Swallowing is the most important movement in the oral cavity as an inret of nutrition essential to the maintenance of the human life. At that time, patients wearing full dentures due to edentulous jaw have comparable movements to those observed in the dentulous jaw. Namely, the tongue press its tip against the rugae of palate in the first stage of swallowing, and then gradually establishes contact between its back and the posterior portion of palate with pressure to transport the food into the pharynx. During this couse, the contact of the posterior portion of tongue with dentures plays an important role in stabilization of dentures.
Strack has proposed that arrangement of artificial teeth in the same place as that of the natural dentition is the best way to maintain the stability of denture.
In recent years, techniques of making dentures have been improved with the advancement of dental materials. I devised a method of simultaneously making impressions of upper and lower jaws using a injection device and a silicon impression material. I have routinely used this new system to make full dentures for clinical cases.
On this occasion, registration of interocclusal relation, gothic arch tracing, simultaneoustaking of upper and lower impressions, and face bow transfer will be performed in front of you using patients, from the initial examination to the setting of full dentures.

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The tragus of the ear varies in its form and shape, hence its role as a posterior reference for alatragal plane and tragus canthus line is very subjective. Further, the various tragal references recommended in the literature are not always recognisable nor definable.

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The purpose of this study was examine the criterion of the vertical dimension without dentition and the ANS-Me distance was measured on the lateral standard radiogram of the head in 22 patients without dentition who were classified into the stable group of the mandiblar position and the unstable group of its.
As a result, the male's and female's mean of the best vertical dimension in the stable group was closer to the mean orthodontic adult vertical dimension determined in healthy subjects with dentition than the unstable group's one, and also the mean of the best vertical dimension in the unstable group was lower 5 mm than the stable group's one.
Therefore, it's possible to get the reliable criterion of the best vertical dimension in edentulous patients by using the method of this study and increasing samples.

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To analyse the relation between the occlusion and the mandibular position or movement, the use of the mathematical model of the mandibular movement is effective. However, the results of the analyses can not be shown visually by mathematical expressions and computed data only. Since it is important to present them visually so as to be understood easily and to show the effectiveness of theoretical analyses, drawings and graphs were devised.
The items of drawings and graphs devised are as follows:
1. Moving paths of teeth on the tooth arrangement (drawings) .
2. Influences of condylar path and incisal path on cusp path (drawings) .
3. Influences of condylar path and incisal path on the amount of disocclusion on a living body (graphs) .
4. Influences of the adjustment value of condylar path and the adjustment value of incisal table on the amount of disocclusion on an articulator (graphs) .
5. Influences of condylar path and incisal path on the amount of disocclusion on various molars (graphs) .
The methods to read the drawings and graphs were described and the signif icances of them were discussed. In result, the effectiveness of computation using the mathematical model of the mandibular movement was shown.

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Prosthetics is required to accomplish restoration of the function of the teeth or the dentition. Prostheses placed in the oral cavity are required to be compatible to the living body and to perform their function over a long period. Occlusion is undoubtedly a key to successful prosthetics.
We, therefore, evaluated how dentists and dental technicians should cooperate to implement better occlusion.
In this study, to re-establish this point, we selected a few basic problems and evaluated each of them from the viewpoints of dentists and dental technicians.

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In daily practice, it is often difficult to diagnose cases in which bite raising is indicated. Changes that have been created over the years can not be easily modified. In this study, we observed a case in which rather unreasonable bite raising had been performed ten years previously. This case was treated with bite raising as part of prosthetic treatment, resulting in a loss of anterior guidance. The patient showed significant modification of occlusion to compensate for the loss of anterior guidance, leading to the recovery of the original occlusion. Mechanisms of this modification process were studied by following the recovery course.
We concluded that the patient successfully adapted to the changes in occlusion by greatly modifying his body. We not only were impressed by the adaptability of the living body, but also considered whether prostheses can be created that can harmonize human bodies.

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In recording of the centric relation by the Dawson technique, appropriate leading was ensured by the use of a body guard chair based on the ergonomic theory.

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