Vol 6, No 1 (2018) ISSN 2167-8677 (online) DOI 10.5195/d3000.2018.82 http://dentistry3000.pitt.edu New articles in this journal are licensed under a Creative Commons Attribution 4.0 United States License. This journal is published by the University Library System, University of Pittsburgh as part of its D-Scribe Digital Publishing Program and is cosponored by the University of Pittsburgh Press. Maximum mouth opening in healthy children and adolescents in Istanbul Mine Koruyucu 1 , Derya Tabakcilar 2 , Figen Seymen 1 , Koray Gencay 1 1 Istanbul University, Faculty of Den6stry, Department of Pedodon(cs, Istanbul, Turkey 2 Yeditepe University, Faculty of Den7stry, Department of Pedodon(cs, Istanbul, Turkey Abstract Objec&ves: Mouth opening capacity is o0en regarded as one of the important parameters for evalua7ng the func7on of the temporomandibular joint (TMJ) and mas,catory muscle status. A reduced mouth opening capacity may be one of the first clinical signs of TMJ involvement. The purpose of this study was to create age related percen;les for the maximal interincisal distance (MID) of healthy children. Methods: The pa’ents admi.ed for rou’ne dental examina- !ons to Istanbul University Faculty of Den!stry, Department of Pedodon!cs were included in this study. The interin- cisal measurements were performed with metallic calliper and also malocclusions were recorded for all children. Oneway Anova test, Tukey HDS test, Tamhane’s T2 test and Student t test were used for sta;s;cal analysis. Results: The study popula.on comprised of 1059 (569 males, 490 females), 3-to 15-year-old (mean age 8.82±3.06) children. The mean score of maximal inter-incisal distance was found 33.24±5.54 for females; 33.32±5.71 for males. There was no sta’s’cally significant difference according to gender (p=0.815; p>0.05). The mean score of maximal inter-incisal distance was found 28.63±4.34 for 3-5 years; 33.52±4.84 for 6-11 years; 37.35±5.52 for 12-15 years children. Sta2s2- cally significant differences were found between age groups (p: 0.001; p<0.01). The mean score of maximal inter- incisal distance was found 32.9±5.6 for class I; 34.92±5.51 for class II; 35.2±5.36 for class III malocclusions. Sta:s:cally significant differences were found between malocclusion groups (p:0.001; p<0.01). Conclusion: The result of this study indicated that posi/ve rela/onship between the maximum mouth opening and age and malocclusion. Cita%on: Koruyucu M, et al. (2018) Maximum mouth opening in healthy children and adoles- cents in Istanbul. Den$stry 3000. 1:a001 doi:10.5195/d3000.2018.82 Received: December 11, 2017 Accepted: February 21, 2018 Published: July 13, 2018 Copyright: ©2018 Koruyucu M, et al. This is an open access ar!cle licensed under a Crea!ve Commons A"ribu%on Work 4.0 United States License. Email: mine.yildirim@istanbul.edu.tr Introduction Palpation of muscle and joint, occlusal and radiographic examination are performed for assessment of mandibular func- tion. To be able to assess tem- poromandibular joint (TMJ) func- tion, the primary value to be known is how much joints move when mouth is opened fully max- imum mouth opening (MMO) [1,2]. MMO is “ the greatest dis- tance between two central inci- sors (maxillary and mandibular) at the midline when measured from their incisal edges during the pos- sible wildest opening of the mouth” according to many re- searchers [3,4]. Mouth opening limitation may be associated with some clin- ical situations like temporoman- dibular disorders, odontogenic in- fections, oral malignancies, sub- mucous fibrosis, mandibular frac- tures, myopathies, and trauma [5]. Sex, age and height have an impact on how much a person can open their mouth. As an im- portant step, before diagnosing that a person is suffering from lim- ited mouth opening, it is necessary to acknowledge normal opening of the population [6]. Some studies researched children and adoles- cents MMO values among differ- ent populations (Table 1) [6–15]. Also, most of these studies re- vealed as age increases, MMO in- creases as well. Moreover, girls have a decreased MMO compared to boys. For this reason, it is im- portant to define normal MMO values for each specific popula- tion, so that it is possible to diag- nose whether a person suffers from reduced mouth opening. The aim of this study was to evaluate age related percentiles for the maximal inter-incisal dis- tance of healthy children, based on sex and malocclusion.