Loading a sequential repetitive click sound signal with a constant frequency of 1.3Hz, 15 healthy subjects were made to perform anticipated jaw tapping movement. They were instructed to adjust their movement so as to be obtained a coincidentaneous tooth contact with the signal.
1) An acquisition of the anticipated tapping movement was nearly accomplished by the time of the 3 rd or the 4 th acoustic signal.
2) After cessation of the signal, all subjects made a surplus movement. It's time differences between the onsets of EMG bursts and of SP and the signal were closed to the corresponding values of the tapping at the last signal.
3) After the 3 rd signal, the movement tended to be adjusted so that the tooth contact preceded the signal (P<0.05).
4) DOSPs in the load tapping were shorter thanthose in the tapping ad lib (P<005), DOSPs in the former became to be longer with increasment of number of trials (P<005).
5) It could be interpreted that an early learning process of the anticipated movement would be almost accomplished by the time of the 14 th or 15 th signal, following by habituaion, and that the large extent of the adjustment should be done by“subsequent performance control”, using the informations obtained from the past trial.

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In the full denture prosthodontics, an object of study and treatment are old ages in the main. Then the improvement of lowerd masticatory function being a kind of physical body function, is very important. Then, the masticatory force and electoromyographic record are measureded during bewing a food (peanuts, ham, pickled radish). Furthermore, the integrated masticatory force and activity of masticatory muscle are observed.
1. The masticatory forces were the largest on the peanuts. The largest masticatory forces were measured in 3 rd or 4 th period, the smallest in 1 st. The rhythm (the duration, the interval, the term and the ratio of duration to the term) were the largest on the pickled radish. The integrated masticatory forces were measured same value in the 2 nd or 5 th period, the smallest in 1 st.
2. The number of masticatory times were most on the pickled radish.
3. As for the rhythm of electric discharge of masticatory muscles, the duration and the ratio of the duration on the term were the largest on the pickled radish. The largest D and D/T were measured in 1 st period and the smallest in 5 th. The interval and the term were the largest on the pickled radish. The largest I and T were measured in 5 th period and the smallest in 1 st. As for the activity of masticatory muscles in masticating various foods, peanuts and ham were the largest in 3 rd and the smallest in 1 st, pickled radish were the largest in 2 nd or 4 th, the smallest in 3 rd or 5 th. Among foods, the pickled radish were measured the largest.
4. The activities of masticatory muscles which were needed for the intergrated masticatory force unit in various foods were the largest in 1 st period, the smallest of peanuts and ham were in 5 th, pickled radish in 4 th. Among foods, the ham were measured the largest.

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The objective of this research is to investigate the behavior of the interproximal contact in function.The relative movement between the second premolar and the first molar in the mesio-distal direction was measured, using the strain-gauge as the transducer. Based on the result of this experiment, the following conclusions can be made:
1. During biting, the distance between two measured points placed respectively on the buccal and lingual surfaces of the second premolar and the first molar decreased.
2. During mastication, the distance between two measured points consistently decreased and recovered at every stroke.
3. When the tooth was not in function, it seemed that the tooth did not contact with the proximal teeth and pulsated in the alveolar bone mainly due to the circulation of the blood in the periodontium.
4. During mastication, the tooth was pushed into the alveolar bone, and was displaced in the direction toward a decrease in dental arch width. At the same time the proximal contact became tighter, which will probably protect the interdental papilla from food impaction.

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