en Dentistry Original Article Original Article <strong>Background</strong>: Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent neurological disorders in children, and due to its symptoms, patients might be unable to maintain proper oral health.&nbsp;<br> <strong>Objectives</strong>: In this study, the correlation between ADHD and oral health was investigated.&nbsp;<br> <strong>Methods</strong>: In the current analytic cross-sectional study, 36 children with ADHD aged 12-14 years and 36 healthy children of the same age were clinically examined regarding decay-missed-filled teeth (DMF) index and the gingival bleeding index (GBI). Two bitewing radiography images were acquired from each subject; additionally, the parents completed questionnaires regarding oral habits. To analyze the data, independent t-test, chi-squared test, and the Fisher test were employed, and for calculating the values, the SPSS software, version 16.0, was used.&nbsp;<br> <strong>Results</strong>: The mean DMF index in test and control groups was 7.19&plusmn;3.76 and 4.97&plusmn;2.37, respectively, which was statistically significant (P=0.004). The mean GBI in the test and control groups was 35.05&plusmn;30.69 and 30.88&plusmn;21.04, respectively. Regardless of the higher mean GBI in the test group, the difference was not significant (P=0.504). Meanwhile, bruxism was detected in 16.7% of the children in the test group, which was significant (P=0.025).<br> <strong>Conclusion</strong>: Children diagnosed with ADHD had a higher DMF index and poor dental hygiene. Bruxism was also more commonly detected in these patients.&nbsp; Attention deficit hyperactivity disorder (ADHD), Bruxism, Permanent dentition, Dental caries, Oral health 139 144 http://jpr.mazums.ac.ir/browse.php?a_code=A-10-1197-1&slc_lang=en&sid=1 Seyedeh Porousha Mahjoub Khatibani Dr.p.mahjoub@gmail.com 100319475328460012420 100319475328460012420 No Department of Pediatric Dentistry, Dental Sciences Research Center, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran. Shaghayegh Rabiei Shaghayeghrabiei00@yahoo.com 100319475328460012421 100319475328460012421 No Dental Sciences Research Center, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran. Maryam Kousha Maryamkosha@yahoo.com 100319475328460012422 100319475328460012422 No Department of Psychiatry, Shafa Hospital, Guilan University of Medical Sciences, Rasht, Iran. Javaneh Vejdani jvjdani@yahoo.com 100319475328460012423 100319475328460012423 No Department of Pediatric Dentistry, Dental Sciences Research Center, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran. Arayeh Maleki maleki.arayeh@gmail.com 100319475328460012424 0009-0004-8130-9794 No Tehran University of Medical Sciences, Tehran, Iran. Dina Maleki dinamaleki74@gmail.com 100319475328460012425 100319475328460012425 Yes Dental Sciences Research Center, School of Dentistry, Guilan University of Medical Sciences, Rasht, Iran.