前歯部に応用されるキャスト・コアーの形態に関する力学的研究

抄録

So as to research what form the cast core is, the two-dimensional photoelastic specimens were turned various into the survival degree of labial and lingual part of the tooth crown, were made and observed the stress distribution. At the same time, the dynamic comparisons between the one and two stage system were carried out.
As the results of these efforts, the following conclusions were obtained.
1. The existence in the lingual substance of the tooth crown was effective the control of the displacement for the load direction and the leap of dowel pin apex.
2. The about one-third existence in the lingual substance of the tooth crown was brought on the decrease of the stress distribution at lingual lower part around the dowel pin and the labial neck part around the tooth root.
3. In case of the clinical normal tooth form, the stress distribution in the abutment form, that was the cast core, being existed the labial one-third and lingual one-half part of the tooth crown are little each part. As it was exhibited the balanced distribution, consequently, it was said that these form was stable dynamically.
4. The stress distributions between the one and two stage system for the dowel crown prosthesis of the two plane root surface type were little differed.