In order to better understand the contribution of salivary proteins to the formation of dental plaque, the localization of salivary proteins in deposits on human teeth was investigated by an immunohistochemical method.
Caries free teeth (35 cases) were selected from generally healthy volunteers who had been undertaking orthodontic therapy with the necessity of exodontia. Before extraction, thoroughgoing cleaning was performed, and toothbrushing suspended from one to 7 days. The extracted teeth were fixed with 1% glutaraldehyde, and buccolingually divided into two pieces. The samples were embedded in paraffin wax or LR white resin® and were demineralized with EDTA.
Immunoperoxiedase staining with the rabbit antiserum against parotid saliva and/or whole saliva (streptavidin-biotin method) showed the localization of salivary proteins in the film surrounding the tooth crown after one day suspension of toothbrushing. On and after the second day, the localization was also investigated in the dental plaque which gradually increased following proliferation of bacterial colonies.
By immunoelectron microscopic investigation, gold particles were recognized in the thin film and interbacterial matrix.
These immunohistochemical observations indicate that salivary proteins contribute not only to the formation of acquired pellicle but also the maturation of dental plaque by providing a suitable circumstance for bacterial growth.

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The purpose of this study was to investigate the ultrastructural localization of glycoconjugates in the healthy gingiva of the dog using the Lectin gold complex staining technique (Con-A, WGA, SBA, PNA), which specifically recognizes sugar residues, High iron diamine-thiocarbohydrazide-silver proteinate (HID-TCH-SP) staining technique, identified as a heparan sulfate and immunohistochemical staining technique (HepSS-1) with recognition of an epitope present in heparan sulfate glycosaminoglycan (HS-GAG). WGA-gold particles, HepSS-1-gold particles and HID-TCH-SP stain deposits were distributed on cell membranes and heterocromatin was distributed in epithelial cells. In addition, Con-A, WGA, HepSS-1-gold particles and HID-TCH-SP stain deposits were detected on cell membranes in all epithelial cell layers except the keratinized layer. On the other hand, SBA and PNA-gold particles were localized inside the nuclei of basal and spinous cells. In addition, particles were detected within the apical cytoplasm, on surface membranes of the coronal portions of spinous cells. Con-A, HepSS-1-gold particles and HID-TCH-SP stain deposits were also detected in basement membranes.
The heterogenous distribution of glycoconjugates suggests that they play an important role in cytodifferentiation and the artchitectural integrity of epithelial cells.

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A major outer membrane protein (the 75-kDa protein) from Porphyromonas gingivalis 381 has recently been purified and characterized. In this study, the 75-kDa protein was further investigated from molecular genetic and immunological aspects. To clone a gene for the protein, its N-terminal amino acid sequence was analyzed and DNA probes based on this sequence were synthesized. Using the probes, a recombinant plasmid clone carrying a single 4.2 kb BamH I fragment was isolated from pUC 19 libraries of P. gingivalis 381. The cloned 4.2 kb BamH I fragment was transferred to the bacteriophage T7 RNA polymerase/promoter vector system which produced a slightly larger 77 kDa protein immunoreactive to the antibody against the 75-kDa protein. Genomic Southern analysis revealed a single copy of the 75-kDa protein gene per genome among all P. gingivalis strains tested, and that no homologous genes were present in the other black-pigmented Bacteroides species. The 75-kDa protein gene, therefore, may be useful as a specific DNA probe to classify or detect this organism.
The 75-kDa protein was shown to be immunologically species-specific when immunoblot analysis was done using whole cell lysates from the same strains and the antibody against the 75-kDa protein described above. None of the species, except for P. gingivalis strains, showed any immunoreactivity to the 75-kDa protein. To detect specific antibodies against the 75-kDa protein, immunoblot analysis with sera from periodontal patients and healthy subjects was done. As a result, 65.6% of adult periodontitis patients and 100% of rapidly progressive periodontitis patients were found to have specific antibodies against the 75-kDa protein, while the sera of gingivitis patients and healthy subjects did not show positive reactions to the protein. These findings suggested that the 75-kDa protein is an immunologically species-specific and immunodominant surface antigen. The etiology of periodontitis, especially rapidly progressive periodontitis, may be related to P. gingivalis.

