Biomedical subjects

M Akanishi

Publications and source records attributed to M Akanishi.

16 recordsLinked to original sources

PubMed1990

[Electromyographic study on motor skill in chewing movement. A new concept on relating electromyographic analysis to chewing movements].

This article was aimed to propose a new concept on evaluating electromyographic activities of masticatory muscles during chewing movements viewed from the standpoint of motor skill. Correlation coefficients between the ratio of lateral distance to ten vertical level set at 0.5 mm to 5.0 mm with 0.5 mm step from the end of closing phase and activities of bilateral masseter, anterior and posterior temporalis in each chewing stroke were evaluated using raisin, peanut, soft and hard testing gum in five subjects. Habitual chewing side always demonstrated less numbers of subjects who showed high correlation coefficients especially in the case of soft testing gum.

Chewing Gum↗

PubMed1989

[Relationships between tooth loss and electromyographic activities of masticatory muscles].

For purpose of evaluating the characteristic of electromyographic activities of masticatory muscles with front or molar tooth loss, electromyographic activities of masticatory muscles and mandibular movements during tooth tapping and gum chewing were investigated in each group of tooth loss, and were compared with those of control group. The results were as follows. 1. In reference to the group with front tooth loss, 1) On tooth tapping, each S.D. of the time parameters of electromyographic activities of jaw closing muscles especially masseter and posterior temporalis was small, and that of jaw opening muscle was large. 2) On gum chewing, offset of jaw closing muscles' activities especially masseter and anterior temporalis were delayed. 3) On both tooth tapping and gum chewing, there was no difference in mandibular movements from control group. 2. In reference to the group with molar tooth loss, 1) On both tooth tapping and gum chewing, each S.D. of the time parameters of electromyographic activities of jaw closing muscles was large. 2) On tooth tapping, S.D. of opening ratio was large. 3) On gum chewing, both S.D. of chewing cycle and opening ratio were large.

Electromyography↗

PubMed1989

[Electromyographic study on the effects of head position to head and neck muscles].

The purpose of this study is to reveal the relationship between the head position, and the neck and head muscles. At 4 head positions, the activities of masseter, anterior temporal, anterior digastric, sternocleidomastoid and trapezius muscle of ten normal subjects standing straight were investigated electromyographically with surface electrodes during voluntary maximal clenching in centric occlusion. Head positions were right tilting, left tilting, up-right and natural head position. The results obtained were as follows; 1. During head tilting, the activities of anterior digastric and sternocleidomastoid muscle on the tilting side were increased, the activities of masseter and trapezius muscle on the opposite side of the tilting side were increased, the activity of the anterior temporal muscle did not vary from the activity during up-right head position. 2. During natural head position, only the activity of sternocleidomastoid muscle on the natural tilting side was increased.

Electromyography↗

PubMed1989

[Psychosomatic aspects of the patients with stomatognathic dysfunction. 2].

Various kinds of mind stress are prevalent in our society today. Especially, in the current society, number of patients who suffered from mind stress have been increased. And to our interest, many of them tended to show dysfunction in stomatognathic system. We have reported in the previous report that psychosomatic factors not only occlusal factors played an important role in the function of stomatognathic system. If the stomatognathic dysfunction patients were treated without the care of psychosomatic factors, effect of the treatment may sometimes be resulted in slow or uncertain cure. So we must analyze the psychosomatic condition of the patients in order to diagnose and treat them effectively. Therefore we studied the relationship between the psychosomatic factors and the social condition such as age, sex, type of job, marital status. The personality test was done among the general patients, who belonged to three different companies, using a questionnaire such as CMI test in regard to general patients. The results indicated that the difference of social condition developed different tendency in psychosomatic condition. This suggestion that psychosomatic factors must be taken care in order to diagnose and treat the patients.

Female↗

PubMed1989

[Electromyographic study on lateral jaw movements].

This study aims to analyse how jaw-closing muscle activities are modulated during lateral jaw movement. Jaw movements were recorded by Sirognathograph (Siemens Co.) and electromyograms were simultaneously recorded from bilateral masseter, anterior temporal and posterior temporal muscles in 20 young adults without any stomatognathic dysfunction. Each subject sat upright in the chair with the head unsupported. The lateral jaw movements from the intercuspal position were guided three times for each lateral excurtion (right and left). The data were recorded on magnetic tape and later analysed by use of a computer. Following variables were analysed; the number of contacted teeth, the position of contacted teeth, the muscle activities during lateral jaw movement. The results can be summarised as follows; 1) The working-side posterior temporal muscle showed obvious activity in more than 90% subjects during lateral jaw movement. However, this muscle activity was not influence by the number or position of the contacted teeth. 2) The right side masseter muscle tended to show the obvious activity during both right and left lateral jaw movement. The results of this study suggest the difference in the activities between masseter and temporal muscle during lateral jaw movement.

Dental Occlusion↗

PubMed1988