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<article article-type="research-article" dtd-version="1.0" xml:lang="en" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">JKAOH</journal-id>
<journal-title-group>
<journal-title>Journal of Korean Academy of Oral Health</journal-title>
<abbrev-journal-title>J Korean Acad Oral Health</abbrev-journal-title>
</journal-title-group>
<issn pub-type="ppub">1225-388X</issn>
<issn pub-type="epub">2093-7784</issn>
<publisher>
<publisher-name>Journal of Korean Academy of Oral Health</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.11149/jkaoh.2018.42.1.3</article-id>
<article-id pub-id-type="publisher-id">jkaoh-42-3</article-id>
<article-categories>
<subj-group>
<subject>Original Article</subject>
</subj-group>
</article-categories>
<title-group>
<article-title>School loss days due to dental diseases among adolescents</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author"><name name-style="western" xml:lang="en"><surname>Park</surname><given-names>Sang-Su</given-names></name><xref ref-type="aff" rid="aff1-jkaoh-42-3"/></contrib>
<contrib contrib-type="author"><name name-style="western" xml:lang="en"><surname>Kim</surname><given-names>In-Ja</given-names></name><xref ref-type="aff" rid="aff1-jkaoh-42-3"/></contrib>
<contrib contrib-type="author"><name name-style="western" xml:lang="en"><surname>Ju</surname><given-names>Hyun-Jeong</given-names></name><xref ref-type="aff" rid="aff1-jkaoh-42-3"/></contrib>
<contrib contrib-type="author"><name name-style="western" xml:lang="en"><surname>Lee</surname><given-names>Sun-Ho</given-names></name><xref ref-type="aff" rid="aff1-jkaoh-42-3"/></contrib>
<contrib contrib-type="author"><name name-style="western" xml:lang="en"><surname>Oh</surname><given-names>Hyo-Won</given-names></name><xref ref-type="aff" rid="aff1-jkaoh-42-3"/></contrib>
<contrib contrib-type="author"><name name-style="western" xml:lang="en"><surname>Lee</surname><given-names>Heung-Soo</given-names></name><xref ref-type="aff" rid="aff1-jkaoh-42-3"/>
<xref ref-type="corresp" rid="c1-jkaoh-42-3"/></contrib>
<aff id="aff1-jkaoh-42-3" xml:lang="en">Department of Preventive and Public Health Dentistry, College of Dentistry, Wonkwang University, Iksan, <country>Korea</country></aff>
</contrib-group>
<author-notes>
<corresp id="c1-jkaoh-42-3">Corresponding Author: Heung-Soo Lee Department of Preventive and Public Health Dentistry, College of Dentistry, Wonkwang University, 460 Iksan-daero, Iksan 54538, Korea Tel: +82-63-850-6851 Fax: +82-63-857-4837 E-mail: <email>smagn@wonkwang.ac.kr</email></corresp>
</author-notes>
<pub-date pub-type="ppub"><month>03</month><year>2018</year></pub-date>
<pub-date pub-type="epub"><day>15</day><month>03</month><year>2018</year></pub-date>
<volume>42</volume><issue>1</issue>
<fpage>3</fpage><lpage>8</lpage>
<history>
<date date-type="received"><day>08</day><month>01</month><year>2018</year></date>
<date date-type="rev-recd"><day>08</day><month>03</month><year>2018</year></date>
<date date-type="accepted"><day>15</day><month>03</month><year>2018</year></date>
</history>
<permissions>
<copyright-statement>Copyright &#x00A9; 2018 by Journal of Korean Academy of Oral Health</copyright-statement>
<copyright-year>2018</copyright-year>
<license><license-p>This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (<ext-link ext-link-type="uri" xlink:href="http://creativecommons.org/licenses/by-nc/4.0/">http://creativecommons.org/licenses/by-nc/4.0/</ext-link>), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p></license>
</permissions>
<abstract xml:lang="en">
<title>Abstract</title>
<sec>
<title>Objectives</title>
<p>This study aimed to investigate the lost school days due to dental diseases among adolescents and to assess their oral health in relation to their socio-demographic characteristics.</p>
</sec>
<sec>
<title>Methods</title>
<p>A total of 881 adolescents (middle school: 453, high school: 428) were surveyed using a self-administered questionnaire. The questionnaire was composed of questions relating to the subject&#x0027;s socio-demographic characteristics and lost school days due to dental diseases. The lost school days due to dental diseases included absence and early leave. The differences in the lost school days by socio-demographic characteristics were analyzed by chi-square test and t-test.</p>
