Nihon Shishubyo Gakkai kaishi最新文献

Samples of subgingival bacteria were collected from two sites of offanteriors with greater than or equal to 6 mm deep pockets in each ten patients in a clinically characterized rapidly progressive periodontal disease. The purpose of this investigation was to study the predominant cultivable microflora at pre- and post-periodontal treatment stages, in order to monitor the clinical effects of periodontal treatment and possibly to determine the presence or absence of active disease. "Non effective site" was defined as little elimination of periodontal pocket. Some patients responded remarkably well to root curettage. However the subgingival flora of effective sites, which had been successfully treated and maintained over a period of three weeks, was still significantly different from the subgingival floras of people with healthy gingiva. The predominant cultivable microflora of diseased lesions at the pre-treatment stage, in which a similar proportion of microbiota were detected on both sites in each patient, were significantly increased proportions of Bacteroides sp., B. intermedius and B. gingivalis. Although B. gingivalis has been implicated as the etiologic agent of the disease, to which marked antibody response has been found in periodontal pockets, there were decreased proportions of B. intermedius and B. gingivalis after treatment, compared to pre-treatment stage. The results showed that non-effective lesions were associated with subgingival microflora which were populated by higher proportions of B. intermedius and E. corrodens. H. actinomycetemcomitans were detectable during the experimental periods in all sites. It was possible to indicate progressing periodontitis by examining these microflora at the pre-treatment stage. However active or progressing disease in young adults might represent not only an overgrowth of existing organisms but also an abnormality in host resistance.

The purpose of this study was to investigate the effects of different methods of brushing on plaque removal, using O'Leary's plaque Control Record during initial preparation. The results were as follows: 1. There were many 40-50 year-old patients and they showed a 63.0 percent first visit Plaque Control Record average. 2. Many of the patients entering the clinic had periodontal disease in mild stages. 3. In most cases the toothbrushing methods were the Rolling method and the Modified Stillman's method. Of the patients, 73.5% achieved Plaque Control scores at the 20 percent level. 4. Of the patients who had achieved a Plaque Control Record at the 20 percent level, half of the patients instructed to brush using the Rolling method had developed moderate forms of periodontal diseases, and half of the patients instructed to use the Modified Stillman's method had developed mild forms of periodontal disease. There is a close relationship between toothbrushing methods and the progression of diseases, and this shows that Plaque removal methods should be controlled.

The purpose of this study was to analyze antigens of Actinobacillus actinomycetemcomitans. Fifteen hybridomas producing monoclonal antibodies (MAbs) against A. actinomycetemcomitans strain Y4 were obtained. These hybridomas were divided into three groups (Group 1, Group 2 and Group 3) on their MAbs' specificity. The MAbs (MAb S1-S8) produced by Group 1 hybridomas reacted with serotype b-specific antigen of A. actinomycetemcomitans. The MAbs (MAb L1-L3) produced by Group 2 hybridomas reacted with lipopolysaccharides (LPSs) of all serotypes of A. actinomycetemcomitans. The high-molecular-weight peak (peak A) and the low-molecular-weight peak (peak B) were separated by gel-filtration of the phenol-water extract (PWE) of strain Y4. MAb S5 reacted with peak A, and MAb L2 reacted with peak B. Peak B bound to a polymyxin affinity column, but peak A did not. These findings indicate that peak A was serotype-specific antigen and peak B was LPS. MAbs P1, P2, P3 and P4 produced by Group 3 hybridomas reacted with 81 kDa, 64 kDa, 64 kDa and 40 kDa protein antigens, respectively. Preincubation of strain Y4 whole cells with MAb P3 inhibited significantly the adherence of the cells to human buccal epithelium cells (HBECs). These findings suggest that the 64 kDa protein antigen might participate in the adherence of A. actinomycetemcomitans to HBECs.

The purpose of the present studies was to examine the healing process following the free gingival autograft placed on the recipient bed either with or without periosteum in 54 adult mongrel dogs with healthy periodontium. A recipient bed was prepared on denuded alveolar bone in a definite portion of the attached gingiva of the right maxillary canine tooth, and the graft was taken from the attached gingiva of the left maxillary canine and transplanted in the recipient bed. Morphological changes were observed by means of vascular corrosion casts on the postoperatively 3rd, 5th, 14th, 21st, 28th, 42nd, 56th and 84th day. The healing process following the free gingival autograft on the denuded alveolar bone showed that this graft survived in its margin by recirculation from the cut margin of the recipient bed, and in its center the necrotic tissue changed to granulation tissue, which gradually cicatrized. This was different from the healing process following the free gingival autograft on periosteum, in which the graft was survived entirely by recirculation from the vascular plexus of the periosteum on the recipient bed. This may help to restore the function proper.

The purpose of this study was to investigate the variations in oral hygiene conditions after oral hygiene instruction. We divided the patients with periodontitis into three groups according to the number of times oral hygiene instruction had to be given to achieve the O'Leary plaque control record (PCR) of 20%. The first group was those who achieved PCR 20% quickly (early achievement group). The second group was those who achieved PCR 20% gradually but slowly (slow achievement group). And the third group was those who showed no progress at all (non achievement group). Results showed that there were statistical differences among the average changes in PCR and residual plaque score (PS) of the teeth surfaces in each group. Especially the early achievement group were significantly superior to the other groups in improvement of PS of mandibular lingual surface with one oral hygiene instruction. We also have investigated differences in the probing depth, age and sex at initial treatment among these three groups. The average probing depth at initial treatment was significantly deeper in the non achievement group than in the early achievement groups, and there were more males than females in the early achievement and non achievement groups.

