The masticatory muscle activity during chewing was studied by means of electromyography (EMG) in 13 women treated with bridges supported on osseointegrated implants and compared with that in 10 dentate control subjects. The factors studied were the changes of the maximal mean voltage amplitude and the duration and coordination of activity during chewing of peanuts, bread, and apple when comparing the first three with the last three out of ten randomly selected chewing cycles. Patients with implant-supported bridges chewed with approximately the same muscle activity during the whole chewing sequence, whereas the control subjects had a reduced activity at the end of the chewing act.