</sec>
<sec>
<title>Results</title>
<p>In the past year, 2% of adolescents were absent from school (approximately 2 days of absence), 7.6% left school early (about 3 days of early leave), and 8.3% were absent from school or left school early (about 4 days of absence and early leave) because of dental diseases. The most common reason for absence from school was dental caries (31.8%), followed by malocclusion (9.3%), periodontal disease (7%), and maxillofacial trauma (2.3%). Dental caries was the most common reason (18%) for early leave, followed by malocclusion (8.8%), maxillofacial trauma (2.6%), and periodontal disease (1.8%). Absence from school was higher when the educational background of the respondent&#x0027;s father was middle-school graduate or lower (5.6%: middle-school graduates or lower, 1.6%: high-school graduates, 1.8%: college graduates or higher). High school students with dental diseases (11.7%) were absent or went on early leave to a greater extent than middle school students (5.1%).</p>
</sec>
<sec>
<title>Conclusions</title>
<p>To reduce lost school days due to dental diseases among adolescents, different strategies are required including prevention and early treatment of dental caries and avoidance of maxillofacial trauma.</p>
</sec>
</abstract>
<kwd-group xml:lang="en">
<kwd>Adolescents</kwd>
<kwd>Dental caries</kwd>
<kwd>Dental diseases</kwd>
<kwd>Oral health</kwd>
<kwd>School loss</kwd>
</kwd-group>
</article-meta>
</front>
<back>
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<sec sec-type="display-objects">
<title>Tables</title>
<table-wrap id="t1-jkaoh-42-3" position="float">
<label>Table 1.</label>
<caption><p>Demographic characteristics of subjects Unit : N (%)</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th valign="middle" align="center">Characteristics</th>
<th valign="middle" align="center">Classification</th>
<th valign="middle" align="center">N (%)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="left" rowspan="3">School region</td>
<td valign="middle" align="left">City</td>
<td valign="middle" align="center">310 (35.2)</td></tr>
<tr>
<td valign="middle" align="left">Rural area</td>
<td valign="middle" align="center">571 (64.8)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">881 (100.0)</td></tr>
<tr>
<td valign="middle" align="left" rowspan="3">School</td>
<td valign="middle" align="left">Middle school</td>
<td valign="middle" align="center">453 (51.4)</td></tr>
<tr>
<td valign="middle" align="left">High school</td>
<td valign="middle" align="center">428 (48.6)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">881 (100.0)</td></tr>
<tr>
<td valign="middle" align="left" rowspan="3">Sex</td>
<td valign="middle" align="left">Male</td>
<td valign="middle" align="center">427 (48.5)</td></tr>
<tr>
<td valign="middle" align="left">Female</td>
<td valign="middle" align="center">454 (51.5)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">881 (100.0)</td></tr>
<tr>
<td valign="middle" align="left" rowspan="3">Residence</td>
<td valign="middle" align="left">Dong</td>
<td valign="middle" align="center">428 (48.6)</td></tr>
<tr>
<td valign="middle" align="left">Eup/Myeon</td>
<td valign="middle" align="center">453 (51.4)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">881 (100.0)</td></tr>
<tr>
<td valign="middle" align="left" rowspan="4">Father&#x2019;s level of education</td>
<td valign="middle" align="left">&#x2264;Middle school</td>
<td valign="middle" align="center">89 (10.4)</td></tr>
<tr>
<td valign="middle" align="left">High school</td>
<td valign="middle" align="center">432 (50.3)</td></tr>
<tr>
<td valign="middle" align="left">&#x2265;College</td>
<td valign="middle" align="center">338 (39.3)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">859 (100.0)</td></tr>
<tr>
<td valign="middle" align="left" rowspan="4">Mother&#x2019;s level of education</td>
<td valign="middle" align="left">&#x2264;Middle school</td>
