Maximum mouth opening in healthy children and adolescents in Istanbul

Objectives: Mouth opening capacity is often regarded as one of the important parameters for evaluating the function of the temporomandibular joint (TMJ) and masticatory 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 percentiles for the maximal interincisal distance (MID) of healthy children. Methods: The patients admitted for routine dental examinations to Istanbul University Faculty of Dentistry, Department of Pedodontics were included in this study. The interincisal 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 statistical analysis. Results: The study population 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 statistically 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. Statistically 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. Statistically significant differences were found between malocclusion groups (p:0.001; p<0.01). Conclusion: The result of this study indicated that positive relationship between the maximum mouth opening and age and malocclusion.