The patient was 18 years old female with chief complaint of intermittent closed lock, sound and pain on opening movement on left temporomandibular joint (TMJ), especially rising. Though her maximum opening range of jaw opening was limited less than 27mm, she was able to normal opening when she was made eccentric jaw opening movement. In the MRI view in which both side TMJ were anterior disk displacement with reduction. Based on axiograph view, we considered that click-ing during mouth closing occurred in the mandibular position in which the displaced disc returned to the normal position on the chondyle, as we called therapeutic reference position (TRP), and per-formed therapy of using functional appliance. After the elimination of the clinical symptom is confirmed, as clicking, sound and pain during jaw movement, the occlusal reconstruction was per-formed by using the three dimensional control of tooth which multi-bracket method for TRP jointly with the functional appliance. The reconstructed occlusion was obtained with disappearance of all clinical symptoms passed after 2 years of post retention.
Therefore, it is possible that the therapy of occlusal reconstitution using the technique of orthodontics was an effective treatment for the anterior disc displacement with reduction case.

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It is known by experience that habitual mastication of chewing in one side of the jaw is thought partly as the cause of TMD (temporomandibular disorders) . The theory of biomechanics is tried to apply to some cases in clinical dentistry from the standpoint of habitual mastication. In this article the applied cases of biomechanics are reported on the result of treatment and the change of posture. In conclusion, it is suggested that there may be a correlation between mastication and posture.

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Under the physical function, occlusion, muscles and T.M.J. are bio-structurally connected one another. Cooperation during occlusion, muscles and T.M.J. is essential to establish comfortable and stable occlusion, and smooth mandible movement. In this treatise, using three dimensional comput-ed tomography (3D-CT), we have visualized condyle bone remodeling on the case, that mandibular deviation induced over loading on stomatognathic system and condyle bone erosion which was treated by occlusal reconstruction to C.R. position or physiologic mandibular position. This results suggested the effectiveness of normal loading for stomatognathic system.

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Various bite registration methods are used in general dental treatments. It is a crucial process to take out and reproduce centric relation records to the articulator without changing them from living bodies to diagnose and treat patients appropriately. The most important point is how reproducible the method is.
We experimented this time, to confirm the reproducibility of the gothic arch tracing method on the patients who have a dentulous ridge, since it is used for the general determination of the horizontal mandibular position. The five subjects are in their twenties through thirties, four females and one male. Two of the cases on the subjects are possibly suffering from temporomandibular disorder ; one case has already been treated for TMD ; one case has a type of open bite, and one case may have normal occlusion.
First, the cores were taken by the gothic arch tracing method on the apex and the tapping point, having the subjects bite lightly and heavily in each position. Also the records were taken by the improved chin-point method and the records after using and adjusting the occlusal splint for three weeks were taken by the same method. These cores and records were taken twice each.
Then the cores and records are confirmed with Denar's Centric Relator through the grooves of the split-cast. It must be determined whether or not the cores or records are identical, and whether the cores and records taken under the different circumstances and methods are identical as well. Besides, it was confirmed that the quantity and direction of the change of the position where the mandibular condyle was supposed to be, by using Denar's Vericheck Instrument.
The results are as follows : all 16 pairs by the gothic arch tracing method were not identical with each first and second core, except for one pair. But even that pair was not identical with any four records taken by the improved chin-point method. There was no definite correlation between any core's quantity and the direction of the change.
On the other hand, all of the centric relation records taken by the improved chin-point method were identical with each first and second record. That means each pair of records reproduced the same mandibular position. However, every record taken after using and adjusting the occlusal splint showed a different position from the initial records, in spite of the fact that they both were taken with the same method, except one subject who had been treated for temporomandibular disorder before. It can be thought that using and adjusting a splint makes masticatory muscles relax, and be able to get a more stable mandibular position. That means it is possible that the occlusal force occurs when the recording plate and stylus of the gothic arch tracer contact each other. Then those forces might have the mandibular condyle position change.
From the above, we can extract conclusions that in comparison with the improved chin-point method, the mandibular position taken by the gothic arch tracing method has a high chance of giving a different position from the stable mandibular condyle position, which raises questions on its reproducibility.

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[in Japanese]

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Prophylaxis of infection and control of forces are very important on prosthetic treatment, however, there is some technical difficulty in the case of the numerous missing teeth.
In the patient reported here, 14, 13, 12, 11, 21, 22, 27 missing teeth were treated with the cross-arch fixed bridge, and the good condition with the functional recovery and aesthetical improve has been kept for 18 years.

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The remount was a great need for the case of occlusal reconstruction, for example, the cases of extensive prosthetic treatment and periodontal retention. The remount was complex operation, and the error of remount coused a large deviation. To increase the value of remount, the objective and the operation procedure must be understanded. A method for avoid the error of remount in full mouth reconstruction were investigated.

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[in Japanese]

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[in Japanese]

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