Together with a diversification of the clinical dental needs of patients, there has been a tendency for simultaneous increases in the extent of the clinician's responsibilities in terms of both quality and quantity. In the field of clinical photography, for cases that had been handled with simple intraoral photographs in normal treatment, recently pictures are often taken of the face and lips including the teeth. In particular there has been a gradual increase in the need for facial photographs, and there has been a continual increase in the demand for pictures that provide a greater amount of information than has been acquired with conventional methods.
The actual clinical treatment of gnathology, which includes responsibility for the entire oral cavity, must be carried out by dealing with the acquisition of a variety of information associated with the patient's face. Consequently, acquisition of objective data requires high quality facial photographic methods. I will introduce a facial photographic method I devised that can simultaneously photograph the frontal, angular and lateral face of patients.

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I investigated how to reduce the time required for occlusal equilibration of prostheses in daily clinical practice by carrying out experiments on the precision of the opposing model. I measured variations in the dimensions of models that were fabricated when various conditions were changed, such as the water-to-powder ratio of the alginate impression material, the pressure applied to the impression tray during setting of the impression material, and the water-to-powder ratio of the plaster. In addition, I compared these values with those obtained for plaster models fabricated using the standard water-to-powder ratio, and investigated variations in products.
I concluded that precision was best when less water was mixed into the alginate impression material. Furthermore, it seems advantageous to reduce the amount of water when mixing the plaster since this increases the strength, while at the same time causing no problems with precision. For this reason, and because experiments have shown that different lot numbers of plaster require different water-to-powder ratios, I concluded that it is necessary to reconsider the concept of a standard water-to-powder ratio.

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Although there are various theories concerning the treatment of temporomandibular dysfunction, owing to the special nature of this disease, there is no single standard treatment method. Even though the effectiveness of the bite plane, which has been used for many years, is well known, it is not appropriate for all cases. In addition, it is common knowledge that relapses occur when its use is terminated.
Having many questions about these points, we have been carrying out research for several years. As a result, we arrived at the conclusion that favorable treatment results could not be attained without resolving the problem of the positional relationships of the temporomandibular joint region.
Conventional bite plane fabrication methods have been carried out without considering positional relationships of the temporomandibular joint. We concluded that the above problem may have arisen for this reason. We are making this report since we were able to attain good results with case where we incorporated a treatment plan taking into consideration these issues.

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Implants, and osseointegrated implants in particular, have today become an important technique in both fixed and removable prosthodontics. They have been highly acclaimed for their reliable occlusal support and excellent long term stability. However, the presence of an adequate amount of bone both vertically and horizontally in indispensable in achieving these results. Success with osseointegrated implants depends on accepting various restrictions with respect to the direction of placement.
These restrictions arise owing to the form of the upper structures, and include such factors as hygiene maintenance and improvement in esthetics. In addition, careful pre-operative planning is essential. In doing the pre-operative planning and postoperative evaluation for this clinical case, I considered how I could use the surgical guide splint during the implant surgery, and the possibilities of using CT (computed tomography), laminagraphy (including panoramic radiography), and intraoral radiographs, all of which are commonly used as important diagnostic data in daily practice.

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For the two measuring methods of occlusal vertical dimension using Dento-Profile and Willis techniques, four operators having different degrees of skill obtained measurements using these techniques from 20 subjects and these measurements were then compared. It was found that in either case of the techniques used, there were no substantial differences in measurements obtained by the skilled operators.
However, in case of Willis technique, the measurements taken by the other operators showed a considerably great difference from one another. In case of Dent-Profile technique, only a small difference was shown among all the measurements obtained. The above results indicate that the measurement using Dento-Profile technique may allow operators to secure almost the same clinical values, irrespective of the degrees of operators'skill.

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In recent years there has been a tendency towards an increase in adult malocclusion patients. Many of these cases are associated with factors complicating treatment, such as abnormalities in jaw function, esthetic demands of the patient, and problems with the periodontium, anchor teeth, mechanics, and restoration of the teeth.
Considering Loisella's report that orthodontic treatment is one factor inducing abnormalities in jaw function, it becomes imperative to devise a treatment plan using adequate data gathering and planning, and to monitor the postoperative course by regular examinations after completitn of the active orthodontic treatment. Therefore, in order to accurately diagnose abnormalities of the jaw at our clinic, we endeavor to make maximum utilization of both MRI and standardized TMJ radiographs, the SAM system developed by Slavicek, and questionnaires given at the initial examination.
Treatment of abnormalities in jaw function is most often carried out by the two step method of using a splint to modify the position of the mandible and improve symptoms, followed by reconstruction of the occlusion to stabilize and maintain the mandibular position. Although occlusal reconstruction is generally carried out by prosthetic methods, the use of orthodontic treatment has been brought forward as an effective modality. Reports have been presented by Roth, Sato, Ishikawa, Matsumoto, Tsuzuki and Machiya.
In this paper we report and discuss the case of an adult with an anterior open bite treated by orthodontic methods. We investigated anterior guidance, posterior support, and posterior guidance, examined radiographs of both temporomandibular joints, and investigated the periodontal tissues and locatinn of missing teeth.