<td valign="middle" align="center">79 (9.3)</td></tr>
<tr>
<td valign="middle" align="left">High school</td>
<td valign="middle" align="center">471 (55.7)</td></tr>
<tr>
<td valign="middle" align="left">&#x2265;College</td>
<td valign="middle" align="center">296 (35.0)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">846 (100.0)</td></tr>
<tr>
<td valign="middle" align="left" rowspan="5">Monthly income (Unit : 10,000 won)</td>
<td valign="middle" align="left">&#x2264;200</td>
<td valign="middle" align="center">234 (28.9)</td></tr>
<tr>
<td valign="middle" align="left">200-299</td>
<td valign="middle" align="center">193 (23.8)</td></tr>
<tr>
<td valign="middle" align="left">300-399</td>
<td valign="middle" align="center">166 (20.5)</td></tr>
<tr>
<td valign="middle" align="left">&#x2265;400</td>
<td valign="middle" align="center">217 (26.8)</td></tr>
<tr>
<td valign="middle" align="left">Total</td>
<td valign="middle" align="center">810 (100.0)</td></tr>
</tbody>
</table>
</table-wrap>
<table-wrap id="t2-jkaoh-42-3" position="float">
<label>Table 2.</label>
<caption><p>School loss due to oral disease among adolescents</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th valign="middle" align="center" rowspan="2">Classification</th>
<th valign="middle" align="center" colspan="2">Total<hr/></th>
<th valign="middle" align="center" colspan="2">Middle school student<hr/></th>
<th valign="middle" align="center" colspan="2">High school student<hr/></th>
</tr>
<tr>
<th valign="middle" align="center">Rate</th>
<th valign="middle" align="center">Days (M&#x00B1;SD)</th>
<th valign="middle" align="center">Rate</th>
<th valign="middle" align="center">Days (M&#x00B1;SD)</th>
<th valign="middle" align="center">Rate</th>
<th valign="middle" align="center">Days (M&#x00B1;SD)</th></tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="left">Annual absence from school due to oral disease</td>
<td valign="middle" align="center">2.0%</td>
<td valign="middle" align="center">1.83&#x00B1;1.26</td>
<td valign="middle" align="center">1.5%</td>
<td valign="middle" align="center">1.40&#x00B1;0.89</td>
<td valign="middle" align="center">2.6%</td>
<td valign="middle" align="center">2.14&#x00B1;1.46</td></tr>
<tr>
<td valign="middle" align="left">Annual early leave from school due to oral disease</td>
<td valign="middle" align="center">7.6%</td>
<td valign="middle" align="center">2.96&#x00B1;4.58</td>
<td valign="middle" align="center">4.4*%</td>
<td valign="middle" align="center">3.35&#x00B1;6.99</td>
<td valign="middle" align="center">11.0*%</td>
<td valign="middle" align="center">2.78&#x00B1;3.00</td></tr>
<tr>
<td valign="middle" align="left">Annual absence or early leave from school due to oral disease</td>
<td valign="middle" align="center">8.3%</td>
<td valign="middle" align="center">3.67&#x00B1;2.53</td>
<td valign="middle" align="center">5.1%</td>
<td valign="middle" align="center">2.80&#x00B1;1.78</td>
<td valign="middle" align="center">11.7%</td>
<td valign="middle" align="center">4.16&#x00B1;3.12</td></tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table2-fn1-jkaoh-42-3"><p>*<italic>P</italic>&#x003C;0.05.</p></fn>
</table-wrap-foot>
</table-wrap>
<table-wrap id="t3-jkaoh-42-3" position="float">
<label>Table 3.</label>
<caption><p>Reason of school loss due to oral disease among adolescents* Unit : %<sup><xref ref-type="table-fn" rid="table3-fn2-jkaoh-42-3">&#x2020;</xref></sup></p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th valign="middle" align="center">Classification</th>
<th valign="middle" align="center">Dental caries</th>
<th valign="middle" align="center">Periodontal disease</th>
<th valign="middle" align="center">Malocclusion</th>
<th valign="middle" align="center">Maxillofacial trauma</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="left">Reason of absence from school due to oral disease</td>
<td valign="middle" align="center">12.4%</td>
<td valign="middle" align="center">1.0%</td>
<td valign="middle" align="center">5.0%</td>
<td valign="middle" align="center">1.0%</td></tr>
<tr>
<td valign="middle" align="left">Reason of annual absence from school due to oral disease</td>