Two established osteogenic cell lines (NY, MC 3 T3-E 1) were used in vitro to determine the biocompatibility of glass ceramics and their effect on initial calcification of osteogenic cells. Morphological study of the cell under the phase-contrast microscopy and histochemical staining were applied as follows. First, glass ceramic granules were placed in 60 mm dishes, and cells were suspended in the dishes in alpha-MEM supplemented with 10% FBS (basic medium) or medium with 50 micrograms/ml of L-ascorbic acid added. After 8 or 14 day of culturing, calcium formation was tested by von-Kossa's staining. Also, alkaline phosphatase staining was performed by the azo-dye method. As controls, cultures in dishes without glass ceramic granules were stained at the same time. The results obtained in the experimental culture were as follows. 1. Phase contrast microscopy showed that contacts with glass ceramics did not cause cellular death or degeneration. 2. In both cell cultures with the glass ceramics the von-Kossa reaction was positive as early as the 8th day. 3. The alkaline phosphatase reaction on the 8th day occurred only in MC 3 T3-E 1. The reaction was localized on fibroblastic cells which proliferated three-dimensionally around glass ceramics, and on small polyhedral cells situated relatively for apart from the ceramics. 4. On the 14th day, the MC 3 T 3-E 1 formed large nodules around the glass ceramics, and they were stained uniformly positive by von-Kossa's method. The alkaline phosphatase-positive cells extended spoke-like forms. 5. In medium with L-ascorbic acid, growth of NY was inhibited, After being cultured for 14 days, abundant von-Kossa positive reaction was found around glass ceramics in both cells. In MC 3 T 3-E1 on the 8th days, the alkaline phosphatase reaction was stronger with glass ceramics than with basic medium only. On the contrary, in the control cultures of both cells there was negative von-Kossa reaction during the culture period. The above results showed that glass ceramic granules have the biocompatibility needed for bone grafts, and they facilitated calcification of MC 3 T 3-E 1 in culture.

The therapeutic effect of superoxide dismutase (SOD) and the role of O2- were assessed on 3 groups of Wistar rats (total 115). Fifty-four received injections of gingival bacteria or of anaerobically cultured rat dental plaque in their peritoneum, then received both intravenous (i.v.) and intraperitoneal (i.p.) injection of SOD. The rats were killed 48 hours later to collect their peritoneal exudate for cell count and for acid phosphatase activity assessment. Twenty-six received injections of bacteria in their footpads, after which SOD was administered intravenously. These rats were killed at 6 hours, 48 hours and 1 week respectively for histological examination. The gingiva of 26 rats were incised to create artificial lesions. The rats were killed at 24 or 48 hours and examined histologically. The nine remaining rats were used as controls (untreated) for the 3 experiments. The results of the 3 experiments showed that: Injection of SOD reduced exudation and acid phosphatase activity enhanced by the injection of B. gingivalis, at dosages of 1, 5 mg/kg i.p. and 5 mg/kg i.v., but 10 mg/kg i.p. had no apparent effect; i.v. injection of SOD had inhibitory effects on cell infiltration of B. gingivalis into the footpad, and the increase in fibrin and fibroblast formation through time was greater in SOD-administered rats; a decreased cell infiltration rate and increased fibrin network, fibroblast proliferation and gingival tissue regeneration occurred in specimens with artificial lesions given SOD. Apparently SOD has a curative effect on both inflammatory reaction induced by B. gingivalis and periodontal wound healing.

Seven juvenile periodontally diseased patients were evaluated for clinical, microbiologic and local or systemic host factors. Three patients showed the localized from of periodontitis clinically and radiographically and by deep periodontal pockets associated with the molars and incisors. Four were in the generalized froms, in which in most cases all teeth were affected. The results in both diseased froms on the predominant cultivable subgingival microflora, the composition of which was not different from that in adult periodontitis, consisted of significantly increased proportions of Gram-negative anaerobic rods, Bacteroides sp. and B. gingivalis, Haemophilus sp. and H. actinomycetemcomitans were detected in 1/3 of the localized and 2/4 of the generalized periodontitis. They were of no value in distinguishing activity that enhanced disease in the generalized from. Elevated serum IgG responses were noted with B. gingivalis. No markedly functional abnormalities of neutrophils from peripheral blood have been demonstrated, however it might function with systemic factors, like an insulin-dependent diabetes. Morphologic characteristics of the oral and periodontal tissue in localized periodontitis were that the pattern of destruction was confined to specific teeth groups characterized by extensive the bucco-lingual width ratio of the dental crown to alveolar bone width. These observations indicate that the generalized form of juvenile periodontitis lesions were associated not only with the presence of subgingival bacteria, but also with conditions such as local morphologic and systemic or constitutional factors, individual variation in relation to destructive and protective aspects of the defense mechanisms.

We examined PGE2 synthesis using inflamed and non-inflamed GCF PMNs and PB PMNs in the presence and absence of certain stimulators. The basal levels of PGE2 release from GCF PMNs isolated from ligature-induced gingival sulcus with a GI value over 2.2 were significantly lower than those from GCF PMNs isolated from sham operated sites with a GI value below 2.1. Levels were comparable to those from PB PMNs isolated at each experimental period, indicating that the amount of PGE2 synthesized by GCF PMNs is not correlated exactly with the severity of periodontitis. Calcium ionophore A23187 stimulated PGE2 synthesis by all PMN preparations. When compared to those with inflamed and non-inflamed GCF PMNs, stimulation was higher with PB PMNs. However, the chemotactic factor fMLP inhibited the synthesis by inflamed and non-inflamed GCF PMNs. PGE2 synthesis by PB PMNs isolated after periodontal operation was stimulated by the drug, but those cells isolated before the operation did not respond.