Nichidai koku kagaku = Nihon University journal of oral science最新文献

TMJ clicking sound is a sign worth noticing as prodromal symptoms of TMJ dysfunction. Therefore, a solution of its characteristics is an important matter to grasp the diagnosis of stomatognathic function and progress of the disease. We try to systematize the procedure from picking-up TMJ sound to convertion of frequency and then investigate picking-up method and the measurement apparatus, because we need a quantitation of acoustical components of clicking sound to examine the influence of hearing ability due to TMJ dysfunction. The following were obtained: 1. Low frequency noise is reduced by using headgear with microphone located in a external ear. 2. We pick up continuous 30 TMJ sounds three times in separate days. The waveforms of each set are approximately similar. 3. Each peak frequency and pattern of power spectrum examined three times show high correspondence. 4. The range of maximum peak frequencies in all subjects are from 0 to 0.8 KHz.

In order to investigate the process to form diabetic-like condition by giving continuously excessive amount of sucrose, rats were maintained with purified water (Purified Water Group, PWG) and 10% sucrose solution (Sucrose Group, SG), as drinking solution, ad libitum for 5 months, and were subjected to the following experiments: 1) Serum glucose (BG) and insulin level (IRI) in sucrose tolerance test (STT) were measured periodically up to 24 hours after administration. 2) The number and affinity of insulin receptor on isolated hepatocytes from the rats of PWG and SG were also investigated. At the termination of the experiment, 5 months after the initiation, the BG and IRI levels in SG were significantly higher compared to those of PWG. In STT, SG showed reduced glucose tolerance and also high blood insulin level. The number of insulin receptor of isolated hepatocytes of SG was approximately 23% lower than that of PWG and the affinity of SG was slightly lower than that of PWG. These results suggest that continuous high BG and IRI levels are indicated in the rats given large amount of sucrose continuously. The number of insulin receptor of such rat was also reduced by down regulation, resulting in an insulin-resistance. These cause further high blood glucose level and abnormality in metabolism, to result in a prediabetic impaired glucose tolerance.

Bacteroides intermedius is one of the periodontal disease generative bacteria. Lipopolysaccharide preparation obtained from B. intermedius ATCC 25611 and ATCC 33563 strains was investigated as to Limulus activity observed with Pyrodic (endotoxin specific) reagent, and mitogenic activity in both normal and tolerant mice induced by Escherichia coli. Limulus activities of all LPS's were nearly similar to that of E. coli. LPS's preparation from B. intermedius were found to be strongly mitogenic for C3H/HeN mice spleen cells, whereas no LPS preparations were mitogenic for thymocytes of BALB/c mice. LPS-nonresponsive C3H/HeJ mice spleen cells were found to good mitogenic responses to LPS's from B. intermedius, as well as LPS from B. gingivalis 381 strain. Polymyxin B had remarkable inhibitory effect on the mitogenicity of LPS's from B. intermedius for C3H/HeN and C3H/HeJ mice spleen cells, also that activity of B. gingivalis LPS was inhibited by polymyxin B. The mitogenicity of the LPS from B. intermedius, as measured in C3H/HeJ mice spleen cells, was considerably resistant to the proteolytic effects of proteinase K.

Sixty one cases of selection error due to the esthetic factors of artificial tooth forms were investigated out of the 72 cases of selection error which were committed at the department of Prodosthontics in Nihon University school of dentistry at Matsudo for 17 years from 1971 to 1988. The following were the results of investigation, 1. The cases of S-type were changed to those of ST-type, which emphasized the Tapering type factors. 2. The those of ST-type were changed to those of SO-type and S-type which emphasized the Ovoid type factors and got rid of the Tapering type factors. 3. The those of SO-type were changed to those of STO-type which emphasized the Tapering type factors. 4. The those of T-type were changed to those of TO-type which emphasized the Ovoid type factors. 5. The those of O-type were changed to those of TO-type and STO-type which emphasized the Tapering and Square type factors. The regulations of re-selection showed the tendency of changing from single form to complex form, emphasizing the Tapering type factors.

The stress distributions in the laminate veneers under the two kinds of loadings are analyzed numerically by use of FEM in order to make clear the defects of various enamel preparations and Young's modulus of laminate shell materials in restored teeth. The analytical results are summarized as follows, 1) In both cases of two loading conditions under in this study, the stress distribution in restored teeth varied much with Young's modulus of laminate shell materials. 2) Especially in the case of thin enamel preparation in marginal light-chamber configuration, the higher tensile stress is obtained under the higher Young's modulus in the resin cement layer near the labio-gingival margin. 3) When the high load is applied normal to the incisal edge, considering each material strength, however what kind of laminate shell materials are used, the restored teeth is quite within the bounds of possibility for exploration in facio-gingival region or fracture in vicinity of loading points.

