Purpose: The aim of the current study was to reveal the stress behavior under simulated mucosa exposed to dentures fitted with resilient denture liners as well as to explain, at least in part, the cause of the prolonged occluding phase observed in edentulous patients who wear complete dentures fitted with resilient denture liners.
Materials and Methods: A cylindrical metal rod weighing 100 g was dropped perpendicularly onto the samples from a height of 3 cm. The samples were placed on simulated mucosa constructed from a silicone impression material; they were 1.5 mm-thick and contained a pressure sensor of diameter 2 mm in their lower regions. Samples of diameter 6 mm and thickness 2 mm were prepared from conventional denture base resin and fitted with 2-mm-thick resilient denture liners. A total of one acrylic-based (PSR) and two silicone-based (SLT and SLMS) resilient denture liners were used. Output signals were transmitted by the stress sensor through a sensor interface to a personal computer. The signals were sampled at a rate of 1 kHz. The following three parameters were used for assessing the observed stress behavior: maximum stress, time required to reach maximum stress, and stress-propagation speed. MANOVA, ANOVA, and Bonferroni post hoc test were used for statistical analysis (α = 0.05).
Results: The relationships of the magnitudes of the abovementioned parameters were as follows: maximum stress, control: PSR ⟩ SLT ⟩ SLMS; time required to reach maximum stress: SLT, SLMS ⟩ control, PSR; and stress-propagation speed: control, PSR ⟩ SLT, SLMS.
Conclusion: On being subjected to the shock load, the silicone-based resilient denture liners showed lower maximum stress, took longer to reach maximum stress, and exhibited slower stress-propagation speeds compared to the findings obtained using the acrylic-based resilient denture liners.

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Purpose: A new “fiber post” material is expected to be effective against root fracture after restoring endodontically treated teeth. However, there have been very few studies on post-and-cores for abutment teeth of fixed bridges. The purpose of this study was to clarify the usefulness of the fiber posts and composite resin cores for abutment teeth of cantilever fixed bridges.
Materials and Methods: Three post-and-core methods (prefabricated metal post and composite resin cores, fiber posts and composite resin cores, and composite resin filling for post and cores), and three loading conditions (direct 45°, indirect 0°, indirect 45° to the tooth axis) were examined to determine the initial and maximum failure loads and mode of failure using 90 bovine teeth to simulate the human lower premolar.
Results: Indirect 0° and 45° loading were strong enough to reduce the failure load to one-quarter to one-half of direct 45° loading. The fiber posts and composite resin cores indicated almost the same initial and maximum failure loads as the prefabricated metal post and composite resin cores, and significantly higher maximum failure load than the composite resin filling for post and cores.
Conclusion: The fiber posts and composite resin cores indicated almost the same failure load as the prefabricated metal post and composite resin cores but the failure load reduced remarkably under the condition of abutment teeth of cantilever fixed bridges. Furthermore, the post and core method with fiber posts could not prevent root fracture of the abutment teeth.

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Purpose: Purpose: To compare and investigate whether habitual snoring and/or bruxism during sleep manifest themselves in the morphological characteristics of the face.
Methods: The presence of snoring was determined and classified using questionnaire results and data recordings of respiratory sounds which were recorded and heard during sleep at night, and the presence of bruxism was determined and classified using observations of punched holes and grinding traces on a splint worn during sleep at night along with reference to oral findings (presence of tooth attrition, bone tubers, and wedge-shaped defects in the cervical area). In addition, for the filming and recording of faces, a non-contact three-dimensional measuring device was used to compile three-dimensional facial images, which were analyzed later.
Results: 1. Among the 36 subjects, 5 showed both snoring and bruxism, 8 showed only snoring, and 6 showed only bruxism. 2. The morphological facial differences according to the presence or absence of snoring showed characteristic morphologies near the outline at the lower extent of the faces. 3. The morphological facial differences according to the presence or absence of bruxism showed characteristic morphologies near the zygomatic arch, which is the beginning of the masseter near the outline of the side of the face in the upper and mid facial regions.
Conclusion: The subjects who showed habitual snoring and bruxism during sleep had characteristic facial morphologies, suggesting that the 3-dimensional characteristics of the soft maxillofacial tissues may provide a helpful indication at the time of diagnosis.

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Patient: A 62-year-old edentulous female patient visited with a chief complaint of poor retention of lower complete denture during singing. A lower complete denture was fabricated applying flange technique to improve retention and stability during functional movement.
Discussion: A chief complaint of poor retention and stability of the lower denture during singing was improved by applying flange technique. It seemed that a use of composite denture teeth with high wear resistance contributed to keep occlusal condition for long time in this case.
Conclusion: In this case, a lower complete denture was improved retention and stability during singing by applying flange technique. 12 years have passsed without problems.

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Purpose: Patient: The patient is a male with a diagnosis of a fibrosarcoma of the left maxilla at age 52. As a result of ablative surgeries, the patient lost his left eye, orbital cavity contents, and left-side maxilla. Maxillofacial prosthetic treatments included an implant/magnet-retained orbital prosthesis for his left facial esthetics.
Discussion: The implant/magnet-retained orbital prosthesis offered the patient satisfactions because of not only esthetic improvement of the left-side orbital defect but also ease of placement and removal of the prosthesis.
Conclusion: Implants and magnet attachments are of great benefit in providing retention, support, and stability for the orbital prosthesis of the patient without enough residual soft tissue around the defect.

