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

The low molecular weight inhibitor (LMWI) and the translocation of dihydrotestosterone (DHT)-androgen binding protein (ABP) complex of the cytosol to the nuclei in rat submandibular gland (SMG) was studied by dialysis, ultrafiltration and glycerol linear gradient centrifugation procedures. Prebound cytosol was obtained by the incubation with 3H-DHT at 4 degrees C for 3hr in the presence or absence of 100 fold excess of unlabeled DHT prior to contact to nuclei. When prebound cytosol was dialyzed or ultrafiltrated, the binding ability of 3H-DHT-ABP complex to nuclei was increased up to 3 times of the control (nontreated prebound cytosol). The sedimentation rate of 3H-DHT-ABP complex by glycerol linear gradient centrifugation was 4S for dialyzed or ultrafiltrated prebound cytosol and 8S for control. These transformation of 8S to 4S and activation to the nuclear binding of 3H-DHT-ABP complex by dialysis or ultrafiltration were inhibited by molybdate in the prebound medium. The similar transformation of 8S to 4S and activation to the nuclear binding of 3H-DHT-ABP complex was shown in heated prebound cytosol. These results indicate that the LMWI regulate activation of 3H-DHT-ABP complex. The molecular weight of the dialyzed LMWI were estimated as 7,000 by dialysis or ultrafiltration membrane and SDS-PAGE. From the in vitro two step binding assay, it was revealed that rat SMG contained the low molecular weight protein (M. W. 7,000) in cytosol having a inhibitory effect on the translocation to the nuclei of 3H-DHT-ABP complex.

During the application of orthodontic force to a tooth, the surrounding tissues undergo changes of bone resorption and apposition, thereby resulting in tooth movement. The purpose of this study was to investigate the interrelationship between alveolar bone changes and the periodontal vascular network caused by extrusive orthodontic force using a scanning electron microscopy. Extrusive orthodontic force was applied to the mandibular 2nd and 3rd premolars of adult dogs. At the completion of the loading process, the inferior alveolar arteries were injected with a low viscosity MMA resin (Mercox). The following results were obtained. 1) At 3 days post-extrusion, various types of vascular network showing a loop pattern were seen along the direction of the tooth movement. 2) At 7 days post-extrusion, various types of vascular network with a hairpin loop pattern along the direction of the tooth movement were observed. Histologically, the fibers of periodontal ligament were stretched in the direction of the extrusion, Vascular hairpin loop formations were observed within the fibers of periodontal ligament. Bone apposition was not observed on the surface of alveolar bone. 3) At 14 days post-extrusion, a much more extensive and developed hairpin loop pattern occurred. Furthermore, new bone apposition was seen on the alveolar bone beneath under the hairpin loops. The periodontal ligament space was retained in the same width, even after bony apposition. 4) At 21 days post-extrusion, the tooth side microvascular network showed abundant low hairpin loops which anastomosed each other, and new spinous bony apposition was observed right below the periodontal vascular network. 5) At 30 days post-extrusion, the periodontal vascular network showed a almost normal appearance, with the rearrangement of vascular network. The surface of the spinous bony apposition became flat. The appositional bone had a lower degree of calcification than the alveolar bone in control group. 6) At 60 days post-extrusion, the periodontal vascular network completed the rearrangement of vasculature.

Radiographic changes in the temporomandibular joint (TMJ) generally mean structural bone changes. However, the TMJ has a complex structure and comparisons of histological and radiographic findings are seldom seen in the literature. The author examined 14 human cadavers, 21 TMJs, with lateral tomography and studied the areas of the radiographs histologically. The results were as follows. 1. Radiographic erosion observed in the depression for the lateral pterygoid muscle and in the posterior part of the condyle generally showed no histological changes. Only two erosions, one in the superior part of the condyle and the other in the anterior slope of the articular fossa, showed histological changes. 2. Radiographic sclerosis observed in the articular eminence and the posterior slope of the fossa revealed no histological changes. Four cases of sclerosis in the superior part of the condyle showed remodelling of the bone. 3. Radiographic osteophyte observed in the antero-superior part of the condyle, revealed remodelling and morphological changes corresponding to the radiographic findings. 4. Radiographic flattening observed in the articular eminence revealed histological remodelling changes that corresponded to the radiographic findings. 5. Radiographic concavity observed in the posterior part of the condyle showed no histological changes in this area. However, remodelling of the bone was observed in the superior part of the condyle. In conclusion, radiographic flattening and osteophyte indicated structural bone changes directly. However radiographic erosion and sclerosis must be interpreted with caution, because many cases showed no histological changes and the localization of these radiographic findings was important. Radiographic concavity also must be interpreted with caution, because most cases revealed no depression histologically, but showed proliferation of the bone in front of this region. It was also suggested that the technical terms that express radiographic findings must be questioned and discussed still more.