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The purpose of this study was to investigate the relationship between premature contact at the centric slide and initiation of occlusal trauma. In this study, the distance between the retruded contact position (RCP) and intercuspal occlusal position (ICP), the distance from RCP to ICP in the protrusive or lateral direction, and the vector value of two directions were measured using a mandibular position-fixing device, which enabled the mandibule to be guided and fixed in the RCP, and the study model mounted on an articulator. The subjects consisted of 20 patients with adult periodontitis, who had been diagnosed as having premature contact in the RCP and with (n=10) or without (n= 10) occlusal trauma.
The following results were obtained:
1) The distance from RCP to ICP was significantly longer in the group with occlusal trauma as compared to the group without occlusal trauma (p<0.05). 2) The distance from RCP to ICP in the protrusive direction in the group with occlusal trauma was 1.91±0.10 mm while in the group without it was 1.62±0.17 mm. The value of the protrusive direction was significantly longer in the group with occlusal trauma than in the group without occlusal trauma (p<0.05). However, the value of the lateral direction did not differ significantly between the two groups.
3) The vector value of two directions was significantly longer in the group with occlusal trauma than in the group without occlusal trauma (p< 0.05). These results indicate that premature contact at the centric slide may play an important role in triggering occlusal trauma and that the distance from RCP to ICP in the protrusive direction is involved in the initiation of occlusal trauma.

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Fibronectin (FN) plays important roles in wound healing processes, such as cell adhesion, cell chemotaxis and cell differentiation. Recent studies have revealed that FN treatment accelerates the adhesion of fibroblasts onto the dental root surface both in vivo and in vitro. In wound healing, FN acts as a substrate for blood coagulation factor XIII, forming covalent linkages with fibrin and collagen. There fore, it has been suggested that factor may promote the attachment of FN onto dentin collagen. In this study, we investigated the localization and level of FN attachment on dentin surfaces under various conditions, i. e., 1) root plaing only (N), 2) root planing and citric acid treatment (C), 3) root planing and factor XIII treatment (N XIII), 4) root planing, citric acid and factor XIII treatment (C XIII). Immunoelectron microscopy was performed with human dentin blocks implanted under mucoperiosteal flaps on the maxillary palatal site in rats. One hour after implantation, the specimens were taken out and the localization of FN on the dentin surface was examined immunohistochemically. Adsorption of FN onto dentin was determined using ¹²⁵I-labeled human plasma FN and dentin blocks. In another experiment, the effect of the plasma component on the adsorption of FN was examined by incubating ¹²⁵I-FN with FN-free human plasma. Immunoelectron microscopy showed the accumulation of FN on dentin surfaces pretreated with factor XIII (group N XIII and C XIII), while this accumulation was not marked on dentin in the groups with root planing only (N). Likewise, the amount of 125I-FN binding was estimated to be greater in groups N XIII and C XIII than in groups N and C. The adsorption of FN was inhibited when FN- free plasma was added to the incubation, medium possibly due to certain inhibitors in the plasma. These results suggest that blood coagulation factor XIII enhances the adsorption of FN onto dentin and that the effect of this factor merits further investigation aimed at clinical application in periodontics.

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We conducted a study to clarify the role of complement on superoxide production (Chemiluminescenceresponse: CL response) and phagocytosis of human neutrophils against Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis Pg and Fusobacterium nucleatum (Fn). We also determined the types of complement receptors participating in those responses.
CL response was measured with a Lumiphotometer. Anti-human CR 1 and anti-human CR 3 antibodies were used to determine the type of complement receptor. The activities of phagocytes were estimated by counting the cells and the bacteria on stained smear specimens.
The complement dependency of the CL response was examined and the complement dependent portion of the CL response was greater in Aa (90%) and Fn (75%) than in Pg (50%), as compared with the intensity of the CL in the presence and absence of complement. Results from the blocking effect of CL, with the presence of either anti-CR 1 or anti -CR 3 antibody, showed both CR 1 and CR 3 were available in the ratio of1: 3 in the CL response against Aa and Fn, while only CR 3 was accessible in the response against Pg.
In the phagocytosis experiments, CR 3 was proven to be the only receptor which could be utilized by the 3 genera of bacteria.
These data suggest that complement and its C 3 bi receptor have an important role in superoxide production and neutrophil phagocytosis.

