The purpose of this study was to evaluate the effect of root coverage treatment with subepithelial connective tissue grafting. Forty-two sites of facial gingival recession in 10 patients (3 males and 7 females) were treated. Probing attachment level, vertical recession, horizontal recession, width of keratinized tissue, plaque index and bleeding on probing were assessedbefore surgery and then at 6 month intervals after surgery. Furthermore, we examined healing morphology on the rootsurface following subepithelial connective tissue graft treatment in dogs.
1) The mean root coverage obtained with subepithelial connective tissue grafting was73.95±32.27%.
2) The root coverage of upper tooth was significantly more effective than that with lower tooth. And the root coverage of anterior tooth was significantly more effective than that with posterior tooth.
3) There was no significant root coverage effect in width of horizontal recession, but a statistically significant root coverage effect was obtained in the depth of vertical recession.
4) The healing type of long junctional epithelium attachment was observed after subepithelial connective tissue grafting in a canine model, based on histological analysis.
The donor site wound healed very well without postoperativediscomfort. This subepithelial connective tissue graft survives due to the assistance of a double blood supply from the periosteum and labial flap. These results suggest that subepithelial connective tissue grafting represents a predictable procedure for improving gingival recession.

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The aim of the present study was to develop a rapid DNA probe method for the diagnosis of periodontitis that can be used in the dental clinics.
By using the DNA probe, we investigated the correlation between the occurrence of periodontal disease-associated bacteria: Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans, and the following clinical parameters: probing depth (PD) and bleeding on probing (BOP).
This method minimizes the use of water bath for ordinary hybridization and washing in order to shorten the total reaction time. Samples were hybridized with boiled DNA probe, and then washed thoroughly with 0.2×SSC/0.1% SDS at 75°C. Detection process could be completed within 2 hours. Detection level was more than 10⁴ bacterial cells/sample.
Subgingival plaque samples were taken from 468 sites in 55 patients with periodontitis (age 14-69 years old) before the periodontal initial therapy. After the periodontal therapy of scaling and root planing, 58 sites in 9 patients with periodontitis were bacteriologically and clinically evaluated.
When the DNA probe method was compared with the culture method, the accuracy was 88% for P. gingivalis, 67% for A. actinomycetemcomitans.
A statistically significant association was found between the detection of P. gingivalis and PD, BOP (x² test: p<0.001). A significant association was also shown between the detection of A. actinomycetemcomitans and PD in patients whose ages were 35 or older (x² test: p<0.001). The relationship between A. actinomycetemcomitans and BOP was not significant. The detection rate of A. actinomycetemcomitans was highest in teenagers. At shallow periodontal pocket sites (PD.≤3mm) in teenagers, no P. gingivalis was found, while 22% of the sites harbored A. actinomycetemcomitans. After the therapy, the proportions of P. gingivalis decreased significantly only in the clinically resolved sites (x² test: p<0.01). However, A. actinomycetemcomitans seemed to persist after the therapy.
The rapid DNA probe method appears promising as an efficient tool for rapid diagnosis, selection of treatment modalities, and microbiological evaluation of the treatment outcome.

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The purpose of this study is to investigate phagocytic activity and expression of surface receptor (in connection with phagocytic activity) (FcγR III and CR 3) on gingival crevicular fluid PMNs (GC-PMNs) in comparison of patients with adult periodontitis (AP) and healty subjects.
Peripheral blood PMNs (PB-PMNs) and GCPMNs were isolated from each subject (AP: n=10, healthy subjects: n=10). The analysis of phagocytic activity (phagocytosis and phagocytic index) and expression of surface receptor were performed. The effect of gingival crevicular fluid (GCF) supernatant on the phagocytic activity and the receptor expression on PB-PMNs were also investigated (PB-PMNs was incubated with HBSSCMF as control group). Phagocytic activity (phagocytosis and phagocytic index) and FcγR III expression of GC-PMNs were significantly lower than those of PB-PMNs in both groups. CR 3 expression of GC-PMNs were significantly higher than those of PB-PMNs in both groups. Phagocytic index of GC-PMNs in patients with AP was significantly lower than in healthy subjects, and FcγR III expression of GC-PMNs in patients with AP were lower than in healthy subjects. Phagocytic activity and FcγR III expression of PB-PMNs incubated with GCF supernatant was not statistically different from control group. CR 3 expression of PB-PMNs incubated with GCF supernatant was significantly higher than that of control group. These results demonstrate a partial decrease of phagocytic activity of GC-PMNs in patients with AP compared to that of healthy subjects. The above suggest there is little that influence of GCF supernatant on phagocytic activity of PMNs.

