Tsurumi shigaku. Tsurumi University dental journal最新文献

{"title":"[Basic studies on hard direct reline resins. Part 1. Adhesive strength].","authors":"C Ohkubo,&nbsp;Y Takayama,&nbsp;E Ohkubo,&nbsp;A Nakamura,&nbsp;Y Kawai,&nbsp;H Murakami,&nbsp;T Miyata,&nbsp;J Obana","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Direct relining methods has come to occupy an important position in removable denture prosthodontics. The purpose of this study was to investigate the effect of various experimental conditions on the adhesive strength of hard direct reline resins to denture base resin. The experimental conditions were as follows: 1) immersion time of denture base resin before relining, 2) amount of load at relining, 3) roughness of adhesive surface, 4) immersion time of relined resin. The following results were obtained: 1. The adhesive strength of Rebaron was the highest, followed by that of TRIAD and KOOLiner. 2. The immersion times of denture base resin did not appreciably affect the adhesive strength. 3. With the rougher adhesive surface, Rebaron and KOOLiner showed a tendency to increase adhesive strength. 4. The adhesive strength was not appreciably affected by load. 5. We did not find a definitive correlation between adhesive strength and immersion times of relined resin.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"131-8"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13768621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[The morphological study of experimental caries produced in rat molars].","authors":"R Tanaka","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Since there is some disagreement over the validity of using the rat for various experiments of relevance to dental caries in the human. The process of carious formation in the lower first and second molars of the rat was observed histologically. 120 new born Wistar rats were divided into two groups, one on a carious diet and the other on a standard diet. Both control and experimental animals were killed at preselected intervals namely 1 week, 4 weeks and 7 weeks after weaning. The maxillary and mandibular tooth bearing segments were removed and fixed in glutaraldehyde and osmium. After clinical examination and assessment of the caries status made with the aid of a binocular microscope, the material was sectioned without decalcification and prepared for light, electron, or microradiogram. From the results it was concluded that, 1. The caries process in the rat is extremely rapid much faster than in the human for example complete breakdown of the crown occurs within 28 days of weaning. 2. Frequently destruction of the dentin occurs before mineral loss is detectable in the enamel. 3. Rarely are any of the characteristic features of the early human caries lesion, such as the surface zone, body of the lesion, the dark zone and the translucent zone, to be found. 4. When a surface zone is visible, the dentine is usually in an advanced state of destruction. 5. The histopathology of rat caries does not therefore follow the same pattern as in the human. It is deduced that the reasons for these differences with the human lesion are due to. a) Rat molar enamel is extremely thin being only 100 microns in the thickest part of the fissure enamel whereas it is 2.5mm in the human. b) Rat molar enamel has a lower mineral density than the outer two thirds of human enamel, and is even lower (2.74) than the average value for the inner layer deciduous human enamel. (2.85-2.92) (Weidmann, et al., 1967) c) Rat enamel is extremely porous allowing easy diffusion of fluid and dyes. d) This porosity may be related to incomplete maturation of the enamel when the teeth erupt.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"183-99"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13768625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[An effect of the clenching speed on the method of calculating the biting force of patients by using electromyography].","authors":"H Hirata","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The recovery of the masticatory function in patients with dentures was assessed by several indices such as masticatory efficiency, maximal biting force and electromyographic analysis. We have attempted to develop a new method of calculating the biting force of edentulous patients by using electromyography. The method has almost been established, but, depending on the clenching speed, there is a certain difference between the estimates obtained from this method and the biting force obtained from a force transducer. The purpose of this study is to clarify the effect of the clenching speed on the method of calculating the biting force by using electromyography. In 9 healthy subjects with normal dentitions, biting force and electromyograms were recorded simultaneously under 3 different clenching speed conditions. After the recording, the relation between the biting force and integrated electromyography was compared thoroughly. The effect of the clenching speed on the method of calculating the biting force by using electromyography was also investigated. The following results and conclusions were obtained: 1. At a slow clenching speed, a linear relation between the biting force and integrated electromyography was found. 2. At a medium clenching speed, the relation showed a slightly upward curvature as the biting force was increased and a slightly downward curvature as it was decreased. 3. At a fast clenching speed, the relation between the biting force and integrated electromyography showed an upward curvature as the biting force was increased, and a downward curvature as it was decreased. 4. At the slow and medium clenching speeds the estimates obtained from this method approximated the biting forces obtained from a force transducer. 5. At the fast clenching speed, the tendency was found that the estimates obtained from this method were higher than the biting force obtained from a force transducer. 6. When realizing this tendency, the method of calculating the biting force by using electromyography can be said to be clinically effective.