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Patient: The patient was 28 years old. She visited the Department of Prosthodontics and Oral Rehabilitaion, Osaka University Dental Hospital with complains of difficulty during mastication and esthetic dissatisfaction. In a traffic accident, maxillary and mandibular bone was fractured and maxillary and mandibular anterior teeth were missed. In this case, removable partial denture was fabricated for defect of maxillary and mandibular anterior teeth.
Discussion: It is guessed that the reason of good following is to use the Schiene made assuming occlusion before injured.
Conclusion: The patient was followed for about 4 years after treatment with no complications and she was very satisfied with mastication and esthetics.

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Patient: A 52-year-old woman presented with esthetic problems in the anterior tooth region. The patient was diagnosed with masticatory, speech and esthetic disorders due to anterior diastemata. Ceramic laminate veneers were prepared for the maxillary and mandibular anterior teeth.
Discussion: The maxillary and mandibular anterior tooth laminate veneers functioned favorably for about 12 and 7 years, respectively. The long-term stability of the maxillary and mandibular anterior tooth veneers could be attributed to the maintenance of an appropriate occlusal relationship and the use of adhesive resin cement.
Conclusion: The results suggest that the use of maxillary and mandibular anterior tooth laminate veneers is useful for patients with anterior diastema.

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Patients: A 51-years-old female patient missing right mandibular molars and some incisors in maxilla had been treated. Both the anterior guidance and the occlusal support seemed to lack of reliability. Following the diagnosis this patient needed almost full-mouse procedure, recover of occlusal support by dental implant was performed with priority. Then, anterior guidance was reconstructed using provisional restoration and custom-incisal table.
Discussion: Suitable reconstruction of the anterior guidance and achievement of precise disocclusion could accomplish therefore occlusal support had recovered at earlier stage.
Conclusion: After establishment of occlusal support in molar region, utilizing provisional restoration to search an adequate anterior guidance and to transfer information of guidance to the final restoration by custom-incisal table seemed one of the available techniques for the case of restoration including anterior guidance.

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Patient: A 68-year-old women came to our department with the chief complain of oral general malaise. The treatment did general prosthetic treatment and did a test result of volume of saliva test was done in refe-rence more. The symptom was improved after having set a provisional bridge. In the four years after completion of the final prosthetics, and the posttreatment course is excellent conditions without oral general malaise.
Discussion: As for improving occlusion adequately, enough jaw movement is enabled. As for it being possible for appropriate jawmovement, the volume of saliva enlarges to be able to add irritation for salivary gland. Thus, it seems that appropriate jaw movement and enough the volume of saliva by improved unidentified complaint.
Conclusion: The prosthesis which harmonized with jaw movement does not improve satisfaction of the patient and is useful for improvement of oral general malaise. The volume of saliva was taken in as an examination item at the time of a treatment. A index and likelihood of prosthetic treatment were suggestd the volume of saliva test.

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Patient: The patient was a female age 63 who visited with the chief complaints of masticatory disturbance. The patient was diagnosed with masticatory dysfunction due to coronal decay; the patient was promptly fit with treatment dentures. The treatment denture was easy to float and also induced a sensation of vomiting reflex. A denture with a resin base to provide magnetic attachment was similarly selected for the lower. A subjective assessment was executed by each process for the function of satisfaction and mastication.
Discussion: Vomiting reflex was intensified by irritation due to looseness of the denture, and fitting of a lower denture to provide magnetic attachment was able to resolve this sensation.
Conclusion: Use of stable retention produced by magnetic attachment provided a good sense of fit even in a patient in whom denture treatment induced a sensation of vomiting reflex.

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Patient: A 54-year-old female patient had a odontogenic maxillary protrusion with moderate chronic periodontitis. Her chief complaint was the esthetic problem of maxillary anterior teeth. A bite plate with orthodontic elastic bands was used for tipping maxillary anterior teeth. After orthodontic treatment, an adhesive splint was applied to mandibular teeth as a transitional treatment. During transitional period, temporomandibular joints and esthetic conditions were observed to make sure of no side effects of the occlusal reconstruction and the result of the orthodontic treatment. Then the final prosthodontic treatments were delivered on mandibular posterior and maxillary anterior teeth.
Discussion: The esthetic prosthodontic treatment made fine outcome and the patient was satisfied with the functional and esthetic results. The maintenance were continued for 4 years, and the conditions were stable.
Conclusion: The fixed prostodontic treatment including orthodontic and periodontic treatments could satisfy the functional and esthetic expectations of this patient sufficiently.

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Patient: Patient: A 77-year-old female patient complained her lower complete denture, which had been wearing for three years, was unstable and she hoped to fabricate new dentures. As severe resorption of alveolar bone, I fabricated upper and lower complete dentures with flange technique.
Discussion: Although old lower denture was well-fitting and had no problem about occlusion, several denture ulcers were seen on the mucous membrane of mandibular ridge. As the reason of this problem was thought that denture displacement which was occurred by the oral muscle pressure when function, new dentures were used a functional impression technique to keep the stability of new dentures by pressure from muscle activities around dentures.
Conclusion: Because of taking denture space, the problems of unstability and denture ulcer had improved.

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Patient: The patient was a 69-year-old woman who presented with a chief complaint of masticatory dysfunction due to the detachment of implant supported fixed denture in mandible. As a treatment, severely carious teeth were extracted while remaining tooth and implants were restored and temporary restoration was placed. The follow up period showed patient's satisfaction over function. Finally, a removable type of over-denture was made to support and care the remaining implants while restoring function.
Discussion: Follow up period of 4.5 years after removable over-denture treatment has shown good masticatory function with no peri-implantitis.
Conclusion: In this case of secondary treatment after implants fixation, over-denture was effective and compatable to intra oral environment thus increasing patient's QOL.

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