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The oral mucosa became inflamed as a result of functional impairment and morphological degeneration caused by a variety of etiologic factors. In this study, the experimental degradation of the mucosal epithelial cells was investigated by treatment with a typical inflammatory stimuli. Human gingival epithelial cells obtained from clinically healthy gingiva were cultured for 24 or 48 hours and treated with 2.5ng/ml and 25ng/ml interleukin-1. β (IL-1. β). The following results were obtained. Light microscopy did not reveal any marked change except for slight widening of the intercellular space in the treated group. Ultrastructual examination, however, showed flattened cells, widened intercellular space, and degenerated and partially lost cell processes in the treated group. The actin filaments oriented in all directions in the cytoplasm in the control group. In the treated group, they had become aggregated or formed bundles and lost their original morphology as stress fiber. In addition, expression of the cell membrane lining proteins, Vinculin and Focal Adhesion Kinase (FAK), had diminished in number or disappeared. Immunohistochemical study with antibodies for Vinculin and FAK showed that they were localized on the cell membrane in the control group, whereas in the treated group, they were diffusely distributed in cytoplasm around the nucleus. These findings might afford additional experimental morphological bases to the impaired gingival epithelial function by inflammatory stimuli.

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This study was performed to clarify the in vivo damage to periodontal tissue induced by lipopolysaccharide (LPS) from Actinobacillus actinomycetemcomitans Y 4 and Porphyromonas gingivalis 381, which penetrate the junctional epithelium. Each LPS solution (5 mg/ml) was continuously dropped into the gingival sulcus of the lower first molar of a Lewis rat for 30min every 24h. The animals were sacrificed 30min after the 1st, 3 rd, 7th, 10th and 15th administration and their mandibles were examined histopathologically and histomorphometrically (n=25 in each group). A gradual increase in inflammatory findings was observed in both LPS groups. However, A. actinomycetemcomitans LPS induced more marked inflammation and degeneration of periodontal tissue. Loss of connective tissue attachment and rete peg elongation were significantly greater in rats administered with A. actinomycetemcomitans LPS compared to those administered with P. gingivalis LPS. Degeneration of junctional epithelium and subepithelial connective tissue was found at the 1st and 3rd administrations. At the 7th and 10th administrations, epithelial cells and collagen fibers were detached from root surfaces. Rete pegs showed deep invasion toward alveolar bone and epithelial detachment downward migration. At the 15 th administration, osteoclastic bone resorption was in some cases observed on the alveolar bone crest in the A. actinomycetemcomitans LPS group. These findings suggest that A. actinomycetemcomitans LPS had a greater effect on periodontal tissue destruction than P. gingivalis LPS.

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The purpose of this study was to compare the plaque-removing effect of a newly developed ultrasonic interdental brush with a conventional manual interdental brush.
The newly developed ultrasonic interdental brush was enhanced by using a manual interdental brush with a high intensity wire attached to the handpiece of an ultrasonic scaler device. An interdental space model was prepared to be 3 mm of interspace between two acrylic plates, and artificial plaque was coated onto these plates. The artificial plaque was composed of starch and color paints. In some experiments, these plates were polished by two types of polishing papers, # 320 (coarse) and # 1000 fine). Ultrasonic and conventional interdental brushes were inserted between the two plates and moved vertically for 5 and 10 seconds with various power ranges. The plaque-removing effect was evaluated by determining a gray value gained from computer-image analysis.
We found that the ultrasonic interdental brush showed a significantly lower value than the manual brush. Similar results also were obtained when operating time, power range of the apparatus and roughness of the plates were changed. These findings suggest that the ultrasonic interdental brush can remove plaque more effectively than the manual brush, and that there is a possible clinical use for the ultrasonic interdental brush.

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In order to clarify the roles of Langerhans cells (LCs) associated with host defence mechanisms in nifedipine (NF) -induced gingival overgrowth, the intraepithelial distribution and density of LCs in tissues from the following four groups were examined. Using a rabbit anti-human S-100 protein antibody assay, gingival tissue samples from patients with NF-induced gingival overgrowth (NF-responders, R group) were compared with those from NF-nonresponders (NR group), proliferative gingivitis patients secondary to the presence of dental plaque (ND group) and systemically healthy subjects (Ctrl group). Five patients in each group were randomly selected and all gave informed consent to take part in this study. Gingival tissue samples were carefully taken during periodontal flap surgery or tooth extraction and the serial specimens were embedded in paraffin and routinely processed. The specimens were immunostained with anti-S-100 protein polyclonal antibody followed by histological analysis of the positive cells in gingival epithelium. The S-100 positive LCs were defined as the total S-100 positive cells minus those positive cells identified with Schmorl stain. Histologically, the S-100 positive cells from the specimens in all groups were scattered in both the basal and the spinous layers. The percentages of positive cells per total epithelial cells in all groups were increased in the following order, R>ND>NR>Ctrl. Statistically significant differences were seen between the groups, R and ND (p<0.05), R and NR (p<0.01), ND and NR (p<0.05), R and Ctrl (p<0.01), and ND and Ctrl (p<0.05). On the contrary, no significance was seen between the groups of NR and Ctrl. The gingival epithelium investigated in this study was divided into two groups, S-100 protein positive LC-rich area and S-100 protein positive LC-poor area in each group. CD3-positive cells appeared to be greatly infiltrated in the connective tissue beneath the epithelium accumulated by LCs. This tendency was remarkable especially in the R group. Similarly, the connective tissues examined were divided into two regions, the densely and/or sparsely infiltrated region by inflammatory cells. In comparison with the frequency of S-100 positive LCs in the connective tissues beneath each region, a significant relationship was seen only in the ND group (p<0.05). Also, the frequency of LCs in the epithelium of the R group among the sparsely infiltrated regions was significantly higher than any other groups (p<0.01). Considering that the S-100 positive LCs were significantly increased in the oral epithelium and that a large number of CD 3-positive cells was infiltrated beneath the epithelium, our findings suggest the enhancement of the pathophysiological roles of LCs and CD 3-positive cells in NF-induced gingival overgrowth.

