The biological effect of lipopolysaccharides LPS from Porphyromonas gingivalis (P. gingivalis) on murine periodontal tissue was assessed in comparison with the effect of LPS from Escherichia coli (E. coli). P. gingivalis LPS was injected into non-immunized or LPS-preimmunized mouse gingiva different numbers of times (1, 4, 7, 10, 13 or 20), and E. coli LPS was injected into non-immunized or LPS-preimmunized mouse gingiva in a similar manner. Before LPS was injected into the gingiva, serum levels of antibody against LPS were measured by enzyme-linked immunosorbent assay ELISA. Destruction of gingival tissue and osteoclastic bone resorption were assessed histopathologically. The results showed that the inflammatory changes in LPS-preimmunized mice gingiva were more severe than in non-immunized mice when E. coli LPS was injected 1 time. After 4 injections, gingival inflammation became more severe and osteoclastic bone resorption was increasingly observed equally in non-immunized and LPS -preimmunized mice . On the other hand, in the P. gingivalis LPS injection group, milder inflammatory changes and less alveolar bone resorption were observed, and there was little difference between the histological changes in the non-immunized mice and the LPS-preimmunized mice. These findings suggest that the in vivo biological activity of P. gingivalis LPS, which induces destruction of gingival tissue and osteoclastic bone resorption, is weaker than that of E. coli LPS.

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This study was designed to investigate the immunohistochemical localization of heparan sulfate (HS) using monoclonal antibody (HepSS-1) in the periodontal tissues of dogs during experimental periodontitis. Periodontitis was induced by floss ligature placement in the gingival crevices. The ligatures were left in place for periods of 3, 7 and 21 days.
In the healthy tissue, HS was located in the intra and intercellular spaces of the gingival epithelium. HS was also present in cells (blood vessel cells, nerve cells and fibroblasts) in the healthy gingival connective tissue and periodontal membrane.
The localization pattern of HS in inflamed tissue was similar to its localization in healthy tissue expect staining response in the intercellualr spaces of the gingival epithelium. HS was also found in the osteoclastic cells detected in the resorption lacunae of alveolar bone in the acute phase of inflammation.
These findings indicate that HS may play a role in cell metabolism in addition to tissue construction.

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To determine the localization of various inflammatory interleukins (ILs) in inflamed human gingival tissue, we performed an immunohistochemical study using antibodies against interleukin-1α (IL 1α), interleukin-1β (IL 1β) and interleukin-6 IL 6). We observed IL 1α-positive staining in junctional epithelium, oral sulcular or pocket epithelium and in neutrophils and macrophages infiltrating into the connective tissue just beneath these epithelia lining the inner margin of the gingiva. The positive staining pattern for IL 1β was almost the same as for IL 1α The staining intensity of each IL 1 differed in the epithelia and infiltrating cells in the connective tissue, that is, IL 1α staining was more intense in the epithelia than in the infiltrating cells, whereas IL 1β staining was more intense in the infiltrating cells. Immunoreactivity for IL 6 was detected in plasma cells and cells adjacent to them in addition to cells which were positive for all IL 1 staining. Since these three ILs were exclusively localized in the inner marginal portion of gingiva, where apparent histologic changes occur in periodontitis, they appear to play some role in the initiation and progression of inflammatory periodontal disease.

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In this study we ultrastructurally examined the attachment regenerated structures to root surfaces after initial root planing procedures.
The incisors of 3 beagle dogs were used. Periodontally involved tooth surfaces were ligated with cotton threads around the teeth in 24 weeks. For initial therapy, these lesioned root surfaces were planed with hand scalers. In the RP-A group the superficial zone of cementum was removed, whereas in the RP-B group the cementum was completely removed. The others root surfaces were not planed as control group. Specimens were processed and examined by transmission electron microscopy.
In the control group periodontal pockets were still present at 8 weeks. In both the RP-A and the RP -B group the cementum surfaces and denuded dentin surfaces were covered with long junctional epithelium. The epithelial attachment apparatuses in the RP-B group were better developed than in the RP-A group. In the RP-B group newly formed cementum matrices were observed on electron -dense granular layer which was present at denuded dentin surfaces.
Root planing procedures performed exhausively in the initial phase may produce regeneration of epithelial attachment and connective tissue attachment to periodontally involved root surfaces.

