The objective of the study was to analyse quantitatively palatal morphology in bruxist and non-bruxist children with mixed dentition. Twenty-three children with mixed dentition were classified as bruxist according to their anxiety level, audible occlusal sounds related by the parents and signs of temporomandibular disorders; 23 children were control subjects matched for gender, age, and dental formula. The maxillary dental arches of all subjects were reproduced from alginate impressions cast in dental stone with a standardized technique. The casts were digitalized and mathematical equations were used to obtain the form of the palate in the sagittal, frontal and horizontal planes. Bruxist children had a statistically significant longer palate in the sagittal plane than control children; palatal shape differed especially in correspondence of the third, fourth and fifth teeth, bruxist children showing a relatively higher palate than control children. In this pilot study, sagittal plane differences in the palate between bruxist and non-bruxist children matched for age and gender were found. Further investigations are needed to understand better the clinical implications of the findings. Results should be taken into account in the diagnosis of the occlusal development in children with parafunctions to prevent future abnormalities: a bruxist child may have bigger dental arches than a normal child.