It is not an over statement to say that the progress and developmaent in modern medicine, and especially dentistry, has been a history of the battle with pain. A great number of our predecessors have made tremendous efforts to alleviate this pain. Because people request measures for painless treatment beyond what is necessary, most dentists will prepare vital teeth for routine protine prosthetic treatment only after giving the patient anesthetic. However, because of this anesthetic it is impossible to acquire important information related to the patiet's threshold of pain, which is a physiological response. Therefore it is thought that instances often occur where too much tooth structure is cut away during preparation of the abutment tooth, and the pulp is adversely affected.
It is customary to use an air turbine handpiece (300, 000 to 400, 000 rpm) and local anesthetic when preparing vital teeth as abutments. However, in order to minimize the pain of treatment we always use a high-speed, friction grip, contra-angle handpiece with an electric micromotor (160, 000 to 200, 000 rpm) when preparing vital abutment teeth. I would like to report that because of this I have been able to carry out prosthetic treatment without the use of anesthetic for most cases.

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A simple method for measuring antero-posterior and bucco-lingual positions of an arbitrary point on a dental model mounted on an articulator has been developed and tested.
1. A measuring plate has been devised on which a dental model can be placed in coordinate to the reference planes erected vertically on its anterior and right and left portions. Using the jig plate and Digimatic caliper (Mitsutoyo Co., Tokyo, Japan), antero-posterior and bucco-lingual positions of an arbitrary point (for examples, cusp tip, fossa, etc.) on a dental model can be measured.
2. Using the jig, three fixed points on the same dental model were measured by three testees. The average standard deviations in the test, was 0.23 mm in the measurement of antero-posterior positions and 0.19 mm in the measurement of bucco-lingual positions.
3. By using the measuring plate devised in this study as a jig, antero-posterior and bucco-lingual positions of an arbitrary point on a dental model can be measured simply with accuracy of 4-5 times of the past method.

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The purpose of this study was to investigate the change of occlusal contact area, occlusal pressure and occlusal force through the growth. Dental Prescale^® were used for measurment.
All students were undergone dental examination and questionnaires about the episode of TMJ and orthodontics. The numbur of materials were 173 (male 85 and female 88, 12-18 years old) who had individual normal occlusion. The training to bite the sheet for measurment was done beforehand. The results were as follows ; Occlusal contact area and occlusal force were on the increase with growth. In male, the increasing of them were in harmony, but there was difference between the starts of increasing of them in female. Occlusal pressure were on the decrease with growth.
From these results, it suggests that there is sex difference between the style of teeth erupting and the growth of masticatory system included muscle.

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We placed full arch bite plates in the mandigble of four adult subjects who had no apparent problems with pronunciation or hearing, and raised thje vertihcal dimension of occlusion 4 and 8 mm. We then investigated the effect on the pronunciation of the one monosylable sounds/i//sa/∫a/ça//ta/ξa/ki//kja//t∫a /. We found that articulation was more difficult the greater the elvation of the vertical dimension, that there was not always a direct correlation between the clarity and degree of difficulty of articulation, and that there was a constant tendency of audio recognition as different sound regardless of the subject or the amonunt of elevation.

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The tapping and jaw movements path of ten edentulous subjects were clinically observed before and after treatment, which revealed that the oralmandibular components including TMJ hardly recovered sufficiently fine condition at a point of final denture set through provided temporary denture.
Therefore, the jaw position treatment of edentulous patients were not able to be terminated at the stage of final denture set, so that in the maintenance stage aftercare were required to be accomplished, which included occlusal face modification, artificial tooth exchange, rebase and relining.

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Recently, superior magnetic attachment has been developed and put to clinical use. In particular, the effectiveness is anticipated for spical bad teeth because lateral force is hard to act on maintenance teeth as for the magnetic attachment. When a condition of the abutment tooth is compar atively good, we reduce unrest of the denture by giving a supporting system and can utilize it positively. And, there is not function fall by abration. As for application of magnetic attachment which is used for a healthy teeth and spical bad teeth, it is thought when effective. Magnetic attachment has functionality which became stable, esthetics excelled.
In this study, we report it about a clinical case of removable bridge that magnetic attachment was applied as retainer.

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Subgingival caries, an existing faulty restoration, or a fractured tooth may not only affect the amount of coronal support but may also extend apically into connective tissue.
In these cases, surgical extension of the clinical crown by means of crown-lengthening procedure is imperative if apical overextension of the subsequent restoration is to be avoided. In other instances, for example an existing excessive subgingival caries or extensive radicular cyst, crown-lengthening procedure or surgical extrusion or a combination of these is indicated. This report we present a case, existence of subgingival caries and radicular cyst in the upper anterior portion.
It performed two surgical procedures, that a crown-lengthening procedure and a surgical extrusion for the crown-lengthening and the removal of radicular cyst prior to restoration. In consequently, this procedure can maintaining appropriate crown length, keeping biological width, and restore esthetically.

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The relationship of the maxilla and mandible is defined by the two parameters of horizontal and vertical relation. Although it is in general adequate to only consider the horizontal relationship when there are vertical stops on teeth, for the edentulous patient, who has no teeth, it is necessary to consider verticentirc, which is a mix of horizontal and vertical relationships. During conventional fabrication of full dentures, this has often been decided “in one shot” at what was called occlusal registration. This is because conventional fabrication methods for full dentures are linear techniques. However, when there is a problem with the maxillomandibular relationship of the existing dentures, prostheses fabricated in this way will often not feel comfortable and will require considerable adjustment time. Furthermore, remounting may be necessary for such reasons as problems arising in the joint.
The goal of the tentative denture method is to solve all of these problems beforehand and then to proceed with fabrication of the new denture. The tentative denture method is a technique that is a type of treatment denture that uses the existing prosthesis to determine the essential conditions for the new denture before the final impression. These conditions include modifications of the mucosa, determination of the form of the margins, and measurement of the maxillomandibular relationship.
I will explain how to determine verticentrrc using the tentative denture method.

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