摘要
The study of the craniomandibular biomechanics is related to the system of predominant lever and of the relation between function and mechanically induced deformations. This study has the purpose of evaluating the chewing muscular dynamics in the surface electromyography Seventeen people of both sex, medium aged about 25, were selected, white skin and presenting Class I of Angle without apparent sign and symptom. The electromiographic data were obtained bilaterally from the masseter muscles, anterior temporal portion at the rest position and isometric position. Medtrace passive bipolar surface electrodes were used coppled to a pre-amplifier, forming a circuit corresponding to a differential circuit. The registrations of the electric signals were caught by EMG- 800C equipment of Brazil EMG System Ltda with eigth channels, sample frequency of 2 KH and 16 bits resolution, digital filter with a band pass of 20-500 Hz. A comparison was through %26quot;t%26quot; Student or a Man- Whitney test according to the normality or not of the distribution, respectively. The results have shown important differences between the tasks but without sexual dimorphism. All these results indicate to the electrical activity of the temporal muscle in its anterior portion was bigger than the masseter muscle in rest position and the masseter muscle presented a higher potential of action than the anterior temporal muscle in isometric. El estudio de la biomec芍nica craneomandibular se relaciona con el sistema de palanca predominante y la relaci車n entre la funci車n y deformaciones mec芍nicamente inducidas. Este estudio tuvo el prop車sito de evaluar la din芍mica muscular de la masticaci車n en la superficie electromiogr芍fica en 17 personas de ambos sexos, con edad media de 25 a os, de piel blanca y que presentaban clase I de Angle, sin aparentes signos y s赤ntomas. Los datos electromiogr芍ficos fueron obtenidos bilateralmente desde los m迆sculos maseteros, la porci車n anterior del m迆sculo temporal en posici車n de descanso y en posici車n isom谷trica. Electrodos bipolares de superficie pasiva Medtrace fueron utilizados acoplados a un pre-amplificador, formando un circuito que corresponde a un circuito diferencial. Los registros de las se ales el谷ctricas fueron capturados por el equipo EMG- 800C de Brazil EMG System Ltda.. con 8 canales, frecuencia de muestreo de 2 KH y 16 bits de resoluci車n, un filtro digital con una banda de paso de 20-500 Hz. La comparaci車n fue hecha mediante %26quot;t%26quot; Student o la prueba Man-Whitney de acuerdo con la normalidad o no, de la distribuci車n, respectivamente. Los resultados mostraron im