Shigaku = Odontology; journal of Nihon Dental College最新文献

{"title":"[The muscle polarization of Drosophila larva].","authors":"T Fukuda","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>It has been clear that the polarization curve shows a peak phenomenon when the applying potential is increased. This peak was observed in the Drosophila larval muscle and it showed different between the normal and mutant. It was expected that the potential of polarization could be expressed as a simple exponential function when the applying potential was very weak. So it was tried in this article by using the Drosophila larva.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"274-82"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289663","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":"Inorganic elements in the tooth and bone tissues of rats bearing nickel acetate- and lead acetate-induced tumors.","authors":"Y Teraki,&nbsp;A Uchiumi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Biological effects of such metals as nickel and chromium alloys used as dental materials, particularly their metabolism and potential toxicity have not been well elucidated. Certain metallic materials are known to be toxic and arsenic, nickel, chromium and lead have been shown to have carcinogenic potential in laboratory animals. This study was performed to assess carcinogenicity and accumulation in tissues of metals in rats. Three-week old male F344/NSle rats were injected s. c. with 30 mg/kg of nickel acetate or 60 mg/kg of lead acetate weekly for 5 weeks after 2 weeks of acclimatization, and were followed by observation for 80 weeks. The group treated with lead acetate showed a greater incidence of tumor, compared with the nickel acetate-treated group. Teeth, femora, other bones and neoplastic tissue from tumor-bearing animals were subjected to elemental analysis by spectrophotometry and ICP. High concentrations of Pb were detected in the mandibula, femur and tumor tissue of rats with Pb-induced tumor. In rats with Ni-induced tumor, Ni was not demonstrable in the mandibula, maxilla or tumor tissue and detected in small quantities in the nasal bone and femur. Thus, Pb proved to be retained in tissue at the site of injection and also markedly accumulated in the tooth and femur as assessed 46 weeks after injections; whereas Ni was no longer detectable in tissue at the injection site, nor in tumor tissue but only small quantities in the said bones.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"269-73"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289664","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":"[SEM investigations on the human sclerosed dentinal tubules].","authors":"T Yagi,&nbsp;S Suga","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Sclerotic changes of dentinal tubules appeared in the dentin beneath the carious, attrition and abrasion lesions and in the transparent root dentin were investigated using the scanning electron microscopy. 1) Shape of crystal-like substances appeared in the dentinal tubules could not be closely related to kinds of dentin destruction. 2) In the dentinal tubules beneath the carious lesions, cuboidal or rhomboid-shaped, short rod-like, long rod-like, plate-like and droplet-like crystals were mainly observed. Combination of cuboidal or rhomboid-shaped and short rod-like crystals or that of long rod-like and plate-like crystals were most frequently observed. 3) In the dentinal tubules beneath attrition and abrasion lesions, cuboidal or rhomboid-shaped, short rod-like and droplet-like crystals were mainly observed, however, the size of cuboidal or rhomboid-shaped crystal was usually smaller than that observed beneath carious lesion and they deposited compactly within the tubules. 4) In the sclerosed dentinal tubules in the transparent root dentin, compact deposition of rhomboid-shaped and irregular sand-like crystals were usually observed. Size of rhomboid-shaped crystal is smaller than that observed beneath carious lesion. The deposit of sand-like crystal in the tubules was easily discriminated from the matrix of peritubular dentin. 5) In any case, the kinds of crystals and pattern of deposition were not necessarily same between the neighboring tubules. However, in a tubule, they were almost same in shape and mode of deposition throughout the entire length of tubule from the outer side to the pulpal side. These facts seem to indicate that mineral deposition within the tubule due to sclerosis is performed under individual condition. 6) Finding showing biological control of mineral deposition within the dentinal tubules by the odontoblasts could not be observed.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"313-37"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289666","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":"[Microradiographic investigations of carious changes in the enamel in the ground sections made perpendicularly to tooth axis].","authors":"T Mizuhashi,&nbsp;S Suga","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Carious changes in the enamel in the undermineralized ground sections made perpendicularly to tooth axis were investigated using microradiography. By this way, relationship between carious invasion and the enamel lamellae and tuft, which has been not able to be examined in the longitudinal ground sections, could be clarified. 1) Direction of progress of demineralization and contour of demineralization front in the enamel are closely related to arrangement of enamel prisms. This findings strongly suggest that carious demineralization progresses along the enamel prisms. 2) Mode of carious demineralization in the enamel lamellae can be divided into two types; in the first type, demineralization progresses through the enamel lamellae more quickly than in the surrounding enamel and, in the second type, the enamel lamellae and its surrounding enamel show higher mineralization degree than the demineralized part in the rest of enamel, probably due to remineralization. The second type is observed more frequently than the first. 