Provisional restoration is an important method when considering post treatment results and the predictability of post re-constructive therapy both biologically and functionally.
Provisional restoration are usually made with acrylic resin. However, metal provisional restorations are more effective as implant surgical stents and protect operated areas. They also act as occlusal atabilizers during the healing period.
This paper presents the clear advantage of metal provisional restorations over the usage of acrylic resin.

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The main objective is to keep which have trouble as healthy as possible for as long as possible. In severe cases when unhealthy teeth must be extracted to avoid further trouble, a complete denture will be applied. However, in circumstances when patients do not consent to removal denture application, the only alternative is to do concessive treatment.
This paper demonstrates the concepts and techniques to establish full mouth rehabilitation.

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Previous studies have reported on the effects of I-bar retained prostheses and splinted abutments in bilateral and unilateral distal extension cases with reduced periodontal support. Producing favorable stress redistributions in the abutments and surrounding tissues is difficult. Various retainer designs have been developed to address this issue. The purpose of this study was to investigate the stress redistribution in the abutments and surrounding tissues of three retainers device configurations based on the RPI system, Konus Krone system, and Bracing arm system using quasithree-dimensional photoelastic methods. Three composite photoelastic models were made of a mandible unilaterally edentulous distal to the right second premolars. Individual simulant materials were used for tooth structure, periodontal ligament, and alveolar bone. Three normal periodontal conditions of the right first and second premolar abutment teeth were considered, and three retainers were cast for the teeth. Unilateral partial dentures with various retainer designs, RPI system, Konus Krone system and Bracing arm system were made for the three models. Simulated vertical and lateral occlusal loads were applied to the dentures, and the stresses which developed in the supporting structures were monitored photoelastically.
Under comparable loading conditions, stress redistribution patterns in the abutments and surrounding tissues differed between the three systems, and The RPI system configurations showed the most uniform redistributions across loads directed in all five directions, while Konus Crone systems showed strongly stress redistribution for vertically, posteriorly, and buccally directed loads and Bracing arms configurations showed strongly stress redistribution for anteriorly and lingually directed loads. The results of this study demonstrated that the condition of vertical axis's angle, contact position and contact area of between abutments and retainers has considerable influence on favorable stress distribution.

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There are several intra-oral factors that possibly affect the bonding strength of the adhesives. These include saliva, blood, exudates from sulcus, humidity of expiration, and body temperature. Besides those, lip, cheek and tongue may disturb the adhesive procedure and result in bonding failure. In order to obtain reasonable bonding, it is necessary to control or eliminate the abovementioned factors.
Multi-purpose vacuum instrument, namely ZOO, was developed for adhesion without contamination. This serves as the equipment for suction, isolation, retraction, dehumidification, and mouth opener, as well.
In this report, the practical applications of the ZOO for the prosthetic procedures are explained.

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The resin modified glass ionomer cement was widely used for luting, filling and lining in the clinical situation.
The purpose of this study was to examine with the film thickness of the resin modified glass ionomer cement. 3 resin modified glass ionomer cement; Vitremer Luting Cement (VLC: 3M ESPE), Fuji Lute (FLE: GC), Fuji Luting (FLG: GC) and the conventional glass ionomer cement; Fuji I (FON: GC) were used in this study.
The specimens were prepared and measured following ISO 9917 and JIS T 6607. The data were measured immediately, 30 sec, 60 sec, 90 sec, 120 sec after mixing.
Mean of the film thickness were VLC: 8.1-10.4, FLE: 8.1-11.1, FLG: 6.1-12.8, FON: 10.9-18.3μm. The film thickness was varied with products of glass ionomer cement and setting time of load to specimen from 2-way analysis of variance.

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It treated to the patient who lost teeth by a severe periodontitis, and occlusal reconstruction. The treatment was phase I. periodontal therapy and periodontal surgery as the plaque control. In addition, occlusal function was recovered by provisional restoration. The final prosthesis was made konus teleskop denture expecting a sprinting effect of remaining teeth furthermore the plaque control and esthetic. It shifted to the maintenance every six months after it had finally prosthesis it, and passage was excellent. However, the vertical bone defects that a cause it in the occlusal trauma was admitted in mesial of the mandibuler right second incisor four years later the final prosthesis. Then, after the occlusal adjustment had been done, the flap surgery. Excellent passage is obtained through 12 years have passed since it finally prosthesis it now. It was recognized again that konus teleskop denture was effective as the final prosthesis of severe periodontal patient with losses of teeth through this case. Moreover, the importance of maintenance was recognized again.