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Human periodontal ligament-derived fibroblasts HPLFs were grown to a preconfluent monolayer, trypsinized and used in a chemotaxis assay. HPLF -conditioned medium (HPLF-CM) was harvested from confluent monolayers and concentrated by ultrafiltration with a YM-5 diaflow membrane, fractioned in a P0-60 K column, and eluted with PBS (-) containing 0.1 mM phenylmethyl sulfonyl fluoride (PMSF), separating the medium into eight fractions (FI-VIII). Whole HPLF-CM has been shown to selectively enhance HPLF adhesion, spreading and proliferation. Boyden blind-well chambers equipped with double membranse were incubated with HPLFs in the upper compartment and with whole HPLF-CM, the eight fractions and plasma fibronectin as a positive chemoattractant control in the lower compartment. HPLFs in a dose-dependent manner, with maximal migration occurring at a concentration of 1.2μg/ml FN. We found that the whole HPLF-CM fractions, especially F-III, induced significant chemotactic activity. The molecular weight of F-III was estimated to be approximately 70 kDa.

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The aim of this study was to histopathologically clarify the role of B lymphocytes on the initiation time and the degree of destruction of periodontal tissue when endotoxin derived from Escherichia coli was injected into the gingiva of severe combined immunodeficient (SCID) mice. In comparison with our previous report on normal and nude mice using the same methods, the inflammatory changes in the gingiva of SCID mice were milder than in normal mice, and the appearance of osteoclasts in alveolar bone was delayed. These findings were almost the same as in nude mice, except for the proportion of inflammatory cells. These findings suggested that the milder inflammatory changes were due to an absence of functional T and B lymphocytes. On the other hand, the onset of alveolar bone resorption, which was also delayed in nude mice, appears to be more affected by T lymphocytes than B lymphocytes.

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In order to more clearly define the microvasculature of the periodontal ligament of the rat, an animal frequently used as an experimental model in studies on periodontal diseases and aging. We examined the histological structure and microvasculature of the periodontal ligament of the lower first molar in 3-month-old male Wistar rats whose roots had grown fully to secure complete occlusive function.
The periodontal vasculature formed a rough vasoganglion rete of thick arteriolovenules close to the alveolar bone in the apical part where the capillaries formed dense hairpin loops towards the coronal side of the root surface. This appeared as an arcade-like structure with the feet of the hairpin loops shortening as they approached the root center, becoming bundle-shaped as the loop disappeared at the alveolar crest.
Thus, examination of the periodontal vessels revealed morphological differences in the respective vasculature of the apical, central and crest regions of the tooth.

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The purpose of this study was to determine the antimicrobial effects of oridonin isolated from enmei-so (Rabdosia trichocarpa, Rabdosia japonica) on oral microorganisms in vitro. Fourteen strains of 13 species of oral microorganisms, including 1 strain of C. albicans, were cultured with oridonin in broth. Inhibition was assessed by measuring the turbidity of the broth in relation to optical density at 550nm (OD₅₅₀). The inhibitory concentration (IC) was defined as the concentration at which turbidity was equal to or less than 0.1.
Oridonin displayed an antimicrobial effect on the oral microorganisms tested, especially on Actinomyces, but only a weak effect on P. gingivalis and P. intermedia, and none at all on C. albicans. The finding that oridonin has a strong inhibitory effect on Actinomyces species suggested that oridonin may also have an inhibitory effect on the development of periodontitis, since Actinomyces are initial components of infragingival dental plaque and facilitate the migration of periodontal pathogens such as P. gingivalis and P. intermedia into gingival sulci or periodontal pockets.

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Interleukin 2 (IL-2) may play and important role in periodontitis, and previous studies have demonstrated that granzyme A (Gra-A) may be a mediator of cytotoxicity. The reverse transcriptase -polymerase chain reaction (RT-PCR) assay was used to determine whether cells from gingival tissue are capable of expressing Gra-A and IL-2.
IL-2 expression was detected in all gingival tissue samples from patients with periodontitis, but Gra-A expression was detected in any of the smaples. Gingival tissue infiltrates expressing Gra-A contained a great many CD 8-positive cells.
In this study we used a Gra-A probe on gingival tissue from periodontitis patients for the earliest possible detection of the acute stage.

