Masticatory function in children with Down syndrome

The objective was to study masticatory function of 8 to 10-year-old children with Down syndrome (DS) through the evaluation of maximum occlusal force and masticatory performance (via medium particle size) and compare it to that of children of the same age without DS.

A convenience sample of eight, 8-10-year-old children with DS were included in this cross-sectional study. The study had ethical approval and parents provided informed consent. Exclusion criteria were large carious lesions, dental pain or previous orthodontic/orthopedic treatment. Masticatory performance was evaluated with an artificial test food (Optosil Comfort®) after 20 cycles and at swallowing threshold. The chewed material was collected, dried and sieved. The material on each sieve was weighed; the weights were used to calculate medium particle size. Maximum occlusal force (1st permanent molars) was determined using the GM10 Nagano Keiki Co.™ portable transducer. The number of cycles until swallowing threshold, cycle and sequence durations were also compared. The data for the reference group (n = 32) came from a previous study in children of the same age. Descriptive statistics as well as comparisons with Mann-Whitney tests and simple and multiple regression analysis were performed. Cutoff was set at p≤.05.

Medium particle size is larger by 44% after 20 chewing cycles and 75% at swallowing threshold (p<.05) in children with DS. Median maximum occlusal force was 254 kN in DS children and 499 kN in children without the syndrome (p<.001). 48% of the variance in maximum occlusal force is explained by having DS. There were also significant differences in sequence and cycle durations. All significant differences had large effect sizes (˃1). Although the children with DS chewed more cycles before swallowing threshold the difference was not significant.

Children with DS have approximately 50% of the masticatory performance and maximum occlusal force of children of the same age without DS. These findings can be associated to the feeding problems reported in children with DS.