Task‐Related Differences in Lip Motor Performance Between Children and Adults During Blowing and Sucking: A Composite Sensor Study

BACKGROUND: Objective assessments of lip-closing function in children are increasingly of interest, but the task-specific, age-related characteristics of lip motor coordination remain unclear. OBJECTIVE: To compare the lip motor performance of adults and children during blowing and sucking using a composite sensor (CS) that simultaneously measures lip-closing pressure (LP), intraoral pressure (IP) and upper orbicularis oris electromyographic (EMG) activity. METHODS: In this cross-sectional study, 30 children (mean age 8.7 ± 1.7 years) and 25 adults (mean age 27.4 ± 3.9 years) performed blowing and sucking tasks. LP, IP and EMG activity were recorded simultaneously using a CS. Integral values of LP, IP and EMG were calculated and the relationships between pressure and EMG activity were analysed to identify any task- and age-related differences. RESULTS: LP and IP were lower in the children than in the adults during both tasks. During blowing, LP correlated with EMG activity only for children, whereas IP correlated with EMG activity for both groups. During sucking, LP correlated with EMG activity only for adults and IP showed no significant correlation with EMG activity. CONCLUSION: Lip motor performance differs between children and adults in a task-related manner. The distinct relationships among EMG activity, LP and IP imply qualitative age-group differences in perioral motor coordination rather than simple differences in strength. The evaluation of lip motor performance under multiple conditions may provide a more comprehensive means of assessing age-related variations in lip motor function in clinical settings.