Based on the results measured by the extraoral tracing device such as mechanical pantograph, it has been widely believed that sagittal lateral condylar path is longer in length and steeper in inclination than sagittal protrusive condylar path. The difference of the angle between sagittal lateral and protrusive condylar path has been known as Fischer's angle and its value is to be 5° in average.
In this study, the various data of sagittal condylar path inclinations measured electronically were recalibrated to the same horizontal reference plane, and compared. As the result, it was shown that the average value of Fischer's angle is -0.1°. Therefore, it is concluded that Fischer's angle is zero.
Fischer's angle is observed by mechanical pantograph measurement. Tracings are drawn on the recording table which is placed outside of the condyles. Thus, the inclinations of lateral condylar paths are drawn apparently longer than protrusive paths, although the both paths are not different in inclination. Through this study, it is concluded that the difference between lateral and protrusive condylar path inclinations is not necessary to reproduce on the articulator.

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The conventional twin-tables technique needed adjustment of two tables per patient. Since it is not cost effective, the author standardized a pair of tables with use of a standard typodent model. These were installed in a technical laboratory and used in clinical dental practice. As a result the prosthesis made with these revealed desirable posterior disocclusion.
Analysis of the amount of posterior disocclusion that is reproduced in patients and evaluation of experimental data of this method need to be made in the future.

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Average dimensions of the mandibular triangle were studied based on anatomical data in Japanese. The values of 110mm for the intercondylar distance which is the base length of the mandibular triangle, and 105mm for oblique side lengths of the triangle were obtained. In sagittal plane, supero-inferior distance from incisal point to transverse horizontal axis was 40mm, and antero-posterior distance from incisal point to transverse horizontal axis was 80mm.

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The interocclusal distances of the upper and lower study models mounted on a semi-adjustable articulator are in maximum Intercuspation were measured, using a bundle of registration strips. The average interocclusal distance was 0.10±0.10mm for the molars. Providing the diameter of man's hair is about 30 microns, then three hairs will pass through the clearance between upper and lower teeth in maximum intercuspation.

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Distannces between mesio-buccal cusp tips of the right and left molars were measured using a scale, on a maxillary study model. Comparing this results with the anatomical data reported by Sekikawa et al, fairly good coincidennce was obtained.

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Mathematical expressions for computing the amount of disocclusion from guiding factors of condylar and Incisal paths and also cusped inclination were derived, based upon the kinematic formulae for mandibular movement. Furthermore, providing measured data of disoclusion in place of cusped inclination, cusped inclination along protrusive and lateral cuspal path can also be computed.

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The conventional prosthetic procedures of Brånemark Implant System vary extensively, and are much more complicated than prosthetic procedures of conventional crowns, bridges and partial dentures. Thus it has been one of barriers to incorporate it into general clinical dentistry. The author fabricated an artificial crown with a gold sylinder, using cold cure resin, and developed a method to treat it in the same manner as natural abutments, by fixing it to a natural abutment in the mouth. This made it possible to reduce a number of patient's visits and technical work. The quite favorable result has been obtained since it was introduced into clinical practice. The author believes that development of the procedure to use an artificial crown for esthetic abutments is a task to accomplish in the future.

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