3) Mode of carious demineralization in the enamel tuft are also divided into two types; the first type which shows that demineralization progresses more quickly through the enamel tuft than the surrounding enamel and the second type that the enamel tuft and its surrounding narrow enamel are highly mineralized probably due to remineralization, whereas the rest of enamel is prominently demineralized. The second type is more frequently observed than the first. 4) In the ground sections made perpendicularly to tooth axis, it is more clearly observed that the interprismatic area is very highly remineralized whereas the main body of prism is easily demineralized, than in the longitudinal ground sections. 5) Striae of Retzius is composed of the band which appear to resist to demineralization and that which is easily demineralized. However, in the later case, demineralization which progresses laterally along the band can not be observed. 6) The degree and width of hypermineralized layer appeared in sound enamel along the demineralization front seem to be related to the rate of demineralization and arrangement of enamel prisms.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"283-312"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289665","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":"[Past, now and future in endodontics].","authors":"Y Nakamura","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"191-207"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289766","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":"[Chemical composition and biological activities of lipopolysaccharides extracted from Treponema denticola and Treponema vincentii].","authors":"T Kurimoto,&nbsp;M Suzuki,&nbsp;T Watanabe","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Lipopolysaccharides (LPSs) were isolated from Treponema denticola (T. denticola) and Treponema vincentii (T. vincentii) by the phenol/water (PW) and the phenol/chloroform/petroleum-ether (PCP) procedures. 1) T. denticola PW-LPS (LPS isolated by the PW procedure), PCP-sup-LPS (LPS isolated by the PCP procedure in the supernates of ultracentrifugation), PCP-ppt-LPS (precipitated LPS isolated by the PCP procedure, obtained after ultracentrifugation), and T. vincentii PCP-ppt-LPS were composed of carbohydrate, hexosamine, protein, fatty acid, and phosphorus. T. vincentii PW-LPS was contained major amount of carbohydrates and small amount of fatty acids. 2-keto-3-deoxyoctonic acid (KDD) was not detected in these LPSs. 2) The major fatty acids of T. denticola PW-LPS and PCP-sup-LPS were palmitic, stearic, oleic, and linoleic acids. The major fatty acids of T. vincentii PCP-ppt-LPS were palmitic, stearic, myristic, oleic, and linoleic acids. Hydroxy fatty acids were not detected. 3) Glucose, galactose, and mannose were comprised in T. denticola PW-LPS. Glucose, galactose, and arabinose were comprised in T. denticola PCP-sup-LPS. Glucose and galactose were comprised in T. vincentii PCP-ppt-LPS. 4) The Limulus amoebocyte lysate (LAL) clotting activity of T. denticola PW-LPS was 1/10, as compared with that of Escherichia coli (E. coli) UKT-B LPS standard. The LAL clotting activities of T. denticola PCP-sup-LPS, T. vincentii PW-LPS, and T. vincentii PCP-ppt-LPS were 1/100, as compared with that of E. coli LPS standard. 5) Five hundred micrograms/kg of T. denticola PCP-sup-LPS was pyrogenic in rabbits. Two thousand micrograms/kg of T. vincentii PCP-ppt-LPS was pyrogenic in rabbits. 6) T. denticola PCP-sup-LPS and T. vincentii PCP-ppt-LPS were capable of increasing or decreasing the release of lysosomal enzymes from human polymorphonuclear leukocytes.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"208-32"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289660","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":"Studies on the distribution of mineral elements in the tooth of zinc-deficient rats.","authors":"Y Teraki,&nbsp;M Ishiyama","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Elemental analysis of plaque-like black deposits noted on the surface of teeth in zinc-deficient rats at necropsy was performed. Rats deficient in zinc show signs of abnormality in iron metabolism and increase or accumulation of iron in plasma and tissues. This study was designed, therefore, to examine the plasma and salivary levels of iron and other elements and to determine the distribution of mineral elements in the dental substances of zinc-deficient rats by contact microradiography, electron probe microanalysis (EPMA) and X-ray fluorescent element mapping spectrometry (XEMS) on ground sections of teeth. Rat tooth specimens were analyzed also for zinc, iron, copper and manganese using colorimetry and Inductively Coupled Plasma, ICP. EPMA and XEMS analyses revealed the presence of iron on the enamel surface of maxillary molars teeth of zinc-deficient rats. However, no such deposition was seen on those of controls. The zinc-deficient rats showed higher iron concentration in mixed saliva and in plasma, compared with the controls. Thus, the sign of abnormality in iron metabolism noted in the oral cavity of zinc-deficient rats was investigated by EPMA and XEMS analyses, with discussion on the origin of supradental iron deposits.