The purpose of this communication is to explain regarding with relationship between the development of skeletal Class III malocclusion and the tooth-to-denture base discrepancy especially those in the posterior part of dentition (posterior discrepancy). Four cases which had skeletal Class III malocclusion and had experienced unsuccessful orthodontic correction were presented to evaluate the causative factors of skeletal Class III malocclusion. The observation of serial cephalograms led us to the conclusion that the continuous forward displacement of the mandible was associated with superversion of maxillary and/or mandibular molars caused by the "squeezing out" effect of poterior discrepancy. Moreover, superversion of molar provides a less steep maxillary occlusal plane in the denture frame. Accordingly, a vertical expression of the posterior discrepancy may provide one of the best explanation for development of skeletal Class III malocclusion.

Proteoglycan, one of the major non-collagenous protein in the connective tissue, is bound with fibronectin and other cell adhesion proteins, and has a role in the formation of the tissue and the organ. Although the glycosaminoglycan components in various tissue have been widely investigated, the molecular structure of periodontal ligament proteoglycan (PDL-PG) was rarely reported. In present study, proteoglycans of bovine periodontal ligament were purified by chromatography from material adsorbed by DEAE-Sephacel from a guanidium HCl extract. The sequential chromatographic steps consisted of ion-exchange chromatography on DEAE-Sephacel in 4M urea and gel filtration on Sepharose CL-4B in 4M guanidium HCl. The preparation contained a relatively small proteoglycan (Mr = 132,000 dalton) and a free glycosaminoglycan chain (Mr = 88,000 dalton). A Mr = 58,000 dalton core protein was shown by gradient SDS gel electrophoresis after chondroitinase ABC or chondroitinase AC II treatment. The glycosaminoglycan chains after chondroitinase AC II hydrolysis were seen on gel as polydispersed, broad alcian blue staining material (Mr = 20,000-60,000 dalton) while chains were totally hydrolyzed by chondroitinase ABC. These indicate a chondroitin sulfate/dermatan sulate (CS/DS) hybrid glycosaminoglycan chain. Papain digestion of the proteoglycan resulted in a single glycosaminoglycan chain after SDS gel electrophoresis with no protein band. These results suggest that the PDL-PG is slightly larger than that of bone and contains a single chondroitin sulphate/dermatan sulphate chain attached to a 58 K core protein. Antisera raised against PDL-PGs cross-reacted with PDL-PGs but not with other PDL proteins or bone PGs. It has been shown that during biosynthesis of dematan sulfate, L-iduronic acid is formed by epimerization of D-glucuronic acid, and sulfation. The degree of epimerization and sulfation may be related to the function of PDL in buffering the mechanical force applied to the tooth.

It has been strongly suggested that the periapical lesion develop as a result of immunopathological response to continuous antigenic stimulation. Bacteria from root canal systems might be most important pathogenesis capable of inducing immunological reactions in periapical tissue. The purpose of this study, therefore, was clarify the immunological potentials of Bacteroides buccae (B. buccae) which was frequently isolated from root canals with chronic periapical lesion. Biological activities of B. buccae cellular components, such as lipopolysaccharides (LPS) and cellular protein were investigated on the enhancement of monocytes migration induction of interleukin 1 (IL-1) production, mitogenicity and polyclonal B cell activation. The localization of immunocompetent cells and B. buccae in human chronic periapical lesions were examined by biotin-avidin-horseradish peroxidase method, and peroxidase antiperoxidase methods using monoclonal antibodies. Following results were obtained. 1. On the lymulus lysafe clotting activity and Shwarzman activity of B. buccae LPS were about half of Salmonella typhimurium (S. typhimurium). 2. Both LPS and 38K protein preparations from B. buccae enhanced the activity of human peripheral monocytes migration and induced IL-1 production. 3. It was found that mitogenicity of LPS from B. buccae on splenocytes of BALB/c and BALB/c nu/nu mice was weaker than that of 38K protein, however mitogenicity on thymocytes were not shown in both preparations. 4. The polyclonal B cell activation on splenocytes of BALB/c nu/nu mice by B. buccae were remarkably induced by 38K protein, but LPS showed less activity elicit than 38K protein. 5. It might be suggested that the both LPS and 38K protein of B. buccae may depend on the activities of macrophage and lymphocytes. 6. Antigenic substance of B. buccae were found most commonly engulfed materials within macrophage and intercellular space in connective tissue. 7. Dense accumulation of T and B lymphocytes were observed gathering around the phagocytic macrophage (foam cell), the number of B lymphocytes around the macrophage was greater than that of T lymphocytes. 8. These findings indicated that both LPS and 38K protein from B. buccae have a wide regulation function of immunobiologic responses. Therefore, it was suggested that both LPS and 38K protein from B. buccae may play significant roles in the pathogenesis of periapical lesion.