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Although it is a widely accepted notion that craniomandibular disorders (CMD) and occlusal trauma do not arise simultaneously, occlusal trauma is seen in daily clinical treatment where teeth are in premature contact or have occlusal interferences. In addition, there are no small number of cases where CMD arises as a complication. This study carried out clinical investigations on cases where occlusal trauma was associated with CMD in order to better understand this situation.

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Localized abnormalities in the morphology of the alveolar ridge may arise from a cleft palate, advanced periodontal disease, trauma, and extractions associated with excessive force. As a result, the height and bucco-lingual width of the lost alveolar ridge may cause problems with establishment of the ideal relationship of the alveolar ridge and bridge pontic. Furthermore, loss of a portion of the alveolar ridge in the maxillary anterior region may cause problems not only with estetics, but also with hygiene and pronounciation. Therefore, various implansts and surgical graft procedures have been devised for such cases to restore the localized defect in the alveolar ridge to a more natural morphology.
Cohen described an alveolar ridge augmentation procedure for a localized defect that made use of hydroxyapatite (HA) . The method using subepithelial connective tissue graft reported by Langer and Calagna, and Garber and Rosenberg is very effective in correcting class I alveolar ridge defects. Abrams and Schart reported the rolling technique and the pedicle connective tissue graft that removed the epithelium.
This report discusses the surgery and postoperative course for three cases where alveolar ridde augmentation surgery was performed in a defect, the morphological abnormality in the alveolar ridge was restored, and the final prosthesis was compleated. HA was used in the first case to restore the alveolar ridge, a subepithelial connective tissue graft was employed for the second, and the rolling technique was used in the third case.

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The most important issue with the upper structure is the development and improvement of high precision components. With regard to selection of abutments, parts should be chosen that are appropriate for the distance between the implant and the gingival margin, the inclination of the adjacent teeth, and the distance between the implant and opposing teeth. The emergence profile must also be considered. Since the IMZ implant does not have a hex type connector with an antirotational mechanism, something to prevent rotation must be fixed to the abutment when a single implant is placed.
We report a case where we employed a trial and error technique to deal with these problems of a single implant.

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The craniomandibular system (CMS) is composed of the bones of the temporomandibular joint, cartilage, the articular disk, connective tissue behind the articular disk, and ligaments, in addition to the muscles associated with the masticatory system. The CMS functions in cooperation with the neuromuscular system and occlusion, carries out the functions of mastication, swallow, phonation and respiration, which are the principal functions of the masticatory organ.
While performing these activities it also carries out the task of preventing excessive retrusive and lateral deviations of the mandible, and positions the mandible in the correct anterior position. For example, because of the blood supply from an abundant vascular network, the connective tissue behind the joint, together with the lateral and collateral ligaments, prevent retrusive deviations of the mandibular condyle. The important function of positioning the mandible to the anterior is performed by the closing muscles, which include the superior head of lateral pterygoid muscle in conjunction with the mandibular condyle and articular disk, a portion of the anterior region of the temporalis muscle, and a portion of the deep head of the masseter muscle.
The mandibular condyle is prevented from excessive retrusion by guidance of the mandible to the anterior owing to interdigitation of the maxillary and mandibular teeth, as well as to their occlusal guidance. It appears that this functions to protect the organs of hearing and equilibrium, which are behind the temporomandibular joint. In addition, the harmonious relationship of the CMS and occlusion are thus able to function together to maintain balance by placing the mandible in a forward position.
It has been suggested that most of the functional disturbances in the temporomandibular joint result from imbalances in the CMS and occlusion. The basic issues are the function of occlusal guidance, whereby the mandibular condyle is positioned forward by the CMS, and the forced retrusion of the mandible caused by occlusion. In other words, a problem arises when the position of the mandible goes beyond the appropriate biological limits because of malocclusion. Furthermore, occlusal treatment must begin with determination of the physiological position of the mandible. However, it is not necessarily easy to determine a physiological mandibular position for each patient and devise a treatment plan. This is because the correct three-dimensional position must be found in order to reposititon the deviated mandible, which then must be placed in this precise position.
Furthermore, it is necessary to obtain the scientific data needed to establish this position. It is regrettable that in the past, measurement apparatuses were often not adequate to establish the appropriate mandibular position. One method for searching out the physiological position of the mandible is to determine its deviation (shown by the abnormal path of movement) by observing the path of movement of the condyle from its deviated position.
This reports presents a case where occlusal reconstruction was performed after determining the position of the mandible using the condylar path of movement obtained from a computerized axiograph.

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Advanced periodontal disease often compromises the tissues supporting the teeth, causing an increase in their mobility and movement. This causes a collapse of occlusion resulting from deterioration of occlusal support in the molar region and loss of anterior quidance, promoting a vicious cycle that leads to further collapse of the periodontal tissues.
In cases like this, periodontal and prosthetic treatment does not end with control of the inflammation, but also involves occlusal treatment that includes prosthetic restoration of missing teeth. In carrying out periodontal and prosthetic treatment, I feel it especially important to consider:
1. absolute control of inflammation, 2. establishment of the appropriate anterior guidance, and 3. placement of vertical stops in the molar region.
I would like to report this case which involved advanced periodontal disease and temporomandibular joint dysfunction resulting from occlusal collapse owing to missing teeth in the molar region. Although the treatment was extremely difficult for me and took a long time, I feel the results were rather successful.

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