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This study was designed to evaluate the effect of the guided tissue regeneration technique using defatted decalcified freeze-dried bone matrix powder on the healing of furcation defects.
Three mongrel dogs were used. Class III furcation defects were produced in the 3 rd and 4 th lower premolars. Dogs were treated by two different surgical methods. On the control side, the guided tissue regeneration technique alone was used, and on the experimental side, the guided tissue regeneration technique plus bone graft were used.
Fourteen weeks after the operation the dogs were sacrificed, and histopathological studies were performed. The results were as follows;
I. Control side
1. Connective tissues had filled the furcation defects.
2. Minimal amounts of bone regeneration were observed at the bottom of the furcation defects.
3. Formation of new cementum was observed all around the fornix of the furcation. II. Experimental side
1. Furcation defects were completely covered by regenerated bone which was separated from the root surface.
2. Formation of new cementum was observed all around the fornix of the furcation.
3. A functionally oriented periodontal ligament had become reestablished in the apical portion.
These findings suggest that the guided tissue regeneration technique with bone grafting may increase bone regeneration of furcation defects.

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Cetylpyridinium chloride (CPC) has been widely used in oral-care products but its antimicrobial effect decreases remarkably in the aqueous solution of a nonionic surfactant.
The purpose of this study was to assess the bactericidal effect of CPC on Porphyromonas gingivalis P. gingivalis in an aqueous solution of Poly oxyethylene (60) hydrogenated castor (oils HCO-60) as a nonionic surfactant.
With an increasing HCO-60 concentration, the bactericidal effect of CPC and the adsorption of CPC on P. gingivalis cells decreased remarkably.
Furthermore, a CPC-based dental rinse without a nonionic surfactant showed a higher antimicrobial effect on oral bacteria than that with such a surfactant.
It was concluded that a CPC-based dental rinse without a nonionic surfactant is effective.

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The purpose of this study was to investigate the origin of chondroitin sulfate proteoglycans (chondroitin 4 sulfate proteoglycan, C 4 S-PG, chondroitin 6 sulfate proteoglycan, C 6 S-PG) in the gingival crevicular fluid (GCF) of dogs with healthy periodontal tissues.
Chondroitin sulfate proteoglycans obtained from gingiva, serum and GCF were separated by SDS -PAGE, blotted onto nitrocellulose membranes by Western blotting technique, and immunostained with specific antibodies (3-B-3, 2-B-6) against chondroitin sulfate proteoglycan isomers.
The major bands of C 4 S-PG in GCF samples yielded an electrophoretic profile similar to that of serum. However, the GCF samples showed a few minor migrating bands which were not detectable on serum samples, coincident in electrophoretic mobility to those of gingival samples.
The distribution profile of C 6 S-PG on electrophoresis was similar to that of C 4 S-PG in all samples.
These observations show that chondroitin sulfate proteoglycans detected in GCF samples could be derived partly from gingiva as well as serum.

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The purpose of this study is to evaluate the ultrastructure of cell attachment and newly synthesized collagen fibers to the root surface.
Root slices were prepared from extracted periodontally-diseased teeth. After ultrasonic scaling, root slices were divided into two treatment groups : 1) root planing (RP) 2) root planing followed by treatment with citric acid (RP+CA). The root slices were placed in 35-mm Petri dishes and seeded with human fibroblasts derived from periodontal ligament in DMEM at an initial density of 4 x 10⁵ cells/dish. After incubation for 10 weeks, we examined the ultrastructure of the interface between the root surface and cells by transmission electron microscopy.
The results obtained were as follows:
1) In the RP group, the gap between the root surface and the fibroblasts was narrow, where no collagen fibers were observed. These fibroblasts attached to the root surface beyond the electron dense material.
2) In the RP+CA group, the gap between the root surface and cells was wide, and new collagen fibers had attached to the root surface.
3) The features of cell attachment and formation of collagen fibers on treated cementum were the same as on treated dentin.
The results of this investigation suggest that treatment with citric acid leads the direct attachment of new collagen fibers to the root surface.

