Summary: A pilot study in asample of 7 children with deep bite and between 3 and 5 years old was carried out to evaluate theelectromyographic changes after Planas Direct Tracks (PDT) adaptation. An initial electromyographicregister of the masseter and anterior temporal right muscles was made while the children chewed gum.A month after the PDT adaptation, a second electromyographic register was taken and comparisons weremade. Although an electromyographic activity decrease tendency was presented, the changes were notstatistically significant. Key words: Planas Direct Tracks. Deep Bite. Electromyograhy.EMG.