Association between occlusal force and physical functions in preschool children: a comparison of males and females.

[Purpose] To determine and compare changes over time in the physical strength of male and female children aged 4-5 years by measuring physical functions such as occlusal forces. [Subjects and Methods] The occlusal force, weight, height, grip strength, standing long jump, ball throwing, timed up and go (TUG), and the 25-m run time were measured of 331 children to determine their physical strength. All the children understood and were capable of completing all tests. [Results] Occlusal force among male infants significantly correlated with all items except ball throwing. Stepwise multiple regression analysis independently associated occlusal force with grip strength. In contrast, occlusal force of female infants significantly correlated with all the tested items. Stepwise multiple regression analysis also independently associated occlusal force with grip strength and TUG in females. [Conclusion] Grip strength indicating upper-limb muscle strength correlated with occlusal forces in both male and female children, whereas TUG, balance and walking ability indicating muscle strength of the lower limbs, correlated with items relevant to everyday functions in female infants. These findings show that different factors are involved in the occlusal forces of male and female children.