The experimental model modified from the automatic measuring system, being able to measure the movement of condyle in three dimensions, had been studied and improved. And, the new electronic measuring system of the mandibular movement being applicable for the clinical operation was developed.
The features of this system are such as the followings;
1. A one-dimensional senser consisting of the light sources with optical fibers and the CCD line image senser was newly developed for this measuring system. The method measuring the movement of the mandible in three dimensions was established by means of employing three of those sensers.
2. Principle of the calculation was introduced so that the movement of the center of condyle was shown based on the results of the measurement by means of the sensers fixd anterior to the incisal point.
3. Each configuration of the system was developed, and the total system consisting of senser, microcomputer, fully adjustable articulator, and etc. was established.
4. This measuring system had the capability to measure and display the movement of condyle as accurate as the movement of the center of condyle would have directly been measured. For this, the technical errors relatively common to the pantographic procedures, such as transferring the tracings to the articulator, were reduced tremendously.
5. Since this system was not only easy but simple to operate, it must be said that it is the measuring system of the mandibular movement being effective and applicable for the clinical usage.

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Fischer's angle is defined as the angle formed by the path of the advancing condyle during lateral movement and the path of the advancing condyle during protrusive movement, as viewed in the sagittal plane. Although the term Fischer's angle has such an clear definition, and this angle has long been believed to be an important characteristic of condylar path, several studies have thrown some doubts on its existence.
It may be pointed out that the controversy of existence of Fischer's angle is two-fold. One aspect of the controversy concerns the existence of Fischer's angle itself, and the other concerns the effect of central bearing plate configuration upon features of condylar path including Fischer's angle.
It was the purpose of this study to observe the effects of central bearing plate configuration upon condylar path. For this, Fischer's angle being one of the features of condylar path was investigated in the sagittal plane.
Five adults, who were diagnosed to have normal occlusion, were selected. Fischer's angle was recorded for each of them by means of modified pantograph with each of three different types of central bearing plates, namely Denar-type, Stuart-type, and flat-type, respectively. Denar-type central bearing plate had concave contour, where protrusive and lateral path had inclinations of 15°and 18°, respectively against occlusal plane. Angular difference of those path was 3°. Stuart-type central bearing plate had also concave contour, where both protrusive and lateral paths had inclinations of 16°against occlusal plane, and angular difference of those paths was 0°. Among three types of central bearing plates, Stuart-type had the feature being located more parallel to the sagittal condylar path. Flat-type central bearing plate had literally flat contour, where both protrusive and lateral paths had 0°inclinations against occlusal plane, and angular difference of those was 0°. Flat-type, however, was not located on the dentition as parallel as Stuart-type to the sagittal condylar path.
Observation revealed that Fischer's angle recorded with Denar-type central bearing plate was the largest, that with Stuart-type was the smallest, and that with flat-type was the medium.
The followings are the findings of this study.
1. There exists Fischer's angle.
2. Fischer's angle was affected as configuration of central bearing plate altered. This fact may connotate that Fischer's angle may be affected as anterior guidance alters.
3. Angular difference between protrusive and lateral paths of central bearing plate had effect upon Fischer's angle. For instance, the more the angular difference was, the more the Fischer's angle was.
4. Fischer's angle became smaller as central bearing plate was located to be more parallel to the sagittal condylar path.

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Based on clinical experience over ten years, provision of ridge support for fabrication of removable partial denture was considered to be important for support and stability of the dentures.
About 1960, Dr. K.H. Körber improved some disadvantages of the old telescope system and developed so-called Konuskronen telescope. Many clinical results have been reported, since the theoretical background and prognosis of the new device were introduced to Japan.
It is without doubt a superb device, however, avthor has experienced some difficulty in it, as follows:
1) In the case where anterior teeth are the abutments, those are replaced by full-veneered gold crowns. when the partial denture is removed, anterior gold crowns show. This may cause an esthetic problem, which delicately affects to the patient's psychology.
2) Retention of Konuskrone is derived from the forces of friction between inner and outer caps. In this mechanism, very slight space is required between the occlusal surface of an inner cap and the inside of an outer cap. The existence of this space, however, causen such problems as follows:
(a) Substance of an outer cap of an abutment tooth at the time when it functions, may loose centric stops.
(b) When veneered with resin on the outer cap and if shoulder is made at the cervical part of an inner cap, the retention may be lost due to contact of this part.
It is considered, as a counterplan, that the shoulder part of an outer cap should be cut away slightly or an inner cap to be tapered. The former has a demerit in plaue intrusion, while the latter in contour of an outer cap.
(c) The support depending merely upon the effect of friction, author feels, show some difficulties in revelation of such grasping force as per an operator intends, and in adjusting at the time supporting force decreases after years later.
In order to overcome these disadvantages, author has conceived a new supporting device combining those advantages of the abovementioned device with I.C. attachment. Author has obtained, thereupon, good results in clinical application. Since the device has been newly conceived, author will need time to observe and pursue the prognosis after years.

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Among various types of mutilated abnormal occlusion obserbable in Japanese, some of those cases show diasthema or prognathism of auteriors, and other symptoms due to the decrease of oral volume, and seem to be impossible to treat due to imbalance existing between load being applied by masticatory musculature and relatively weak support provided by periodontium.
It was, however, tried to treat such cases with a long term basis. Treatments included general check-up and local check such as plaque control, periodontal and endodontic treatments, bite raising, minor tooth movement, and so on. This report was dealing with the treatment of such difficult cases which were eventually treated favorably. And, it should be noted that maintenance of centric stops and prevention of lateral interference were the important factors for a long term prognosis of occlusal stability.

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