This paper investigates the functions and biomechanical properites of the viscerocranium from the perspective of phylogenic evolution. A new concept of the mechanical skeletal masticatory apparatus is proposed. Combines trilateral research in morphology (phylogeny-ontogeny), molecular genetics, and biomechanics, was reviewed in order to answer the question“What is the viscerocranium, i. e. face ?” For this purpose consideration of the basic construction of vertebrates and evolution in vertebrate was studied. For an insight into the basic skeletal construction in the viscerocranium, especially in the masticatory structure, the biological and biomechanical properties of the tooth were also investigated.
Establishment of basic construction of the vertebrates was carried out during neoteny (larval form evolution) of the hemicordata, which integrated the respiration, nutrients, and excretion system into only one tube of the gut. Through evolution of the vertebrate, mammals evolved after four kinds of vertebrate-revolution. These evolutional phenomena can be seen as revolutionary transformation of morphology in biomechanical responses to environmental changes. Through these evolutional transitions, various kinds of concerns develop between morphology and the function of organs in the human body from the standpoint of basement construction of the vertebrates. Through this study immune system was studied and a new concept for immunology as cytological digestion system was also proposed.

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Gnathology was defined by McCollum and Stuart (1920) as“the science that treats the biologics of the masticatory mechanism; that is, the morphology, anatomy, histology, physiology, pathology and therapeutics of the oral organ, especially the jaws and the teeth and the vital relations of this organ to the rest of the body.” (The Glossary of Occlusal Terms by International Academy of Gnathology, 1979) . On the other hand, the science of occlusion section of the Science Council of Japan, Liaison Committee for Sciences of Occlusion recently defined science of occlusion, tentatively, as“a field which united various sciences aiming 1) to study and clarify morphologically, functionally and kinematically the normal and not normal images and the aging changes of the stomatognathic system including the relation of this organ to the rest of the body, and 2) to apply the results to the diagnosis, therapy, reconstruction and esthetic reproduction.”Since these definitions are substantially the same, it indicates that the concept of Gnathology has penetrated into dentistry throughout this country.
However, it must be admitted that since Gnathology, in the process of its realization, had inclined excessively to precise mechanics, its standard procedures could not have applied to every clinical cases. Recently Hobo et al. proposed a new clinical procedure called“Twin-stage procedure”as a first step for the answer to the pending question in Gnathology. Continuously, the Japan Academy of Gnathology hammered out a scheme to expand scientific activities aiming“the elucidation on the relation to the occlusion of 1) the mandibular movement, 2) the maxillomandibular relationship, 3) the physiologic condition of the whole body, including muscular activities, 4) occlusal desease, including temporomandibular disorders, 5) implants, 6) dentures, 7) periodontal desease, 8) prosthodontics, 9) esthetics, and 10) various clinical procedures.” (J Japan Gnatho, 18 (3), 1997)
The footprints of Gnathology from the proposition by McCollum (1920) till today (1997) were briefly summarized.

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In clinical practice using implants, the management of residual teeth is sometimes a problem. In particular, in patients with a bone anchored full bridge, the method of allowing coexistence of the residual teeth and the implant is a problem.
There have been no studies on long-term observation of such cases. The management method for the residual teeth varies among operators and cases.
We observed serial changes in residual teeth connected with an implant prosthesis·bone anchored full bridge in 3 cases and evaluated the clinical usefulness of this method.

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In recent years, dental application of titanium has been extensively studied, and clinically applied. We developed and clinically used a conus type removable bridge with a magnetic attachment. In this method, occlusion is especially important. To provide an appropriate mode of occlusion in each case, functional diagnosis of occlusion was made in an early stage. An esthetical and functional occlusal plane was determined, and temporary occlusion was confirmed. In the articulator, face bow transfer, which allows reproduction of the face image, was performed. We report a patient in whom occlusal reconstruction was performed with titanium·magnet crowns (T. M crowns) by this procedure.

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The purpose of this study was to clarify the influence which was exerted on the absorbed edentate alveolar ridge volume by a pontic base form. We observed totally 189 bridges which had four different pontic base forms-Ridge lap type pontic, Saddle type pontic, Flat back pontic, and Sanitary pontic.
It clarified that a pontic base form influenced the absorbed dentate alveolar ridge volume in the process of years.
It suggested that some pontic base form were able to keep off surplus absorption on dentate alveolar ridge volume.

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In the treatment of occlusal disintegration accompanied by severe periodontal disease, a treatment plan based on a diagnosis considering the harmony of the teeth, periodontal tissue, temporoman-dibular joint, and the neuromuscular system and repeated re-consideration with progression of treatment are necessary. By these procedures, long-standing dental treatment effects can be obtained. In particular, when occlusal stability is considered, vertical stop is as important as anterior guidance.
Vertical stop is classified into the rigid tooth borne type, the implant type, the tissue borne plate denture type, and their combination. When possible, the tooth borne type vertical stop without movement subsidence that can be involved in the neuromuscular system is desirable.