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The purpose of this study was to determine the role of the periosteal vasoganglion in the periodontal region and closely observe vascular dynamics in the restorative process of the vasoganglion following free gingival autografts on denuded alveolar bone. We used 45 mongrel dogs with healthy periodontium in the experiment. Free gingiva was autografted on denuded alveolar bone in accordance with Yanagihara's method. The recipient bed was prepared in a definite position of the attached gingiva of the right maxillary canine tooth. The graft was taken from the attached gingiva on the left. Changes in the periosteal vasoganglion manifested in vascular casts were closely examined on postoperative days 3, 5, 7, 14, 21, 28, 42, 56, and 84. As a result, it was found that during the healing process following the free gingival autograft, the periosteal vessels progressed from the cut margin of the recipient bed in the marginal part of the graft, whereas new vessels grew out from the bone or marginal portion in the area between the margin and the center.

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The purpose of this study was to evaluate the effect of periodontal treatment based on the movement of human periodontal fibroblasts in vitro. Two modalities of root reatment were performed in experimental groups, 1) planed diseased root surfaces leaving cementum close to the cemento-dentin junction, intact or RP, 2) RP followed by citric acid, or RP+CA. Root slices were prepared from surgically extracted normal human and periodontally diseased teeth. Two control groups were established, 1) a normal root cementum or N group, and 2) diseased root cementum or P group. Each treated root slice was placed in a well of a 24-well plate and 1×10⁴ cells in1ml of α-MEM were added with subsequent incubation for 56 days.
Scanning electron microscopic examination during the initial incubation period, showed that the fibroblasts on the N-roots, the RP-roots and the RP+CA roots appeared spindle-shaped with a few processes. The cells on the P-roots were round or slightly elongated. Root planing removed 52% of the endotoxin in the diseased root cementum, and 64% were eliminated by root planing followe by citric acid application. No significant differences were found between the numbers of cells or the amount of DNA in the cells in RP-roots and RP+ CA roots in the early proliferation stage. The ALPase activity of the cells on the N roots and the RP-F CA roots was double its activity on the P roots and RP roots at the end of the experimental period.
The present findings suggest that root planing which left cementum close to the cemento-dentin junction intact enhanced initial cell proliferation on root surfaces because of the removal of endotoxins that had penetrated into a thin layer near the root surface. Citric acid application appeared to have an additional effect in promoting adherence and differentiation of fibroblasts.

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The purpose of this study was to clinically and microbiologically evaluate the effects of local drug delivery of Periocline® in combination with scaling and root planing (SR). This study was performed during supragingival mechanical plaque control. The four groups, i. e., I: treated only by SR, II: Periocline® applied after SR, III: Periocline® applied twice, after SR and after one week, IV: Periocline® applied four times, after SR and once a week three weeks, were assessed clinically (PD, AL, GI, BoP and SI) and microbiologically by phase contrast microscopy and anaerobic culture before and after treatment.
The results obtained were as follows:
1. Group IV showed greater improvement in PD, AL and GI than group I. The percentage of sites which bled when probed was increasingly lower in group I, II, III and IV. Sites discharging pus disappeared after treatment in all of the groups.
2. There were no significant differences among the groups in the number or percentage of motile rods or spirochetes after treatment.
3. There were no significant differences among the groups in total number of anaerobic bacteria after treatment. The number of sites in which black pigmented anaerobic rods (BPAR) were present and the number of sites in which Actinobacillus actinomycetemcomitans were present, were increasingly fewer in group I, II, III and IV. Sites containing Actinobacillus actinomycetemcomitans were no longer present after treatment in group IV.

