Orthodontic treatment of children with anterior open bite and posterior crossbite: An analysis of the stomatognathic system.

Dental malocclusions are deviations from normalities due to the inadequate growth and development of the dental arch which provides functional changes to the stomatognathic system. The aim of this longitudinal study was to evaluate the electromyographic activity (EMG) the masseter and temporalis muscles, strength of the orofacial tissues and occlusal force of children with anterior open bite (n = 15) and posterior crossbite (n = 20), 7 days after the removal of the orthodontic apparatus. A fixed horizontal palatal crib was used in the treatment of anterior open bite and the fixed appliances Hyrax or MacNamara was used in the treatment of posterior crossbite. EMG of the masticatory muscles was recorded using an electromyograph with wireless sensors during mandibular tasks. Habitual chewing was assessed using the integral of the linear envelope of the electromyographic signal in the masticatory cycles. The strength of the tongue and facial muscles was measured using the Iowa Oral Pressure Instrument. T-Scan was used to analyze the force of occlusal contact. Molar bite force was measured by digital dynamometer. Significant differences (p < 0.05) were found in the EMG data of the masseter and temporalis muscles in the static and dynamic mandibular tasks. There were no significant difference in strength of orofacial tissues, occlusal contact force and molar bite force 7 days after the removal of the orthodontic apparatus. The results of this study suggest that the orthodontic treatment of anterior open bite and posterior crossbite in children promoted functional alteration in the electromyographic activity of masseter and temporalis muscles.

Impact of Hemorrhagic Stroke on Molar Bite Force: A Prospective Study.

Stroke is a neurological deficit of cerebrovascular origin that promotes physical impairments of adult individuals. The present study is aimed to demonstrate whether hemorrhagic stroke affects the maximum molar bite force. The prospective study carried in Centro Universitario Claretiano de Batatais, Brazil, determined the distribution of the sample into two groups: hemorrhagic stroke group (n=18, median age, 62.5 years) and disease-free group (n=18, median age, 62.0 years), with 10 men and 8 women in each group. Subjects were paired one-to-one (age and body mass index). The dynamometer was used to measure the maximum molar bite force (right and left). All analyses were performed with a significance level of 5% (Student's t-test). Differences were found on the right (p=0.048) and left (p=0.042) molar bite force, with lower bite force (both sides) in hemorrhagic stroke group. The study suggests that hemorrhagic stroke negatively affects the maximum molar bite force and necessitates changes in food intake to nutritious and softer consistency foods.