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After partial resection of the gingiva surrounding the tooth using an electrosurgical scalpel, various temporary filling materials were applied, and the wound surface repair state was compared. In a clinical study, each temporary filling material was applied to the wound after resection using an electrosurgical scalpel, and the wound surface repair state after about 2 weeks was observed. In an experimental study, the used temporary filling materials were implanted into the rat body, and tissue reactions were observed by microscopy. In addition, the antimicrobial effects of the temporary filling materials on pathogens of periodontal disease were evaluated. The following results were obtained.
1. In a clinical study, the gingival state was the healthiest using Hy-bond, and relatively good using Neodyne α and Caviton. However, redness and inflammation in the wound surface were often observed using Neodyne α while gingival proliferation due to wear was sometimes observed using Caviton. Detachment often occurred using Copack and gingival inflammation or proliferation was relatively often observed using Stopping.
2. In the rat body, marked inflammatory reactions to Hy-bond and Neodyne a were observed. Stopping and Copack were completely inert foreign materials, inducing capsulation.
3. Hy-bond, Neodyne α, and Caviton had definite antimicrobial effects, while Stopping had no antimicrobial effects.

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We examined the effect of different inclinations of anterior incisal guidance on functional condylar movements (open/close, protrusion/retrusion, laterotrusion, anterior grinding, speaking, and mastication) and on the electromyographic (EMG) activity in the anterior part of the temporalis, the masseter, and the anterior belly of the diagastric muscle. The subject was a 37-year-old male whose upper four anterior teeth were planed to prepare them to receive a new prosthodontic appliance. The axiographic condylar movements showed that there were no significant changes in functional movements except in speaking and in masticating. For both of these functions, we observed a transverse displacement and reduced movement when the incisal guidance was steep. We analyzed a set of EMGs and observed that the activity of the anterior belly of the digastric muscle increased in the event incisal guidance was more than 15° steeper than the sagital condylar inclination (SCI) . Functional condylar movements and the EMG activity were relatively stable and the patient was comfortable when the incisal guidance was 10° steeper than the SCI. Based on these findings, we concluded that the incisal-guidance angle should be about 10° steeper than the SCI.

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Dental science has remarkable progress in recent years. There are new discoveries in basic research study, for example genetics and molecular biology. In clinical new techniques that anyone had not expected in the past, for example GTR, Implant and Auto tooth transplantation has consensus at present. However, application of the technique to patient in clinical is more difficult. This full mouth reconstruction case applied various techniques, for example orthodontic treatment, auto tooth transplantation and prosthodontic treatment, to severe periodontitis patient will be reported.

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In 1995, Takayama and Hobo produced a new prosthodontic procedure called the Twin-Stage Procedure, by utilizing Euler's equation of rigid body movement with three dimentions and six freedoms in kinematics of physics, and also utilizing basic data of mandibular movement, chosen from scientific literatures.
Since then, one of the authors, Itoh, has accumulated more than 400 cases utilizing the TwinStage Procedure during these ten years, As the result, by setting up the guidelines for diagnoses of occlusion utilizing the Twin-Stage Procedure, extensive and predicable diagnoses are enabled for diagnoses of occlusion, with high quality and broad range based on evidences.
The standard guidelines for diagnoses of occlusion, accumulated in this study, would be reported in the following, with the result that extensive and predicable diagnoses are has been enabled for diagnoses of occlusion, by utilizing the Twin-Stage Procedure.

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Prevalence of temporomandibular disorders (TMD) was surveyed within 2 weeks by questionnaire for all the patients of 183 dental clinics in Japan. Valid answer of 16, 748 was obtained and analyzed. Signs and symptoms of TMD were found in 13.6% of the patients with 9.9% for male and 17.3% for female (P<0.001) . Distribution of the prevalence of the patient with the TMD findings showed that female was greater than male in each age and smooth curve was exhibited as a whole with a peak at the later 30 years of age. The prevalence showed a tendency of remarkable increase from 11 years and gradual decrease from 50 years of age. Area difference was not recognized statistically.

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Biologic response by which problem institution was carried out in making a denture using the tissue conditioning using the tissue conditioner in Hydro cast method may produce change of occlusion, or it may not be generated. If it treats according to this when changeful, finally centric occlusion will be reached.
On the other hand, it is also known that the large range of palate will be embarrassed toward swallowing position if a transient stimulus is carried out. This is considered to be deeply concerned with Hydro cast method or Biologic denture method. If diagnostic denture is used, distinction of whether it is infraocclusion without temporomandibular disorders and whether to be temporomandibular disorders is possible. That is, when normal jaw movement is being carried out, it is changeless at diagnostic denture.
When it is infraocclusion without temporomandibular disorders, the same change is seen by right and left of the mandible. In temporomandibular disorders, vertical dimension is different in a molar part on either side, or change of cross bite is seen.
The above clinical diagnosis is possible.