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Periodontal conditions in young female students of the junior and senior high school in Sendai were surveyed using CPITN for a 10-year period. Over the 10-year period the prevalence rates in the subjects as a whole (13, 542) revealed a decrease in code 0 (health) and 3 (shallow pocket) and a great increase in code 2 (calculus). There were slight changes in code 1 (bleeding) and code 4 (deep pocket). The mean number of code 0 sextants decreased over ten years to a half of the initial year value. The number of code 1 and code 2 sextants increased, but that of code 3 and code 4 sextants decreased slightly.
All subjects were divided into three groups, i. e., mild, moderate and severe, according to their CPITN values, which were the totals of the code numbers of the sextants. The severe group underwent periodontal treatments as needed (WHO). In contrast to the large increase in the number of the moderate group, the number of the mild and the severe groups gradually decreased over the 10-year period. These results show that the great increase in the calculus group was replaced by a decrease in the healthy and the pocket groups.
There were 197 subjects in the severe group who underwent annual examinations for three years. The CPITN values in this group increased about twice as high as the first year value, and that reduced to the first CPITN value level at the last examination. The periodontal status of this group seemed to progress rapidly, however, even in the sever group recovery of periodontal status was achieved by early adequate treatment.

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The purpose of this study was to investigate the state of peripheral blood (PB) and gingivai crevicular fluid (GCF) polymorphonuclear leukocytes (PMNs) in periodontal patients.
Expression of C3 receptors (CR1 and CR3) on PB-and GCF-PMNs was determined in 29 periodontal patients (AP: 15, RPP: 14) and 52 healthy volunteers by flow cytometry after labeling with monoclonal antibodies. Intracellular and extracellular superoxide production by PB-and GCFPMNs was examined in the same subjects by flow cytometry with dichlorofluorescein diacetate (DCFH-DA) and luminol-dependent chemiluminescence. GCF IL-8 and IL-β A level were determined in the same subjects by the sandwich ELISA method.
Mean channel fluorescence for both CR1 and CR3 on GCF-PMNs was significantly higher in AP and RPP than in the healthy subjects. PMAstimulated luminol-dependent chemiluminescence of GCF-PMNs was significantly higher in AP and RPP than in the healthy sbujects. Intracellular superoxide production of GCF-PMNs was significantly lower in RPP than in the healthy subjects. The GCF IL-8 level (pg/30s) was significantly higher in AP and RPP than in the healthy subjects.
After initial preparation, mean channel fluorescence for both CR1 and CR3 on GCF-PMNs was lower than at the time of the first visit for most patients.
These findings imply that GCF-PMNs are activated in peridontal lesions and this is reflected on the focal stage of periodontitis.

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The purpose of this study was to develop a new method for analying jaw movements during sleep and to observe the jaw movements by using this apparatus. A two-dimensional (antero-posterior and lateral) jaw movement recording system was developed to assess bruxism during sleep.
The accuracy of this system was checked. The jaw movement data of 6 male and 1 female adult volunteers, 25 to 35 years of age (mean: 29.3 years) were examined for one night. In addition, data for masseter muscle activity were obtained by EMG.
The results obtained were as follows;
1) The accuracy of this system was equal to MKG in its ability to describe jaw movements in the horizontal plane.
2) This system was able to record jaw movements during grinding and clenching. In each subjects, grinding was divided into as many as three types according to the jaw movement pattern, but the patterns of jaw movements were similar in some types of grinding.
3) The clenching positions during sleep were centric occlusion and other lateral positions. Many clenching positions were observed on the locus of jaw movements of grinding patterns.
These findings suggest that our jaw movement recording system is able to record a jaw movements during sleep, and may be useful in assessing the mechanisms of acceleration of the progression of periodontal lesions by bruxism.

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We have been investigating the plaque-removing ability of different types of interproximal brushes. In this study, we prepared with cylindrical, tapered and conical type interproximal brushes. Twelve patients with adult periodontitis served as subjects in this study. They were instructed to use a toothbrush, and when the level of their O'Leary Plaque Control Record reached about 50%, they were divided into 3 groups. The patients in each group were instructed to use one type of interproximal brush for 3 weeks, and their plaque score was measured every week. All of the interproximal brushes used proved highly effective in removing interproximal plaque, and no significant differences were found between them. At third and forth week, the patients were directed to use the other types of interproximal brush for one week each. The plaque-removing ability of each brush was evaluated in a single blind cross-over trial on the basis of plaque scores at 3, 4 and 5 weeks. There were no significant differences between the brushes tested in mean plaque score at all of the sites examined, however, on the interproximal surface of the anterior teeth and on the lingual interproximal surface of all of the teeth examined, the tapered and conical interproximal brushes were significantly more effective in removing interproximal plaque than tha cylindrical brush.