The purpose of this study was to examine and understand the nature of capsules consisted of fifty cases of unerupted wisdom teeth using radiological, pathological and immunohistochemical methods. Radiologically, the pericoronal space was measured with slide caliper and divided into three groups (-0.9 mm, 1.0-1.9 mm, 2.0mm). Pathologically, all specimens were examined by the routine paraffin method and were stained with hematoxylin.eosin and PAS-alcian blue pH 2.5 stainings. Immunohistochemically, PAP (peroxidase-antiperoxidase) method using various keratin antibodies, such as, anti-keratin K 528 (40-68 KD), anti-cytokeratin PKK 1 (40, 45, 52.5 KD), anti-cytokeratin PKK 2 (40, 46, 48, 54 KD), anti-keratin A 575 (56, 64 KD) and anti-cytokeratin high molecular weight (68 KD), and other various antibodies of anti-EMA, anti-IgA and anti-SC was used in order to study the nature of the epithelium of capsule of impacted teeth. The following results were obtained; 1. Radiologically, the width of the capsules was 1.6 mm in the average. Histopathologically, the inner surface of the capsule was covered with two types of epithelium which were composed of non-typical epithelium with cuboidal (basal layer) and columnar (superficial layer) cells, and typical stratified squamous epithelium. The epithelium lining was observed in 74% of all cases. Among the cases, cyst like structure was more often seen in the cases with typical squamous epithelial lining and with pericoronal space more than 1.0 mm width. 2. In the connective tissue's findings of capsules of impacted teeth, fibrosis was found in almost all the cases. Inflammatory and myxomatous changes were recognized in ca. half cases. Epithelial rest and calcification with dystrophy and epithelial product were observed in about one third of the cases. The epithelial proliferation in the capsule was also rarely seen in the specimens. 3. Immunohistochemically, keratins of 56 KD and 64 KD were identified in the superficial layer of non-typical epithelium and basal, intermediate and superficial layers of the typical squamous epithelium of the capsules of imparted teeth. Keratin of 68 KD was only observed in superficial layer of squamous epithelium. 4. Epithelial membrane antigen was positive in the intermediate and superficial layers of typical squamous cell epithelium. However, it was not seen in the non-typical epithelium of capsule of impacted teeth. 5. Immunoglobulin A and secretory component were negative in the epithelia of capsules.

The occurrence of maxillofacial bone fractures has gradually increased. These were two-hundred-fifty-nine cases of maxillofacial bone fractures from 1981 to 1988, in which fourteen cases were fractures of zygomatic bone and zygomatic arch. (The number of the fractures of zygomatic bone, zygomatic arch, zygomatic bone and arch, and zygomatic bone and mandibular bone were 5, 2, 4, and 3 cases, respectively). Pathognomonic symptoms were infra-orbital neuroparalysis, tristmus and recess of the buccal region. The incisional for open reduction were applied for the lateral brow, the lower eyelid, or intra-oral approach. U-shaped elevator was used for the reduction and miniplate and stainless wire were used for fixation.

Multiple forms of actin (alpha, beta, and gamma-actin) have been found in a variety of mammalian cell lines and tissues by the use of high resolution, two-dimensional gel electrophoresis. alpha-Actin is found only in differentiated muscle cells, and its synthesis is induced during myogenesis in culture, beta- and gamma-actin isotypes are the principal components of microfilaments, structures believed to be involved in cellular morphogenesis, motility, and mitosis. Recent studies have shown that mammalian actin mRNA levels are modulated in response to changes in cell shape and during cell differentiation in vitro. On the other hand, Kodama et al. isolated clone MC3T3-E1 cells from newborn mouse calvaria, which have retained the ability to produce and mineralize a bone-like ground substance after many serial passages. Thus clone is useful for studying osteoblast differentiation as well as the mechanism of calcification. It is demonstrated that bone cells assume a stellate morphology after some hormone treatment and these changes were clearly associated with altered reorganization of the microfillaments which resulted in an enhanced osteoblast phenotype. We have now examined the effect of culture day on expression of beta-actin gene in MC3T3-E1 cells and found that expression of beta-actin gene reduced with culture days. These alternative on the expression of actin gene suggest that beta-actin may be involved in bone remodeling in vivo.

Previous studies have shown that immunosuppressive effects are related to the pathogenicity of periodontopathic bacteria and the development of periodontal disease. We reported soluble sonic extracts (SE) from A. actinomycetemcomitans and B. intermedius had a strong immunosuppressive effect on primary response of anti-SRBC plaque forming cells. SE from A. actinomycetemcomitans inhibited the IgM----IgG isotype switching. The purpose of this study was to investigate the effect of SE on secondary immunoresponse. As a control, mice (C3H/HeN) were immunized with intraperitoneal injection of SRBC and complete Freund's adjuvant, and additional SRBC after 30 days. In order to study the effect of SE from A. actinomycetemcomitans on secondary response, four groups were prepared in this study. One group of C3H/HeN mice were injected SE intravenously before the primary immunization of SRBC. The other three groups were given SE at different time on secondary injection of SRBC and designated the pre-, post-, or simultaneous injection, respectively. Hemolytic plaque assay was performed and estimated anti-SRBC plaque forming cells in each immunoglobulin class and IgG subclass, on the 5th day after the secondary injection. The immunosuppressive effect was found in all the groups which we examined. The present study strongly suggests that periodontopathic bacteria have strong adjuvant activity, and long-term Actinobacillus infection accompanied by periodontal fluctuation in bacterial flora may induce aberration in the immune system. The suppressed immune system explain the explosive growth of bacteria tested in our investigation, resulting in the mixed or opportunistic infection by bacteria harbored in the gingival crevice.

The tooth structure of conical shaped incisor is observed with ground sections by light microscope. The Hunter-Schreger bands runs slightly convexed to the cervical from the dentino-enamel junction to the enamel surface. Enamel prisms arrange alternately and form almost arched type. Enamel spindles are observed remarkably. Many globular and interglobular structures are observed in the dentine. These structures are almost similar that of molar teeth expect some special types of enamel prisms. It is concluded that the conical shape did not cause of the reduced pattern of teeth structures.