Background: Anterior open bite (AOB) is the vertical separation between upper and lower teeth when all other teeth are in maximum intercuspation. It is considered abnormal when it affects patient's function, speech, mastication, future dental health risks and aesthetics.
Aim: The current study was conducted to determine the prevalence of anterior open bite and its etiological factors in a group of Egyptian children aged 8 years and above.
Methods: The sample comprised 115 participants aged between 8 and 10 years, attending the Outpatients' Clinic of Pediatric Dentistry and Dental Public Health Department, Faculty of Dentistry, Cairo University. AOB was assessed on study cast models using digital caliper. Increased overjet, abnormal oral habits, and parents' educational level were checked. A close ended questionnaire was answered by patients' guardians. Data were statistically analyzed with SPSS software package (version 21 SPSS Inc., Chicago, USA).
Results: About 24(20.9%) of the 115 participants had AOB, 82 (71.2%) had normal overbite, 9 (7.8%) had increased overbite. Overjet relationship was increased in 51(44.4%). The most common etiological factor was mouth breathing 13(11.3%). Abnormal oral habits revealed higher percentages of tongue thrust 5 (7.2%), thumb sucking 4(5.8%) and lip biting 6(8.7%) in girls. Boys revealed higher percentages regarding mouth breathing 7(15.2%) and nail biting 1(2.2%). There was significant low positive correlation between parents' educational level and the amount of AOB (r < 0.5, P-value < 0.05).
Conclusions: Prevalence of AOB is relatively low, with no sex predilection. Abnormal oral habit may be a causative factor of AOB.