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Production of impressions and working models in the production of prostheses for multiple teeth requires high level skills and includes many indefinite elements. In the removable and replaceable die type working model method using dowel pins, which is widely performed, impression of multiple teeth should be taken at a time. In the individual die method, impression taking of the dental arch model is generally very difficult compared with impression taking of the die. Therefore, we produce working models by the transfer coping method in daily practice for simultaneous prosthesis of multiple teeth. Epoxy resin (DIE·EPOXY^®: American Dental Supply, Inc.) is used as the die of the working model and a plaster (Zorock^®: Shimomura Plaster Co., Ltd.) as the dental arch model. The die is made removable, and prostheses are produced. The transfer coping method using composite materials does not require high level impression taking skills, and the working procedure at the clinic is simple. When prostheses for multiple teeth are produced, the burden on the patient such as the amount of dental anesthetics can be reduced. In addition, the die produced with epoxy resin with high accuracy and marginal strength can be used multiple times and can be readily detached from dental plaster in the production of a dental arch model. We describe here the procedure of the production of prostheses by the transfer method using composite materials in clinical cases.

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6 7 defect is morphologically defects of 2 teeth. Since they are two of the 28 teeth, patients often do not consider that loss of two teeth are serious. The oral cavity is very sensitive but is also highly adaptable. Therefore, patients may feel inconvenience immediately after loss of teeth but become accustom to this state soon and can eat as before without inconvenience.
This defect is morphologically a 2-teeth defect but functionally equal to a 4-teeth defect at _??_. The function and occlusal support of the molars are completely lost on one side. In mastication, presence of the place of mastication (food table) is of the first importance. In the absence of the molar food table on one side, masticatory movements lack right and left balance, inducing disturbance in mandibular movements. This causes mandibular deviation, markedly affecting mandibular movements during the non-functioning period.
We used a unilateral removable plate denture with a clasp in a patient with 6 7 defect and evaluated results. This denture adequately functioned for 5.5 years. This is a useful restoration method by which good results and patient's satisfaction are obtained.

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In the treatment of periodontal therapy, the stability of occlusions is essential. However, there has been little clarification regarding the role of the treatment of occlusion in the treatment of periodontal therapy for the following reason;
It is difficult to make a criteria for the diagnosis of the sites of occlusal trauma. Regarding the causes and conclusion of periodontal disease, the effect of occlusal trauma on these factors not clear. There has not been enough data acquired from long-term periods of observation to indicate the effectiveness of occlusal therapy the treatment of periodontal therapy.
Because of these facts, it is not clear how effective such treatment could be. Here, with some of date that has been acquired I would like to report on the significance of anterior guidance in long-term case studies of the treatment of occlusion.

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Recently, many epidemiological studies support that there is no special relation between occlusion and TMD (Temporomandibular Disorders) .
However, it is still controversial problem whether occlusion may cause TMD.
We encounted a case of TMD with malalignment.
A fifteen-year-old woman was examined to PDI Dental clinic with TMD pain on the left side, and disturbance of mouth opening. In the results of an examination at the occlusion, cuspid protected occlusion in lateral movement toward the right side was not established.
After occlusal splint treatment and minor tooth movement proceder, the TMD symptom was improved and had a good condition of TMD.
This paper outline, this case.

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Implantation, from the occulusive point of view, in which I dispose individual prosthesis of implant for 5 tooth.
The 56-year-old patient, had an extraction several months ago. Leaving the 5 tooth roots' destroyed.
The patient was recommended a bridge, however he was unwilling to mill teeth 4 and 6 healthy which were therefore, he visited my clinic hoping implants.
In conclusion, I selected IMZ^® Twinplus. As you know, the former IMZ^® implant conception has been absorbed in concentration on the strength which occurred between implant and the osteosurface. Then, IMZ^® Twinplus, keeping former conception, could be disposed for individual tooth. By improving abutment connector to make the notch inside an implant. Individual implant still needs an absorbing system, and it is important to have absolute concentration to prevent pay occlusive injury.
Especially, lateral traumatic injury. So adequate disposition is desired, to gain objective view of occlusive attachment area and strength. I used black silicone and visual analyzing system, for this operation.
Moreover, I highly occulusive completion of implant prosthesis system, using telescope abutment attained good adaptability to cement final prosthesis objective.

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First term treatment is most important process for disposing highly prosthesis. It is no exaggeration to say that this process decide whole treatment.
This time, I took final prosthesis disposition, assuring myself to preventing patient from occurring these annoyances, using three examinations (the buffer capacity of the saliva, the saliva secretion rete, and cariostad) on him (patient), who is in high risk of heavy periodontopathy and caries-activity at first term treatment.
I chose dental magnetic attachment for final prosthesis, considering to prevent inner mouth circumstances, periodontopathy and subordinatively-occurred caries of the patient.

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