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"251-7"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289661","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":"Tooth and bone tissue analysis by element mapping spectrometry.","authors":"Y Teraki,&nbsp;A Uchiumi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Elemental analyses of the tooth and bone tissues were carried out by X-ray fluorescence element mapping spectrometry, a technique we have recently developed. This analytical system has the advantage of providing data on distribution of element concentration in a given specimen in overhead view without involving destruction of the tissue architecture. This paper briefly introduces the apparatus of this system and presents analytical data obtained for several elements (calcium, iron, arsenic, zinc and strontium) in the tooth and bone tissues of rats bearing tumor induced with lead acetate. Lead distributed in the maxillary incisive bone and femur was demonstrated in rats with lead acetate-induced tumor sacrificed at 42 weeks after injections. Arsenic observed in the femur of control rats was found replaced by lead in the tumor bearing rats. The findings are of interest as viewed with reference to chelating activity of lead.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 2","pages":"259-68"},"PeriodicalIF":0.0,"publicationDate":"1990-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289662","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 study of developmental changes of Indian mandibles concerning development of weight, height, thickness and length of the mandible].","authors":"Y Furuta,&nbsp;O Nakaya,&nbsp;M Kuramochi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A total of 230 mandibles were classified into 7 groups 8 stages according to eruption phase, observing developmental changes from unerupted stage (Group A) to permanent dentition (Group G) 1. Development from Group A to deciduous dentition completion stage (Group C) was classified into 3 types. 1) Regarding height of mandibular ramus, height and weight of mandibular body, the increase from Group B where the deciduous central incisor erupts to Group C is greater that from Group A-B (type a). 2) As to coronoid process height, length of mandibular body, mandibular length and mandibular ramus width, equal increases were seen between Group A-B and B-C (type b). 3) Chin height and thickness of the mandibular body developed suddenly with the eruption of the deciduous central incisors. The increase is greater in Group A-B (type c). 2. They are classified according to size proportion in unerupted stage as compared to entire size. The classification are: 42%-33% (smaller), 50%-45% (medium), 70%-50% (bigger). 1) Type a is small at Group A and developed steadily after Group C. Development is greater, about 2.3-3 times. 3) Type b at Group A is larger than type a. It continuously developed after Group C. The developmental rate is about 2 times except the coronoid process height. 3) Type c is large at Group A. No development occurred after D1 stage when first molars erupt. Developmental rate is 1.4-1.85 times and smallest of the 3 types. 3. Developmental quantity: 1) Regarding total increase; The height of the mandibular ramus, the height of the mandibular ramus and coronoid process showed about 28-32 mm increase Group C accounted for 55%, Group C-D2 14%-17%, Group D2-G 30%-27% of the developmental increase. The mandibular ramus width showed increases of 14.43mm (74% at D1 stage) and subsequent increase was 7% between each group, showing equal increases. 2) Chin and mandibular ramus height showed increases of 14 mm. At Group C, development in chin height accounted for 67%. The mandibular body width increased 4.0mm-6.0mm at the foramen in m2/m2 and 6/6 portions. It reached 82%-100% in D1 stage. 3) An increase in mandibular body length and mandibular length was 50mm and 32mm, reaching 73% of the entire developmental amount by D1 stage.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 1","pages":"129-49"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289758","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":"[Clinical evaluation of protocol for the craniomandibular disorders. 3. Questionnaire for the craniomandibular disorders].","authors":"T Okamura,&nbsp;R Kawata,&nbsp;A Ohta,&nbsp;K Koide,&nbsp;S Hatate","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study is to clarify the effectiveness of questionnaire which is included in the protocol designed for screening the patients with extensive pathological states of craniomandibular disorders. 100 patients, with their ages ranging from 11 to 77 years old, were selected for the study and they were classified under various disorder classification which is based on the criteria of Japanese society for Temporomandibular Joint. Statistical analysis was performed to find the relationship between the different pathological states and the results of the questionnaire. The following results were obtained: 1. The ratio of appearance on TMJ pain was as follows: Type I (100%), Type II (0%), Type III (43.8-75.0%) and Type IV (75.0%). 2. The ratio of appearance on TMJ pain on chewing was as follows: Type I (50.0%), Type II (100%), Type III (20.0-100%) and type IV (37.5%). 3. The ratio of appearance on TMJ pain on maximum opening was as follows: Type I (100%), Type II (100%), Type III (50.0-100%) and Type IV (75.0%). 4. The ratio of appearance on TMJ noise was as follows: Type I (0%), Type II (0%), Type III (40.9-81.3%) and Type IV (50.0%). 5. The ratio of appearance on the fatigue by mastication was as follows: Type I (0%), Type II (50.0%), Type III (40.0-100%) and Type IV (75.0%). 6. The ratio of appearance on bruxism was as follows: Type I (0%), Type II (0%), Type III (10.4-40.0%) and Type IV (25.0%). 7. The ratio of appearance on the stiff of jaw on awakening was as follows: Type I (50.0%), Type II (0%), Type III (20.8-70.0%) and Type IV (37.5%). 8. The ratio of appearance on the unilateral chewing was as follows: Type I (50.0%), Type II (0%), Type III (20.0-50.0%) and Type IV (62.5%). 9. There were significances among those types about each items on the questionnaire, it can be suggested that the questionnaire for screening about craniomandibular disorders was effective.</p>","PeriodicalId":76539,"journal":{"name":"Shigaku = Odontology; journal of Nihon Dental College","volume":"78 1","pages":"115-28"},"PeriodicalIF":0.0,"publicationDate":"1990-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13289845","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}