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"211-33"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13768627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Ultrastructural study on the developmental process of the dentin bridge following direct capping using hydroxyapatite ceramic].","authors":"J Noguchi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Hydroxyapatite ceramics (HAP), which have been used in the endodontics or periodontics because of their bioafinitive characteristics, were applied directly as the capping of the wound surface after the experimental exposure of pulp in versional teeth to be extracted on orthodontics ground. In order to investigate the developmental process of dentine bridge induced by HAP capping, the pulp was studied ultrastructurally, 1, 3, 6 months after the treatment. One month after the capping, the multi-nuclear giant cells being rich in mitochondria and lysosomes were in contact with the HAP granules directly by extending their projections into the granules, which appeared to absorb the HAP granules. At the same time, the osteoblast-like cells with remarked rough endoplasmic reticulum (rER) were also observed just behind the giant cells. Only a few matrix vesicles and fibers were recognized around these osteoblastic cells. The HAP granules embeded in the pulp for 3 months were surrounded by fine matrix fibers which seemed to be produced by adjacent osteoblastic cells. The surrounding of these cells were filled with abundant matrix vesicles and collagen fibers, which would show the production of osteodentin matrix and the minerilization were active in this region. Six months after the treatment, the osteodentin matrix in upper dentin bridge became compact; matrix fiber surrounding the HAP granules became thick and a part of fibers inserted into the granules, which should mean that the HAP granules had bonded to the osteodentin matrix. In the deeper region of the dentin bridge, tubular dentin was formed newly. Both osteodentin and tubular dentin fused tightly without any organelles in the boader between them. The covering of hard tissue of dentin bridge then bonded to primary and reparative dentin closed the wound surface to protect the inner pulp.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"63-86"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13703620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Histogenesis of Sea Bream (Pagrus major) enameloid].","authors":"S Shimoda","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The enameloid matrix consists of a collagenous matrix, and non collagenous proteins. Mature enameloid is highly mineralised similarly to mammalian enamel a large amount of the protein being removed. This is in contrast with bone, cementum, and dentin, where a large amount of collagen remains in the completed tissue. From the results of a biochemical study it has been suggested that the decrease of a major part of both the collagenous protein in developing enameloid is brought about by proteolytic enzymes (Kawasaki et al. 1987). However, histological and histochemical observations were not made at that time. In this study fourty-five live specimens of Sea Bream (Pagrus major) were used for histological and histochemical observations. Four undemineralised serial cryostat sections were obtained from each tooth garm and the developing enameloid matrix was observed ultrastructurally. The results of this study, show that the proteolytic enzyme activity which could not be detected in the enameloid formative stage, but was demonstrable after mineralisation had spread across the thickness of the matrix. Further more, the stage at which the proteolytic enzyme could be obtained was related to the stage of ALPase activity found in the dental epithelial cells.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"267-84"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13767743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Electron microscopic study of periodontal tissues in the pressure side by intermittent forces].","authors":"T Kazama","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The intermittent forces (10g and 30g) were applied to the upper right first molars of mature Wistar rats to move them lingually for 1, 5 and 9 days with wire springs. The periodontal tissues in the pressure side were investigated light/electron-microscopically and cytochemically (localization of acid phosphatase activity). The periodontal tissues in the pressure side divided into the following three areas were observed. The area I: The area of hyalinized tissues. The area II: The area situated within 100 microns from the end of hyalinized tissues. The area III: The area situated within 100 microns from the border of area II. The following results were obtained. I Tooth movement Experimental teeth applied with 30 g were moved much more than those applied with 10g. II Light microscopic findings 1) The narrowness of the periodontal space in the area I was not observed remarkably on 1 and 5 day experiment of 10g and 1 day experiment of 30g, though hyalinized tissues had appeared in them. 2) Semi-hyalinized tissues observed in some parts of area II degenerated into hyalinized tissues during the experimental periods. 3) Direct resorption of alveolar bone by osteoclasts was seen initially in the area III on 5 day experiment of 10g and 1 day experiment of 30g. III Electron microscopic findings 1) The hyalinized tissues (area I) and semi-hyalinized tissues (some parts of area II) were characterized to contain only a few necrotic cells and cell debris. The localization of Acpase activity could not be seen in these cells and cell debris. 2) Fibroblasts in the area II and III showed various appearances; autophagy, heterophagy of collagen fibrils, fusion with other fibroblasts and cell degeneration. And the localization of Acpase-activity was observed remarkably in lysosomes, secondary lysosomes and Golgi apparatus. A few macrophages were observed in the area II and III, but the other inflammatory cells and foreign body giant cells could not be seen. 3) On the other hand, active and inactive osteoclasts were seen on the bone surface in both area II and area III.