names>M</given-names>
          </name>
        </person-group>
        <article-title>Pit and fissure sealants versus fluoride varnishes for preventing dental decay in the permanent teeth of children and adolescents</article-title>
        <source>Cochrane Database Syst Rev</source>  
        <year>2016</year>  
        <month>01</month>  
        <day>18</day>  
        <issue>1</issue>  
        <fpage>CD003067</fpage>  
        <pub-id pub-id-type="doi">10.1002/14651858.CD003067.pub4</pub-id>
        <pub-id pub-id-type="medline">26780162</pub-id></nlm-citation>
      </ref>
      <ref id="ref24">
        <label>24</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Gomez</surname>
            <given-names>J</given-names>
          </name>
        </person-group>
        <article-title>Detection and diagnosis of the early caries lesion</article-title>
        <source>BMC Oral Health</source>  
        <year>2015</year>  
        <volume>15 Suppl 1</volume>  
        <fpage>S3</fpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="https://bmcoralhealth.biomedcentral.com/articles/10.1186/1472-6831-15-S1-S3"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1186/1472-6831-15-S1-S3</pub-id>
        <pub-id pub-id-type="medline">26392124</pub-id>
        <pub-id pub-id-type="pii">1472-6831-15-S1-S3</pub-id>
        <pub-id pub-id-type="pmcid">PMC4580848</pub-id></nlm-citation>
      </ref>
      <ref id="ref25">
        <label>25</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Melgar</surname>
            <given-names>RA</given-names>
          </name>
          <name name-style="western">
            <surname>Pereira</surname>
            <given-names>JT</given-names>
          </name>
          <name name-style="western">
            <surname>Luz</surname>
            <given-names>PB</given-names>
          </name>
          <name name-style="western">
            <surname>Hugo</surname>
            <given-names>FN</given-names>
          </name>
          <name name-style="western">
            <surname>Araujo</surname>
            <given-names>FBD</given-names>
          </name>
        </person-group>
        <article-title>Differential Impacts of Caries Classification in Children and Adults: A Comparison of ICDAS and DMF-T</article-title>
        <source>Braz Dent J</source>  
        <year>2016</year>  
        <volume>27</volume>  
        <issue>6</issue>  
        <fpage>761</fpage>  
        <lpage>6</lpage>  
        <comment>
          <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" xlink:href="http://www.scielo.br/scielo.php?script=sci_arttext&#38;pid=S0103-64402016000600761&#38;lng=en&#38;nrm=iso&#38;tlng=en"/>
        </comment>  
        <pub-id pub-id-type="doi">10.1590/0103-6440201600990</pub-id>
        <pub-id pub-id-type="medline">27982192</pub-id>
        <pub-id pub-id-type="pii">S0103-64402016000600761</pub-id></nlm-citation>
      </ref>
      <ref id="ref26">
        <label>26</label>
        <nlm-citation citation-type="journal">
        <person-group person-group-type="author">
          <name name-style="western">
            <surname>Braga</surname>
            <given-names>MM</given-names>
          </name>
          <name name-style="western">
            <surname>Ekstrand</surname>
            <given-names>KR</given-names>
          </name>
          <name name-style="western">
            <surname>Martignon</surname>
            <given-names>S</given-names>
          </name>
          <name name-style="western">
            <surname>Imparato</surname>
            <given-names>JCP</given-names>
          </name>
          <name name-style="western">
            <surname>Ricketts</surname>
            <given-names>DNJ</given-names>
          </name>
          <name name-style="western">
            <surname>Mendes</surname>
            <given-names>FM</given-names>
          </name>
        </person-group>
        <article-title>Clinical performance of two visual scoring systems in detecting and assessing activity status of occlusal caries in primary teeth</article-title>
        <source>Caries Res</source>  
        <year>2010</year>  
        <volume>44</volume>  
        <issue>3</issue>  
        <fpage>300</fpage>  
        <lpage>8</lpage>  
        <pub-id pub-id-type="doi">10.1159/000315616</pub-id>
        <pub-id pub-id-type="medline">20530964</pub-id>
        <pub-id pub-id-type="pii">000315616</pub-id></nlm-citation>
      </ref>
    </ref-list>
  </back>
</article>
