Kanagawa shigaku. The Journal of the Kanagawa Odontological Society最新文献

The local immune mechanisms of which the IgA system is central are characterized by activity that is independent of the immune response of the body as a whole. Among these mechanisms, SIgA (secretory IgA) plays an important role. In measuring saliva/serum SIgA, the author used an EIA SIgA column set for saliva and for serum. Investigation of saliva SIgA concerned the correlation with saliva flow speed while investigation of serum SIgA concerned patients with oral dysfunctions and those inoculated with the HB preventive vaccine. A slightly negative correlation was observed between the saliva flow speed and the saliva SIgA value. Regarding serum SIgA, effect from the liver function was considered to be a factor among patients with oral dysfunctions. The antibody positive subjects among those inoculated with the HB vaccine are considered to reflect the response level of the antibody factor as well as individual differences in sensitivity and immune response. Among antibody negative subjects, however, there was a general tendency toward high values.

The process of denture fabrication entails a series of steps that begin with impression-taking. Dimensional accuracy and displacement of surface repeatability affect results in these individual steps. Although changes in individual materials have already been measured in the past, there has been almost no measurement up to now of denture fabrication up to the denture base, using the mucous membrane as the standard and then measuring changes in the displacement of surface repeatability for each step. Noticing this lack, the authors used a Scanning Electron Microscope (SEM), presently the only non-contact measuring instrument that can be used, and measured changes at the different stages including the mucous membrane, the impression materials, the plaster and the resin. A drying process is required for the mucous membrane, and such a process can cause changes in the mucous membrane which is the basis of measurement. For this reason, the authors used Araldite, a product from Ciba-Geigy AG, as a replica material and made replicas for all the test materials, using the replicas for measurement. Results were as follows: 1. Araldite was used as the replica material, thus making it possible with the SEM to observe changes in the displacement of surface repeatability at the individual stages. 2. Major changes in the accuracy of surface were observed during impression-taking and in the period of moving from the impression material to the plaster. 3. During high-power observation with the SEM, the fine bumps on the surface of the plaster and resin disappeared and the surfaces became smooth. This is believed to be the result of the separating agent and heat.

Of the researches on periodontal diseases, the changes occurred in the vasculature of peridontal membrane and the surrounding alveolar bone there-to-fore attracts much attention. In order to induce an experimental occlusal trauma, composite resin was added on the occlusal surfaces of mandibular second and third premolars of dogs to raise the bite for a period of time, followed by injection of methacrylate resin (MERCOX) into inferior alveolar artery and dissolution of soft tissues by protainase and examined under the scanning electron microscope (SEM, JEOL 35 C). The results are as follows: After 14 days, a wide range of avascularized area was observed on resin cast of periodontal membrane. The surface of alveolar bone on which the vasculature disappeared did not show resorption process. However, the surface of alveolar bone next to the periodontal vasculature showed undergoing a direct bone resorption. After 30 days, the vasculature of periodontal membrane underwent a morphological change and turned out to appear as a mesh-like vascular network. Certain avascularized regions was observed over the alveolar bone on margin region and cervical region, and it was circumscribed by a vasculature with glomerule-like loops. This vasculature was suspected originating from underlying alveolar bone marrow and connected with the residual vasculature of periodontal membrane. After 60 days, vasculature of periodontal membrane facing teeth appeared quite resemblance with that of health periodontal membrane. Those next to the alveolar bone, however, showed enlargement. In this period, avascularized area was not observed. After 90 days, the vasculature in periodontal membrane lost its original two-layered arrangement and replaced by the irregular arrayed bundle-like vasculature. Longitudinally arrayed mesh like vasculature was observed in certain region of periodontal vasculature. After 180 days, bundle-like vessels arrayed as an ellipse pattern. Also, resorption process could be observed on the surface of alveolar bone and interradicular septum. Experimental study of occlusal trauma on dentition clearly indicated that teeth were showed a mobility in vertical direction and that the vasculature of periodontal membrane were showed depression and elongation for a period of time. It could not show an apposition where were showed by the experimental depression and elongation, so it was only showed the expansible periodontal membrane space by resorption of alveolar bone.