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"87-108"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13767746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[A dynamic fitness test and a new method to measure the thickness of film using the digital subtraction system of X-ray photographic density].","authors":"S Hanatani","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>It is impossible to show the dynamic fitness conditions of a denture base using White Silicone or other fitness test materials. In the present paper, materials and the measuring method for the dynamic fitness test were investigated. In order to choose the suitable materials for the dynamic fitness test, various kinds of ready made materials, such as wax or dynamic impression materials, were examined by load test and investigated the change on standing of flow character. EXPERIMENTAL WAX was made for dynamic fitness test, and was examined by load test and clinical test. EXPERIMENTAL WAX consists of DISCLOSING WAX (KERR), as a basic material, and the contrast medium. Extending the system of the conventional measuring method for White Silicone, DIGITAL SUBTRACTION SYSTEM (DSS) was developed as a new method of quantitative analysis for the thickness of wax film. In this system, thickness of wax film is measured from the X-ray photographic density and it's digital subtraction management. Accuracy of this system was also investigated. The summary of results is shown below. 1. It became evident that ready made materials had no useful characters for the dynamic fitness test. 2. EXPERIMENTAL WAX showed similar load effects with White Silicone when the load was 5 or 10kg. 3. Dynamic fitness and the mobility of the denture base during function were able to be shown by EXPERIMENTAL WAX, but it's operation was more complicated than White Silicone. 4. DIGITAL SUBTRACTION SYSTEM (DSS), a new method of quantitative analysis for the thickness of wax film, was developed. 5. Resolving power and measuring range of DSS were effected by quantity of subtraction. 6. DSS is not only useful to measure the thickness of EXPERIMENTAL WAX, but also has wide applications.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"119-30"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13837738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Immunoglobulins in periapical lesion with special reference to qualitative and quantitative analysis of IgG].","authors":"H Yamamoto","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Immunoglobulins in periapical lesions (including 34 radicular cysts and 11 radicular granulomas) were investigated through extracts of the lesions and cystic fluids. The extracts of dental sacs and sera were used as a control. For a qualitative analysis, the immunoglobulins (especially IgG) of each sample were investigated by agarose gel electrophoresis and agarose gel isoelectric focusing. For quantitative analysis, single radial immunodiffusion was employed for determining the concentration of IgG, IgG subclasses, IgA and IgM in the extracts, cystic fluids and autologous sera, also IgE in cystic fluids. In agarose gel electrophoresis, homogeneous bands that were regarded as monoclonal or oligoclonal patterns in gamma region were identified with IgG by immunofixation. These bands were detected in 65% of the radicular cysts, 73% of the radicular cysts obtained cystic fluid, and 73% of the radicular granulomas, but were not detected in any of the autologous sera and dental sacs. In cases that these homogeneous bands were found in extract of cyst, the same bands were found in fluid of same radicular cyst. These results strongly suggested that a part of IgG in periapical lesions was locally produced. By agarose gel isoelectric focusing, immunoglobulins in the extract, cystic fluid and serum were investigated. Many clearly detectable bands were found in extracts of periapical lesions and cystic fluids in the range of pH 6-9 and identified with IgG by immunofixation. These findings revealed restricted heterogeneity of IgG. These IgG bands were found randomly in the range of pH 6-9 and no specific inclination of arrangement. These results suggested that IgG in periapical lesions seem to have different specificities in immunological reaction. Furthermore, in isoelectric focusing pattern of IgG, similar bands were identified in the extract of the cystic wall and fluid of same radicular cyst in 82% of the cases. These bands were detected in some of the dental sacs but not in the serum. Therefore it means that a quantities of IgG in periapical lesions and cystic fluids were locally produced. By quantitative analysis, no statistically significant differences were found in the concentration of IgG, IgG subclasses, IgA and IgM in sera between periapical lesion group and control group.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"27-47"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13767744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Changes of dentin matrices during carious process].","authors":"Y H Lin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Studies were made on the effects of demineralization with lactic acid or acetic acid on the organic matrices of human sound dentin, and on the changes of the matrices during carious process. When sound dentin was demineralized with 0.5 M lactic acid or 0.5M acetic acid, non-collagenous proteins and a small amount of collagen were extracted. A larger amount of protein containing phosphophoryn was extracted with lactic acid than with acetic acid, whereas when acetic acid was used for demineralization and then followed by an EDTA solution most of the phosphophoryn was removed. Since EDTA will remove phosphophoryn from sound dentin, low level of phosphophoryn in the extract obtained by treating carious dentin with EDTA, suggests that during the carious process a loss of phosphophoryn occurs. The analyses of carious dentin fractionated by the difference of its density showed that the lower density fraction of carious dentin contained a larger proportion of non-collagenous components to collagen. By the dansylation of sound and carious dentin nine dansyl amino acids, such as aspartic acid, glutamic acid, serine, glycine, alanine, proline, valine, leucine and tyrosine, were detected in the sound dentin, and in addition to these nine amino acids isoleucine was found in carious dentin. The amount of the respective dansyl amino acids in the fractionated carious dentin increased with the decrease of density.</p>","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"15 1","pages":"249-66"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13767742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[A clinical study on removing cemented post].","authors":"C Fukazawa,&nbsp;Y Nakamura,&nbsp;S Fukushima","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":76770,"journal":{"name":"Tsurumi shigaku. Tsurumi University dental journal","volume":"14 3","pages":"443-8"},"PeriodicalIF":0.0,"publicationDate":"1988-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14208979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}