The silent period in the masseter and in the anterior portion of the temporal muscle during tooth tapping, the rate of tooth tapping and the jaw jerk reflex evoked by a tap on the chin were compared in individuals with oral implant bridges and with natural teeth. Thirteen women with osseointegrated oral implant bridges in one or both jaws, aged 42-59 years, were compared with 10 women, aged 42-64 years, with natural teeth. There was no difference between women, aged 42-64 years, with natural teeth. There was no difference between women with implant bridges and those with natural teeth in tooth tapping rate or in the occurrence, latency or duration of the jaw jerk reflex. A silent period during tooth tapping was found in 12 of the 13 women with implant bridges. The latency of the silent period was the same as in the subjects with natural teeth but the duration tended to be somewhat longer. The jaw jerk and the silent period were the same in individuals with implants in both jaws as in the whole implant group. It is therefore concluded that periodontal or mucous membrane receptors cannot be solely responsible for the silent period.