<td valign="middle" align="center">31.8%</td>
<td valign="middle" align="center">7.0%</td>
<td valign="middle" align="center">9.3%</td>
<td valign="middle" align="center">2.3%</td></tr>
<tr>
<td valign="middle" align="left">Reason of annual early leave from school due to oral disease</td>
<td valign="middle" align="center">18.0%</td>
<td valign="middle" align="center">1.8%</td>
<td valign="middle" align="center">8.8%</td>
<td valign="middle" align="center">2.6%</td></tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table3-fn1-jkaoh-42-3"><p>*Plural response.</p></fn>
<fn id="table3-fn2-jkaoh-42-3"><label>&#x2020;</label><p>Percentage expressed experience of school loss due to oral disease.</p></fn>
</table-wrap-foot>
</table-wrap>
<table-wrap id="t4-jkaoh-42-3" position="float">
<label>Table 4.</label>
<caption><p>School loss due to oral disease according to demographic characteristics of subjects among adolescents</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th valign="middle" align="center" rowspan="2">Classification</th>
<th valign="middle" align="center" colspan="2">Annual absence<hr/></th>
<th valign="middle" align="center" colspan="2">Annual early leave<hr/></th>
<th valign="middle" align="center" colspan="2">Annual absence or early leave<hr/></th>
</tr>
<tr>
<th valign="middle" align="center">Rate</th>
<th valign="middle" align="center">Days (M&#x00B1;SD)</th>
<th valign="middle" align="center">Rate</th>
<th valign="middle" align="center">Days (M&#x00B1;SD)</th>
<th valign="middle" align="center">Rate</th>
<th valign="middle" align="center">Days (M&#x00B1;SD)</th></tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="left">Sex</td>
<td/>
<td/>
<td/>
<td/>
<td/>
<td/></tr>
<tr>
<td valign="middle" align="left">Male</td>
<td valign="middle" align="center">1.9%</td>
<td valign="middle" align="center">1.00&#x00B1;0.00</td>
<td valign="middle" align="center">6.8%</td>
<td valign="middle" align="center">1.77&#x00B1;1.34</td>
<td valign="middle" align="center">7.7%</td>
<td valign="middle" align="center">2.00&#x00B1;0.00</td></tr>
<tr>
<td valign="middle" align="left">Female</td>
<td valign="middle" align="center">2.2%</td>
<td valign="middle" align="center">2.25&#x00B1;1.38</td>
<td valign="middle" align="center">8.4%</td>
<td valign="middle" align="center">3.78&#x00B1;5.74</td>
<td valign="middle" align="center">8.8%</td>
<td valign="middle" align="center">4.50&#x00B1;2.77</td></tr>
<tr>
<td valign="middle" align="left">School</td>
<td/>
<td/>
<td/>
<td/>
<td/>
<td/></tr>
<tr>
<td valign="middle" align="left">Middle school</td>
<td valign="middle" align="center">1.5%</td>
<td valign="middle" align="center">1.40&#x00B1;0.89</td>
<td valign="middle" align="center">4.4%*</td>
<td valign="middle" align="center">3.35&#x00B1;6.99</td>
<td valign="middle" align="center">5.1%*</td>
<td valign="middle" align="center">2.80&#x00B1;1.78</td></tr>
<tr>
<td valign="middle" align="left">High school</td>
<td valign="middle" align="center">2.6%</td>
<td valign="middle" align="center">2.14&#x00B1;1.46</td>
<td valign="middle" align="center">11.0%</td>
<td valign="middle" align="center">2.78&#x00B1;3.00</td>
<td valign="middle" align="center">11.7%</td>
<td valign="middle" align="center">4.16&#x00B1;3.12</td></tr>
<tr>
<td valign="middle" align="left">Residence</td>
<td/>
<td/>
<td/>
<td/>
<td/>
<td/></tr>
<tr>
<td valign="middle" align="left">Dong</td>
<td valign="middle" align="center">1.9%</td>
<td valign="middle" align="center">1.25&#x00B1;0.50</td>
<td valign="middle" align="center">7.5%</td>
<td valign="middle" align="center">2.52&#x00B1;3.13</td>
<td valign="middle" align="center">8.2%</td>
<td valign="middle" align="center">2.50&#x00B1;1.00</td></tr>
<tr>
<td valign="middle" align="left">Eup/Myeon</td>
<td valign="middle" align="center">2.2%</td>
<td valign="middle" align="center">2.13&#x00B1;1.45</td>
<td valign="middle" align="center">7.7%</td>
<td valign="middle" align="center">3.41&#x00B1;5.70</td>
<td valign="middle" align="center">8.4%</td>
<td valign="middle" align="center">4.17&#x00B1;3.12</td></tr>
<tr>