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The purpose of the present study was to observe the localization and distribution of certain plaque bacteria, including periodontopathic species, in human periodontal pockets.
After obtaining voluntary consent from patients, teeth and their surrounding periodontal tissue with advanced adult periodontitis were extracted carefully so as not to changing the structure of the periodontal pockets. The teeth were processed into serial sections, stained with Brown-Brenn modified Gram stain and immunohistologically using labeled streptavidin biotin (LSAB method) with specific rabbit antibodies against 15 plaque bacterial species including periodontopathic bacteria. The localization and distribution of the bacterial species in huamn periodontal pockets were observed under light microscopy.
Small aggregates of Porphyromonas gingivalis were scattered throughout the periodontal pockets, and the numbers of these aggregates exceeded those of other bacterial species. Eikenella corrodens, which formed small clumps, was located mainly close to root surfaces in the middle and deep pocket zones. Fusobacterium nucleatum also consisted of small clumps in the middle and deep pocket zones, but its localization was in the unattached plaque area.
On the other hand, Campylobacter rectus generaly formed large clumps in the middle and deep pocket zones, and was located close to both the root surface and the epithelial surface in periodontal pockets. Treponema denticola was observed over the unattached plaque area located mainly in the middle pocket zone.
As had been expected, we actually observed that respective bacterial species had individual adhesion, colonization and growth properties in human periodontal pockets.

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The clinical and microbial effects of Periocline® administration in periodontal pockets, in combination with scaling, were examined in patients using two delivery systems and root planing. Three different sites, one in each quadrant, were randomly selected in each of 10 periodontal patients participating in this study. Each patient received the following treatment: Periocline® administration four times at one-week intervals in combination with scaling at one site (group A), Periocline® administration four times at one-week intervals without scaling at the second site (group B), and root planing alone at the third site (group C).
The results obtained were as follows:
1. The clinical findings, with the exception of the plaque index, showed greater improvement in groups A and C than in group B throughout the entire observation period.
2. Phase contrast microscopy, revealed both a lower total bacteria count and lower percentage of spirochetes and motile rods in groups A and C than in group B throughout the entire observation period .

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The purpose of this study was to evaluate the effect of initial treatment (tooth brushing instruction, scaling, root planing, simple occlusal adjustment) on early onset periodontitis. The 29 patients were 13 to 35 years old at the first visit and consisted of 12 males and 17 females. Clinical parameters were obtained at the time of the baseline examination and at the end of the initial treatment. Erythema and swelling of the gingiva, bleeding, and pus discharge from the gingiva decreased markedly after the initial treatment as compared with the pre-treatment findings. Probing depth and tooth mobility also decreased after the initial treatment. Many periodontal pockets below 6 mm at the baseline examination were improved to less than 4 mm by the initial treatment, whereas many periodontal pockets deeper than 7 mm at the baseline examination were deeper than 5 mm at the end of the initial treatment. Patients in their thirties were not so improved in pocket depth as patients in their teens and twenties.
The results of the present study indicate that early detection is important and that initial treatment might be effective for early onset periodontitis as well as adult periodontitis. Further more, in the event of initial treatment not being effective, more positive measures are needed.

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The present study was designed to investigate the possibility of using ultrasonic cavitation as a new method of plaque control. For this reason, we developed and tested 20 different types of tips capable of generating ultrasonic cavitation around the oscillating tips in water and removing artificial plaque deposited on the surface of artificial teeth surface. Each tip was distinguished by its position and/or angle of curvature. The following results were obtained by using these tips. First, the position and angle of curvature of affected the amplitude and the area of an artificial plaque removed. Second, there was no significant correlation between the angle of curvature of a tip and the plaque removal area. Third, the area of plaque removal increased as the amplitude of the tip increased to a constant value (approximately 30μm) and reached a plateau. Lastly, plaque removal was most effective with a distance of 2-3 mm between the tip and the artificial tooth surface. At greater distances, the plaque removal area was decreased. Some of the tips were capable of removing of plaque up to 6 mm in diameter.
These findings suggested that improvements in the tips and the device used in this study may enable effective plaque control.