The present study was carried out by fabrication of microcorrosive resin cast to investigate the vascular changes of periodontium of dogs' mandibular incisors with severe mobility and deep pocket formation concomitant with suppuration and alveolar bone loss. With aid of the dissolution of soft tissues by protease, alveolar bone remained left with resin cast of specimen, which then was referred for scanning electron microscopic examination. Results were as follows: 1. The vasculature of inner gingival epithelium which originally appeared as a flat, mesh-like network underwent a conformational change and turned out to be a vasculature with glomerulus-like loops due to chronic inflammation. 2. No remarkable change was ever identified in vasculature of periodontal ligament surrounding cervix of tooth. 3. Certain parts of vasculature of periodontal ligament disappeared, which combining with the occlusion indicated the occurrence of occlusal trauma. 4. Exposed alveolar bone surface where the periodontal vasculature disappeared showed an amorphous, flat surface. Quite contrast to this, the surface of alveolar bone on which the vasculature is located appeared undergoing a resorptive process. 5. Accordingly, the damage occurred in periodontium was not merely due to chronic inflammation but to the accompanying occlusal trauma which was supposed to be a predominant factor.

Masicatory function is the result of a highly complicated neuromuscular activity which coordinates in stomatognathie system. Functional directions of masticatory cycles in areas of intercuspal position (IP) were objectively evaluated on each stroke obtained through the Sirognathography Analyzing System (S. G. G./A. S.; Siemens, W. Germany). Twenty seven dantate subjects were selected at random from students and staff members of Kanagawa Dental College. A piece of chewing gum was given to each subject to masticate it for a minute on one side and on the other side respectively. A total of masticatory cycles were successively recorded into S. G. G./A. S.. A statistical analysis, the equal probability for ellipstical variations, was made on the angular measurements from opening and closing phases of each cycle within 3 mm from onset and terminus in areas of IP during masticatory movements. Four characteristic features of angular measurements are presented, namely, subjects who showed different types in position and forms by plotted angles within 80% of total amounts. The following results were obtained from this study. 1. Functional directions of masticatory cycles are clearly recognized in areas of IP from opening and closing phases during masticatory movements. 2. An application of the equal probability for ellipstical variations seems to be efficient for the functional analysis of masticatory cycles. 3. A classification of different types of plotted angles contributes to become a basis for diagnosis of masticatory function and occlusion.

This study was made to improve the validity of age estimation from teeth using amino acid racemization. The correlation between actual age and the D/L ratio of aspartic acid was investigated by analyzing not only total amino acid but its fractionated substances, insoluble collagen and soluble peptide. The coefficient values of correlation between the D/L ratio and actual age in lower central incisors were 0.996 (sigma = 1.0 years) for total amino acid, 0.998 (sigma = +/- 1.8 years) for insoluble collagen, and 0.997 (sigma = +/- 0.9 years) for soluble peptide. The corresponding figures in upper and lower first premolars were 0.991 (sigma = +/- 1.6 years), 0.989 (sigma = +/- 1.9 years), and 0.994 (sigma = +/- 1.4 years), respectively. The reactive velocity of aspartic acid racemization was highest for soluble peptide both in lower central incisors and upper and lower first premolars, approximately three times as rapid as that for total amino acid. The velocity for insoluble collagen was slightly lower than that for total amino acid. Age estimation was attempted from the teeth of an unknown body. As a result, age estimated from the analysis of soluble peptide was most accurate. These results suggest that the analysis not only of total amino acid in dentin but its fractionated and extracted substances can lead to higher reliability in age estimation. Soluble peptide, in particular, has been found to be most effective.

The present study attempts to explore the newly synthesized phosphoproteins secreted by osteoblast-like cells incubated with 1,25(OH)2D3. The phosphoproteins, which are non-collagenous proteins, may possess the ability to regulate bone mineral solubility. An osteoblast-enriched cell population isolated from 2 day-old rat calvaria by sequential enzymatic digestion was cultured in a defined medium containing dialized fetal calf serum protein (FCSP, 2 mg/ml) with 1, 5 and 10 x 10(-9)M 1,25(OH)2D3. At confluence, 32Pi (Na2H32PO4, NEX-011) was added for 24 hr. The medium proteins were precipitated by cold 10% TCA, dissolved in 15 mM Tris-HCl, pH 7.4 containing 7 M urea and chromatographed on hydroxyapatite columns (Bio-Rad, HTP). After stepwise elution with 6 mM, 0.1, 0.5 and 1.5 M Pi Hepes buffer pH 7.4 containing 3 M urea and 5 mM levamisole, the phosphoproteins were applied to 10% SDS-PAGE and autoradiographed. The 32Pi incorporated phosphoproteins of 75K, 66K, 58K, 42K, 38K, 24K, 22K, 19K, 15.5K, 13K and 3.5-10K molecular weight which were bound on a hydroxyapatite column were identified on autoradiograms of SDS-PAGE. The synthesis of 19K phosphoprotein was stable. However the synthesis of 75K, 66K, 38K and 15.5K phosphoproteins were increased by 1,25(OH)2D3. Therefore, 1,25(OH)2D3 induced phosphoproteins synthesized in rat calvarial osteoblasts, which can bind tightly on hydroxyapatite, may regulate the solubility of bone mineral and play a role in maintaining a blood/bone equilibrium.

