An attempt was made of application of pressure detecting sheet “Prescale” into dental fields, with special reference to evaluation of vertical dimension by biting strength.
“Prescale” is easy to use and it is suitable for chair-side use. In a future more advanced study will be made to contribute to mechanical researches in prosthodontics.

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Recently the Pin-Restoration method is generally applied, with high esteem, in the clinical field. Here this Pin-Restoration method depens on some pins for sup- porting Fixed Partial Prosthesis, which, compared to other methods, does not require much preparation, and it is also valid from an aesthetic point of view.
This study employed a three-dimensional-phantom. The phantom had an anterior fixed pertial denture in which the upper right central incisor and canine were used as abutment and the lateral incisor as pontic. The principal object of this study was to explain the effect of the stress distribution on both abutments, in the case when the exterior forces-the occlusal forces-were applied at this phantom. The present author made experiments by applying three-dimensional photoelastic method on the phantom.
The load was set up on the central point of pontic incisal edge, and the stress distribution of abutment was examined.
As a result of these efforts the following conclusion was obtained.
1. At the central incisor the distribution of stress was examined; in the order of its magnitude: upper-distal-pinhole, lower-pinhole, and upper-mesial-pinhol.
2. At the canine; in the order of its magnitude; upper-mesial-pinhole, upper-distal-pinhole, and lower-pinhole.
3. Nearer to the load point, a comparision of upper-distal-pinhole at the central incisor with upper-mesial-pinhole at the canine indicated that the stress at the canine was greater.
4. Away from the load point a comparision of upper-mesial-pinhole at the central incisor with upper-distal-pinhole at the canine indicated that the stress at the canine was greater.
5. A comparision of each lower-pinhole at the central incisor with each lower-pinhole at the canine indicated that the stress at the central incisor was greater.
6. In case when the load was employed on the central position of pontic-incisal-edge, each of the pin-ledge abutment got mesial or distal and buccal or lingual moment.
7. Each pin set into central incisor and canine showed its own way of the effect of the stress applied.

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To investigate the mounting method of the cast to the articulator using inter occlusal record with a certain thickness for the aim to realize the intercuspal position, we studied the axis of habitual small opening and closing motion of the mandible, using 5 dentulous subjects who are normal in stomatognathic system.
We sought for position and displacement distance of “N” axis which is smallest moveing point when mandible takes habitual opening and closing motions, “H” axis which is the smallest moving point when mandible takes terminal hinge motion and “C” axis which is average condyle point.
Further more we analyzed mathematically anteropostero gap in anterior region based on positional difference between the axis used mounting and “N” axis. The results were as follows:
1.“N” axis existed 4.5 mm anterioly, 50.5 mm posterioly, 2.5 mm-5.2 mm inferioly from “C” axis. The position of “N” axis had a variety among subjects.
2. Displacement area of “N” axis in habitual small opening and closing motion of the mandible is the smallest of the other and is 1/1.4-1/27.0 compared with “C” axis and 1/1.3-1/48.6 compared with “H” axis.
3. Not exceeding 0.2mm displacement of “N” axis is so small that “N” axis is valuable as mounting axis of the cast to the articulator and also “N” axis is valuable compared with “H” axis.
4. Antero-postero gap in anterior region based on positional difference between the axis used mounting and “N” axis tend to be greater when “N” axis appear postero-inferior position and supro-anterior position from the articulator axis by mathematical analysis.
5. Mathematical analysis shows farly large error when mounting without true mandibular opening and closing axis, therefore using “N” axis lead desirable result.

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