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pellet containing minocycline for periodontal treatment (MINO pellet), the efficacy of inserting a MINO pellet int the gingival tissue around the periodontal pocket (intragingival administration) was studied clinically by determining MINO levels in the gingival tissue and periodontal pocket and morphologically observing the localization of MINO in the gingival tissue and the process of absorption of the MINO pellet after the gingival administration. The mean MINO levels in the gingival tissue were 40.5 μg/ml and 6.5 μg/ml, respectively, and the rate of detection was 100% for both sites. Fluoresence of MINO in the gingival tissue was observed until 14 days after the administration, suggesting that the MINO pellet is adsorbed or diminished from 14 days onward. The results showed that gingival administration enables secure long-term maintenance of high concentration of MINO in the gingival tissue and periodontal pocket.

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The purpose of this study was to analyze the relationship between symptoms and severity of periodontal disease, and to evaluate the effectiveness of screening for periodontal disease according to symptoms.
We assessed 486 subjects in Chengde-city, China age: 14-44 years; 211 males and 275 fem a (les). Plaque, calculus, gingival bleeding (GI), probing depth (PD), and attachment level (AL) were examined as clinical indices. And panoramic X -rays photos were taken to evaluate bone resorption. The questionaire concerned 18 symptoms considered to be related to periodontal disease.
The results are as follows:
1. The average number of symptoms per subject was 5.4 (minimum: 0, maximum: 16).
2. A significant correlation was found between number of symptoms and age, GI, PD, and AL. The strongest correlation was with AL (r=0.52), . - and the weakest correlation with GI (r=0.18). -.
Six of the 18 symptoms (e. g., occlusal pain, tooth mobility) were significantly correlated with AL. Occlusal pain was especially well correlated with bone resorption.
3. CPITN 2, 3 and CPITN 4 screening by the number of symptoms was evaluated. Sensitivity was 0.68 and specificity was 0.67 when the cut off level was 6.
4. When screening for severe periodontal disease using the 6 symptoms statistically correlated with AL was evaluated, sensitivity increased to 0.80.

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This study was carried out to assess the necessity and importance of plaque control, and investigated and compared the effect of plaque removal with the different types of toothbrushes and by different methods.
Ten adults, age 24 to 27 years, 6 males and 4 females, with clinically healthy periodontal tissue, were selected for the purpose of this study. They brushed by the scrubbing and rolling method using 14 kinds of toothbrushes which differed according to the forms of the bristle. Plaque scores were measured using the Plaque Control Record (O'Leary et al., 1972.) before and after toothbrushing.
The results were as follows:
The plaque removal rate for all teeth averaged 65.6%. The incisor plaque removal rate averaged 84.0%. The molar plaque removal rate averaged 54.1%. The region with the highest plaque removal rate was the buccal surface of the incisors (plaque removal rate : 62.5-100%), and the region with the lowest rate was the proximal surface of the molars (plaque removal rate : 10.8-61.7%).
The plaque removal rates tended to be lower for the molars than the incisors and on the proximal surfaces than the lingual, occlusal or buccal surfaces. Differences in plaque removal rates according to brush and toothbrushing methods were also noted.
The results suggested that the importance of the choice of appropriate toothbrushes and toothbrushing methods on an individual basis and the necessity of the systematic toothbrushing instruction in increasing the plaque removing effect.

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The purpose of this clinical study was to evaluate the efficacy of the combination of a liquid dentifrice containing triclosan, tranexamic acid, dipotassium glycyrrhizinate and sodium fluoride, a toothbrush with extremely tapered bristles and dental rinse containing cetylpyrisinium chloride and tranexamic acid in preventing and/or improving of periodontal disease. A placebo liquid dentifrice, a conventional toothbrush, and a placebo dental rinse were used as the control. Subjects were 60 adults who had periodontal disease but no serious oral or systematic diseases. They were divided into two equal groups and performed toothbrushing twice a day for four weeks. The results can be summarized as follows:
1) The test group was significantly superior to the control group in improving the plaque index p<0.01), gingival index (p<0.05), pocket d (epth p<0.05) and bleeding (p<0.05). (
2) Assessment of changes in bacterial flora revealed that the proportion of cocci increased significantly in the test group, but not significantly in the control group.
3) No adverse effects were observed in either group during this clinical study

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