Patients with stomatognathic dysfunction were evaluated in terms of subjective symptoms, premature contact in the centric position, amount of mandibular movement, the maximum amount of opening, pulpation of the muscles and temporomandibular joint, arthrosound and Helkimo Index, and the following results were obtained:
1. Clicking was the most common subjective symptom, accounting for 34.5% of all the cases.
2. The dominant site of premature contact in the centric position was the left molar region.
3. The maximum average distances of protrusive movement were 8.6 mm±2.4 mm for men and 8.5 mm±3.3 mm for women. The maximum distances of right and left lateral movements averaged 7.9 mm±3.3 mm and 8.2 mm±2.9 mm for men and 7.2 mm±1.8 mm, respectively.
4. The maximum average amounts of opening were 47.6 mm±7.8 mm for men and 44.1 mm±5.7 mm for women.
5. The palpation of the muscles and temporomandibular joints revealed multiple tender pain points deep in the external and internal pterygoid and masseter muscles.
6. The exmination of arthrosound showed tender pain in the temporomandibular joint and muscles on the side demonstrating clicking.
7. Premature contact in the centric position had some correlation with pain points in the muscles, and also correlated with clicking
8. The calculations of Helkimo Index are considered effective for the judgement of stmatognathic dysfunction.

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This study showed requirements to construct well-adapted restorations with Ni-Cr casting alloys.
(1) The alloy should have a relatively low solid point below 1250°C
(2) The investment material should have small setting expansion and mostly should expand on heating with less deformation.
The low-fusing Ni-Cr alloys studied had a solid point as low as 1030°C, and demonstrated adaptability comparable to that of gold, silver and paradium alloys.

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Articulators were divided into the following three groups according to their adjustment capability for comparison.
Group 1: Articulators with balancing adjustment mechanism only.
Group 2: Articulators with balancing adjustment mechanism and changeable intercondylar distance mechanism.
Group 3: Articulators balancing and working adjustment mechanism and changeable intercondylar distance mechanism.
As far as the mandibular position of the balancing condyle is concerned, the articulators in all the groups can adjust it and completely reproduce the position of the human condyle. In the working side, however, adjustment range varies from group to group. When projecting to the sagittal plane, the articulators in the group 1 can express the condylar position only by a point. The articulators in the group 2 can express it by a line which is a continuity or points. The articulators in the group 3 have adjustment capability as a plane. In a three dimensional observation of this in connection with the first mandibular position from which lateral movement starts, the adjustment range of group 1 is a line which can be drawn horizontally, an area for the group 2 and a volume for the group 3, increasing adjustment capability a dimensional each. With an increase in adjustment capability, reproducibility naturally increases.
The adjustment of the condylar path is basically possible only on the balancing side of the articulators in the group 3. The curve of the lateral condylar path is more significant than that of the sagittal condylar path, taking the effects of tooth path on the condylar path into account.

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What can be a good guide for the initial evaluation, diagnosis and the subsequent treatment in practice? There may be 3 points: centric position, occlusal plane and vertical dimension constituting practical oclusion observed in daily practice.
Dental examinations of patients very often reveal discrepancy between the centric and intercuspal positions and premature contact. Sometimes, premature contact has been artificially created by the inserted restorations such as crowns and bridges.
It is clinically often seen that the occlusal plane has not been flat but has created concave and convex due to abrasion and attrition, loss and elongation of teeth, excessive contact between anterial teeth caused by reduced vertical dimension or the form of artificial restorations.
Vertical dimension has been occasionally lowered too much by abrasion and attrition, the disposition of the remaining teeth due to the loss of teeth or inproper height of occlusion of artificial restorations such as crowns and dentures. Peter K. Thomas stated thated that you should never change the vertical dimension and if not change, full mouth reconstruction would work well. In dental practice in Japan, we often see the case where vertical dimension is too low partially due to indifference to oral hygeine and oral function, and it is true that we cannot always do a good job without changing vertical dimension.
Based on these facts, the author believes that three points consisting of centric position, occlusal plane and veritical dimension are important reference points for evaluation, diagnosis and the subsequent treatment. He calls them“three cornerstones of occlusion”on practical basis.
If centric position, occlusal plane and vertical dimension are considered in working with the patient's oral cavity, not only treatment will go well but your efforts merit patient's trust.

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Favorable results were obtained by using Bioceram sapphire for the cases of oral rehabilitation. The suprastructure of implants was constracted with the emphasis placed on the following points:
1. Cuspid guidance was developed in occlusion.
2. The load bearing of the suprastructure of the implant was relieved by extremely narrowing the width of the occlusal surface.
3. A secure centric stop was developed in the individual tooth in the posterior region to develop occlusion in which the upper and lower teeth can readisclude during lateral movement. This prevents both implant and teeth from lateral forces.
4. A hygienic space adeequate for good oral hygiene was provided between the cervix of the implant and the adjacent tooth.

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