The effect of the phosphorylated protein, phosvitin, on the formation of the calcium phosphate crystal was examined in metastable calcium phosphate solution. Addition of glass ceramics caused consumption of hydrochloric acid, as a result of the dissolution of metal oxides. The activities of dissolution and nucleation were both high in the case of CPS-SiC. Phosvitin affected only the nucleation process, not the dissolution process. The decrease of phosvitin concentration after the addition of materials demonstrated adsorption of phosvitin by the material surface. The thermodynamic stability of solution after several days maintained equilibrium against tricalcium phosphate (TCP) and especially against octacalcium phosphate (OCP). From these results, it is concluded that glass ceramic implants have potential to stimulate hydroxyapatite formation, even in the presence of matrix substances.

It has been proposed that bacteria in infected root canals are most important agents to pathogenesis of the periapical lesion. The aim of the present study was to examine the roles of macrophage on the mechanism of development of periapical lesion. Therefore the influences of bacteria isolated from infected root canals to macrophage functions and the effects of products from macrophage stimulated with bacterial components to periodontal tissue were investigated. In this study, sonic extracts prepared from Bacteroides buccae predominantly isolated from root canals were tested for its capacity of induction of chemotaxis and production of prostaglandin E2 and collagenase from human peripheral monocyte. Furthermore prostaglandin E2, collagenase production and alkaline phosphatase activity of fibroblasts from human periodontal ligament (HPLF), pulp (HPF) and gingiva (Gin 1) stimulated with macrophage conditioned medium (MCM) stimulated with B. buccae sonic extracts were examined. The results obtained were as follows. The sonic extract of B. buccae showed capacity to induce macrophage chemotaxis directly and by activation of serum complement, and the serum activated with sonic extract of B. buccae was more active than the serum activated with LPS of Salmonella typhimurium. Prostaglandin E2 production of macrophage was increased when the cells were stimulated by sonic extracts of B. buccae, but collagenase activity. toas not increased. MCM stimulated with sonic extracts of B. buccae fot 48 hours strongly induced PGE2 and collagenase production from HPLF and HPF, at the same time sonic extract showed the similar capacity of induction of the PGE2 production of MCM. But, HPF stimulated with sonic extract showed the low activity of induction of the PGE2 production. On the other hand, Gin 1 cell produced a few amount of the PGE2 when it was stimulated with MCM, but not produced collagenase. Alkaline phosphatase activity of HPLF and HPF had been inhibited by addition of MCM stimulated with B. buccae sonic extract.

As dental technologies become highly developed, techniques have been more diversified. From as aspect of prosthodontic practice, both esthetic and functional requirements are emphasized for coronal restoration and consequently, these should be considered in the routine procedure. In fabrication of coronal restorations, metal, porcelain and resin are commonly used, and there exists the various disadvantages for metal cast method due to complicated processes by using different dental materials. Therefore, an electroforming apparatus was developed by us to replace the conventional procedure by a cathode rotary system. It was applied for coronal restorations to allow an electroforming directly on a working model. An experiment was successfully conducted to apply for a veneer crown on abutment tooth of upper central incisor on plaster model. The results were obtained as follows, 1. It was become possible to construct a metal framework by the electroforming. 2. Metal framework can be constructed on the same working model without a duplication of it. 3. The combined system for cathode rotation and liquid circulation could shorten the electroposition time, and allows a high current density extending to 50 A/dm2.