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Bruxisim have been focused on as the mechanical forces that affected on the stomatognathic system; however the concept of habitual first stroke of mastication we proposed seemed to be more important than bruxism. In most of the clinical cases, the extent of power by the habitual first stroke of mastication is low level and may not be affected on the stomatognathic system, however once it fixed, it may become a destructive schock power to stomatognathic system, or once it accumulated over and over again, it may become accumulative and destructive power to stomatognathic system. In this report, we present the power by the habitual first stroke of mastication and give discussions on it.

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It is a well known fact that the use of osseointegrated dental implants reflect the latest line of thinking with regard to prosthetic restoration. Even if a fixed superstructure is preferred in most cases, an overdenture on the implant is accepted with several advantages. However, prosthetic management of the overdenture has two problems: firstly, the difference in the amount of tissue displacement between tooth and mucosa, and secondly, the presence of soft tissue under the denture base. The displacenent of implant is less than that of the tooth. Therefore, the difference is a crucial factor for the management of implant-retained overdenture.

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In patients with mandibular molar defects, implant therapy has increasingly been performed because of the discomfort of dentures and the occlusion load on residual teeth.
We performed implant therapy in a patient with mandibular unilateral free-end defects and obtained good results.
Patient: A 59-year-old male visited our hospital, requesting prosthetic therapy for mandibular defects on August 5, 2000. At the first consultation, there were defects in several maxillary and mandibular teeth, suggesting occlusal disintegration. In the residual teeth, chronic periodontitis in the entire jaw and caries in several teeth were observed. In addition, bruxo-facets suggesting bruxism were noted.
Treatment: Initial stage periodontal therapy was performed in parallel to splint therapy for the control of bruxism. After assessment, implants were placed in the mandibular molar defects. After a healing period of about 6 months, secondary operation was performed, and occlusal stability was attempted using a provisional prosthesis, which was followed by the final prosthesis.
The final prosthetic therapy for the defects was performed using a partial denture consisting of cast clasps and magnetic attachments in the maxilla and using implants in the mandible.
For spaces in the anterior teeth area, the course was observed because he did not desire treatment.
Results: Occlusal stability could be achieved, patient's discomfort was reduced, and functionally satisfactory results were obtained.

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This case report presents a technique with a surgical index for implant restoration in anterior region of maxilla. The patient was 19-year-old male who had lost right central incisor of maxilla by injury. In the first stage surgery, osteotomes were used to expand the labiolingual width of implant hole. The implant fixture was covered with autologous bone and guided bone regeneration membrane. In the second stage surgery of 6 months later, the membrane was removed, and surgical index was used to transfer the position of the fixture to working model. A temporary healing collar was completely covered with the flap to augment the height of soft tissue by guided soft tissue augmentation technique. In the third stage surgery, the resin provisional crown with proper emergence profile made on the working model was set on the fixture. After the provisional crown was adjusted for 3 months, final prosthesis was set. It was shown that the surgical index technique was useful in esthetic implant restoration.

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In this paper, it will be argued that white teeth and the process of tooth whitening are economically tradable goods, in the sense that they are objects of economic transactions. This situation derives from the fact that dentistry is becoming ‘consumerized’ and that white teeth are assigned certain cultural values, represent something to be identified, and thus become what consumers are willing to pay for. It will be shown that white teeth are a ‘sign’ in a semiological sense and thus the providers of whitening emphasizes cultural images of white teeth, such as purity, health, beauty, and youth, in advertisements of whitening. Hence, whitening can be viewed as the practice of creating meaning by using signs.

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[in Japanese]

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It is well known that the Cerec System is the only dental CAD/CAM system which completes the restorative treatment by chair side on the same day. As of the appearance of 3D software it made possible to display the abutment information in a three dimensional image. And also it has improved the functions such as the occlusal accuracy, the adjustment accuracy of contact point, the marginal accuracy by automatic margin detector and the realization of quadrant treatment.
With all these improved functions, we can do the restorative treatment with Gnathological occlusal accuracy without a working model or a model of antagonist. What we have practiced by hand was all virtualized and only made the final restoration.
It is clear that, in the near future, the Hi-tech computer will take a place of dental laboratory work which has always been represented as a filthy, tough and work at night. Tying up the CAD/CAM and Gnathology, it will make a contribution to new Gnathology. We seeing clearly that the new horizon of restorative treatment is coming now?

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