In our study of the interaction between dental implant materials and human serum proteins, a simple column chromatographic method to measure extraction of proteins by the biomaterials was developed. The method allows for subsequent analysis of the absorped proteins by two dimensional microelectrophoresis. A system to measure dyestained proteins on two-dimensional polyacrylamide gels employing a television camera for data acquisition and a micro computer for data analysis is described. It can be seen that elution from the hydroxyapatite columns are qualitatively similar, more protein eluting at 0.1 M phosphate. Less protein was adsorbed by the 1,250 degrees C and 1,400 degrees C hydroxyapatite ceramics, and equal amounts were eluted with 0.01 M and 0.1 M phosphate solutions. The 0.1 M phosphate eluates were subsequently analyzed by two-dimensional electrophoresis. The proteins adsorbed band eluted from the biomaterials, are estimated to be albumin, pl 4.7-4.9; transferin, pl 5.9 and IgG, pl 5.8-7.3. pl's were obtained from literature and tentative identifications made by comparison with the patterns of reference serum. The protein pattern from each biomaterial was reproducible. Albumin, IgG and transferin were obtained from non-treated hydroxyapatite. Different patterns were observed with eluates of 1,250 degrees C and 1,450 degrees C hydroxyapatite ceramics. The large spot, tentatively identified as albumin and a small amount of IgG, were the only proteins seen. We conclude that hydroxyapatite and hydroxyapatite ceramics can adsorbed of human serum protein. Selective adsorption of protein may occur a structure change of the material surface activated by sintered temperature.

Saito et al recently reported that the alkaline phosphatase (ALPase) of human periodontal ligament fibroblasts (HPLF) showed remarkably high activity which was similar, but not identical phenotype, to that present in osteoblasts, and suggested that HPLF could be termed as "osteoblastic fibroblast." The present study attempts to explore the ALPase synthesized on HPLF in relation to 1,25(OH)2D3. These HPLF were obtained by the explantation method and then subcultured in D-MEM containing 2 mg FCSP/ml, 50 micrograms ascorbic acid/ml and penicillin/streptomycin after trypsinization. The HPLF were inoculated at a cell density of 1.25 x 10(4) cells/cm2 in culture wells. After 24hr, the HPLF were treated every two days for 7 days with 0.5-10nM 1,25 (OH)2D3. Then, ALPase activity, DNA and protein contents were assayed by the methods using p-nitrophenylphosphate, diaminobenzoic acid and Coomassie Brilliant Blue, respectively. Also, ALPase was prepared from the confluent HPLF incubated with 5 nM 1,25 (OH)2D3 for 12 days, and digested with and without trypsin. The crude ALPase which was solubilized with 10mM Tris-HCl, pH 7.4 containing 0.2 mM MgCl2 and 0.1% NP-40 was applied to 5-15% gradient SDS-PAGE and stained with beta-naphththylacid phosphate and First Blue BB salt in 60 mM borate buffer pH 9.7. The cell growth which was assayed by DNA contents and the incorporation of 3H-thymidine was decreased by 1,25(OH)2D3. On the other hand, ALPase activity was increased approximately 3.6 fold at 6 day by the addition of 5 nM 1,25(OH)2D3. From the separation of ALPase activity on SDS-PAGE, 110 K and 120-130 K ALPase were identified. The 110 K ALPase, which was not changed by 1,25(OH)2D3, was converted to 100K, releasing 10K peptide after trypsin treatment. This 110K ALPase might be tightly associated with cell membrane structure. The 120-130K ALPase was remarkably increased by 1,25(OH)2D3 on SDS-PAGE and completely digested with trypsin. The ALPase in the cultured HPLF might be located not only on the plasma membrane but also in the extracellular matrix. Therefore, 1,25(OH)2D3 may regulate the cell cycle and also the gene expression of ALPase of HPLF.

The ability of crude extracellular enzyme produced by the bacterium Streptococcus mutans AL-7 to lysis the cells of five species, sixteen strains, of oral streptococci was examined. This enzyme showed lytic activity of living cells of only Streptococcus sanguis ATCC 10558 strain, and of heated cells of Streptococcus sanguis ATCC 10558 and ST-7 strains. The long chains of Streptococcus sanguis ATCC 10558 was severed at random by this enzyme. Early log phase cells of this strain were more sensitive to this enzyme than late log phase cells. No bacteriocins or bacteriocin-like substances were produced by Streptococcus mutans AL-7 strain in chemically defined medium. In view of these results, the relationship between this lytic enzyme from Streptococcus mutans and a decrease in the number of serotype III strains of Streptococcus sanguis in dental plaque is suggested.