<td valign="middle" align="left">Father&#x2019;s level of education</td>
<td/>
<td/>
<td/>
<td/>
<td/>
<td/></tr>
<tr>
<td valign="middle" align="left">&#x2264;Middle school</td>
<td valign="middle" align="center">5.6%*</td>
<td valign="middle" align="center">1.50&#x00B1;1.00</td>
<td valign="middle" align="center">10.1%</td>
<td valign="middle" align="center">1.50&#x00B1;1.06</td>
<td valign="middle" align="center">11.2%</td>
<td valign="middle" align="center">3.00&#x00B1;1.73</td></tr>
<tr>
<td valign="middle" align="left">High school</td>
<td valign="middle" align="center">1.6%</td>
<td valign="middle" align="center">1.75&#x00B1;0.95</td>
<td valign="middle" align="center">8.1%</td>
<td valign="middle" align="center">2.46&#x00B1;2.16</td>
<td valign="middle" align="center">8.6%</td>
<td valign="middle" align="center">2.67&#x00B1;1.15</td></tr>
<tr>
<td valign="middle" align="left">&#x2265;College</td>
<td valign="middle" align="center">1.8%</td>
<td valign="middle" align="center">2.25&#x00B1;1.89</td>
<td valign="middle" align="center">5.9%</td>
<td valign="middle" align="center">4.62&#x00B1;7.76</td>
<td valign="middle" align="center">6.9%</td>
<td valign="middle" align="center">4.67&#x00B1;4.61</td></tr>
<tr>
<td valign="middle" align="left">Mother&#x2019;s level of education</td>
<td/>
<td/>
<td/>
<td/>
<td/>
<td/></tr>
<tr>
<td valign="middle" align="left">&#x2264;Middle school</td>
<td valign="middle" align="center">2.5%</td>
<td valign="middle" align="center">1.00&#x00B1;0.00</td>
<td valign="middle" align="center">6.3%</td>
<td valign="middle" align="center">3.75&#x00B1;3.77</td>
<td valign="middle" align="center">7.6%</td>
<td valign="middle" align="center">2.00&#x00B1;0.00</td></tr>
<tr>
<td valign="middle" align="left">High school</td>
<td valign="middle" align="center">2.5%</td>
<td valign="middle" align="center">2.25&#x00B1;1.38</td>
<td valign="middle" align="center">9.1%</td>
<td valign="middle" align="center">2.06&#x00B1;1.53</td>
<td valign="middle" align="center">9.8%</td>
<td valign="middle" align="center">4.50&#x00B1;2.77</td></tr>
<tr>
<td valign="middle" align="left">&#x2265;College</td>
<td valign="middle" align="center">1.4%</td>
<td valign="middle" align="center">1.00&#x00B1;0.00</td>
<td valign="middle" align="center">5.1%</td>
<td valign="middle" align="center">5.31&#x00B1;8.56</td>
<td valign="middle" align="center">5.7%</td>
<td valign="middle" align="center">2.00&#x00B1;0.00</td></tr>
<tr>
<td valign="middle" align="left">Monthly income</td>
<td/>
<td/>
<td/>
<td/>
<td/>
<td/></tr>
<tr>
<td valign="middle" align="left">&#x003C;200</td>
<td valign="middle" align="center">3.0%</td>
<td valign="middle" align="center">1.50&#x00B1;0.83</td>
<td valign="middle" align="center">6.8%</td>
<td valign="middle" align="center">2.08&#x00B1;2.25</td>
<td valign="middle" align="center">7.7%</td>
<td valign="middle" align="center">3.00&#x00B1;1.41</td></tr>
<tr>
<td valign="middle" align="left">200-299</td>
<td valign="middle" align="center">2.1%</td>
<td valign="middle" align="center">2.33&#x00B1;2.30</td>
<td valign="middle" align="center">9.3%</td>
<td valign="middle" align="center">2.71&#x00B1;1.93</td>
<td valign="middle" align="center">9.3%</td>
<td valign="middle" align="center">4.67&#x00B1;4.61</td></tr>
<tr>
<td valign="middle" align="left">300-399</td>
<td valign="middle" align="center">0.0%</td>
<td valign="middle" align="center">0&#x00B1;0.0</td>
<td valign="middle" align="center">5.4%</td>
<td valign="middle" align="center">5.71&#x00B1;10.73</td>
<td valign="middle" align="center">5.4%</td>
<td valign="middle" align="center">5.71&#x00B1;10.73</td></tr>
<tr>
<td valign="middle" align="left">&#x2265;400</td>
<td valign="middle" align="center">1.8%</td>
<td valign="middle" align="center">1.00&#x00B1;0.00</td>
<td valign="middle" align="center">7.4%</td>
<td valign="middle" align="center">3.21&#x00B1;4.19</td>
<td valign="middle" align="center">8.3%</td>
<td valign="middle" align="center">4.21&#x00B1;4.20</td></tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table4-fn1-jkaoh-42-3"><p>*<italic>P</italic>&#x003C;0.05.</p></fn>
</table-wrap-foot>
</table-wrap>
</sec>
</back>
</article>