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We have been investigating the plaque-removing ability of different types of interproximal brushes and have reported on the effect of bristle length and bristle diameter. In this study, we assesed the effect of number of bristles. An interproximal brush with 700-800 bristles, the same as used in our previous reports, and interproximal brushes with 70% and 60% of its number of bristles were prepared. Sixteen patients with adult periodontitis were used in this study. They were instructed to use a toothbrush and when the level of their O'Leary's 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 effectiveness in removing interproximal plaque, and no significant differences were found between the individual interproximal brushes.

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The purpose of this study was to evaluate the clinical effect of a new dental rinse containing 0.02% Cetylpyridinium chloride and 0.05% Tranexamic acid on the prevention of periodontal disease (prevention of plaque and improvement of gingivitis). The rinse was formulated without nonionic surfactant so as to improve the efficacy of Cetylpyridinium chloride.
The study was conducted using a double-blind design with 63 healthy subjects for four weeks. Gingival index (GI) and plaque index (P1I) on 62/4 /4/26 were examined at baseline, and at 1, 2 and 4 weeks after treatment.
The following results were obtained;
1. Improvement of PlI was statistically higher in thc tcst rinse group than in the placebo rinse group for all examination periods (P<0.001).
2. Improvement of GI was statistically higher in the test rinse group than in the placebo rinse group for all examination periods (P<0.01).
3. No adverse effects were observed during the study in any of the subjects.
The results indicate that a new dental rinse containing Cetylpyridinium chloride, as an anti -microbial agent, and Tranexamic acid, as an anti -inflammatory agent, has superior effects in preventing periodontal disease (prevention of plaque and improvement of gingivitis).

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In recent years, antibiotics have been as a local drug delivery system on periodontal pockets, but many problems have been noticed, such as MRSA and so on. Chinese traditional medicine has been getting satisfactory clinical result in the long term. The purpose of this study was to develop a new local drung delivery system using mixo-extract form “Kinginka” and “Rengyo” that are one of the antipyretic and antidotal crude drugs. In consequence we have noted the high anti-bacterial and anti-inflammatory actions by the mixo-extract. The mixo-extract was injected into periodontal pockets. Clinical parameters of inflammatory periodontal tissue were examined for the effect of and -inflammatory actions . Comparisons of the clinical parameters between test sites and control sites showed significant improvement in the gingival crevicular fluid and bleeding on probing in the test sites (P<0.05).

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Various reports have demonstrated the efficacy of electric tooth brushes on oral hygiene, and have also shown that the efficacy of manual tooth brushes on oral hygiene depends on the form and, the shape of the brushing surface, its hardness and the brushing method. We investigated the effect on oral hygiene of electric tooth brushes with forward or backward and eccentric vibrations whose brushing surface and vibration rate were different. This study included 8 subjects with clinically healthy gingivae (4 men and 4 women, aged 23-26 years with a mean of 23.8 years). Electric tooth brushes with forward and backward vibrations (vibration range, 2.0 or 2.5 mm) or eccentric vibrations (17 or 26..) were prepared. They had different fiber tip length intervals (1.5 or 2.0 mm) and rotation rates (2000, 2500, 3000/min). Each was used for 3 minutes per oral cavity, and the rate of plaque removal was then determined. The electric tooth brush with forward or backward vibrations, which yielded the highest rate of plaque removal, had a fiber tip length interval of 1.5 mm, vibration range of 2.0 mm and rotation rate of 2500/min. The electric tooth brush with eccentric vibrations, which provided the highest rate of plaque removal, had a fiber tip length interval of 1.5 mm, amplitude of 26.. and rotation rate of 3000/min. The results suggest that even with the electric tooth brush, the brushing method, the shape of the brushing surface, amplitude and rotation rate have a great influence on the rate of plaque removal.

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We studied three patients with gingival hyperplasia in order to develop methods of diagnosing and preventing this problem.
Although the conditions of patients taking Nifedipine were poor, those of patients who changed from Diltiazem to Celiprolol, and from Nifedipine to Diltiazem were significantly better. Thus, changing medication may reduce the gingival hyperplasia caused by calcium antagonists. We also found that plaque control was effective and necessary in controlling this condition.

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