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Tooth brushing machines have been used mainly to study the effects of toothpaste on the abrasion of human teeth and dental materials. These tooth brushing machines have essentially horizontal and vibratory actions, which do not necessarily reproduce the same motions as those of clinical brushing motions. So, we developed a new brushing machine called a brushing simulator, and evaluated its reproducibility of results on plaque removal. To obtain clinical data on plaque removal and brushing pressure, weperformed a clinical study using ten subjects, and newly designed toothbrushes, A: nylon bristles, 0.152mm in diam (eter, round end, 9.5mm in length, 4.59kg/cm² in the hardness of total bristles; and B: nylon bristles, 0.254mm in diameter, round end, 9.5mm in length, 12.01kg/ cm² in the hardness of total bristles). Eachsubject performed their scrubbing method. We calculated the stroke width, the stroke speed and the brushing time by a handy video camera. The tooth brushing pressures were determined by modified Watanabe's method. We put these data into the brushing simulator, and calculated the plaque removal rate, then compared the clinical data and the simulator data on plaque removal rate. The average percentages of plaque removal by the simulator and by the subjects using different toothbrushes (A and B) were asfollows:
1) 77.9±19.4% by subjects with brush A.
2) 92.1±4.2% by brushing simulator with brush A.
3) 92.4±18.0% by subjects with brush B.
4) 90.4±3.4% by brushing simulator with brush B.
It is suggested that this newly designed tooth brushing simulator has a high reproducibility and is useful for evaluating plaque removal.

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The purpose of this study was to investigate the interproximal plaque removing ability of toothbrushes in patients with periodontal disease . Two different bristled toothbrushes, ripple bristled and flat bristled toothbrushes were used.
Thirty four (8 males and 26 females) periodontal patients in maintenance phase were divided into three groups. First group was given ripple bristled toothbrushes, second group was given flat bristled toothbrushes, and third group was given flat bristled toothbrushes and interproximal brushes. The brushing method and time were not regulated . Probing depth, gingival index and bleeding on probing were examined at baseline and after 3 weeks . Plaque score was measured every week . Ripple bristled toothbrushes had better ability to remove interproximal plaque than flat bristled toothbrushes, but the additional use of interproximal brushes with flat bristled toothbrushes showed the highest ability. The ripple bristled toothbrushes removed plaque more effectively at the narrow proximal surface than at the open wide surface.

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The purpose of this study was to evaluate the effect of a newly developed toothbrush on gingival inflammation and plaque accumulation following periodontal surgery. Forty subjects with adult periodontitis participated in this study, and each subject had two sites receiving similar surgical treatment. Twenty-eight of the forty subjects were dressed after surgery (group A) while the others were not (group B). In both Case groups, the two treated sites in each patient were randomly assigned either as a test site or as a control site. For daily care of the test sites, patients were instructed to brush with a newly developed toothbrush and to use an antimicrobial rinse containing 0.004% benzethonium chloride for 15 days beginning the day of dressing removal in group A, and beginning the day after surgery (baseline) in group B. For care of control sites, patients were instructed to use only the antimicrobial rinse for during the same period. The clinical parameters for assessing plaque accumulation and gingival inflammation (GI) were observed at baseline, and the reafter at day 7 and day 15. Soft tissue trauma caused by toothbrush usage were also checked at day 7 and day 15.
In group A, mean redness and swelling scores for test sites were lower than those for control sites, and these differences were significant statistically at day 15 (redness: p<0.01, swelling: p<0.05). Similar findings were also observed in group B, and moreover, GI scores markedly were improved in test sites as compared to control sites at both day 7 and day 15 (p<0.05). On the other hand, mean Plaque Control Recond (PCR) scores for test sites significantly decreased during the study, whereas control sites did not show a noticeable change in the parameter, thus the differences between both sites were significant (group A: p<0.01 at days 7 and 15, group B: p<0.01 at day 15). In addition, soft tissue trauma caused by this newly developed toothbrush was not observed during the experimental period. In the present clinical trial, it was confirmed that in the early stage of postsurgical healing, plaque control using this toothbrush as an adjunct to ordinary antimicrobial rinse was significantly more effective in the improvement of clinical inflammation and plaque reduction as compared to using the antimicrobial rinse only.

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A periodontal screening and recording (PSR) system was used to examine the periodontal disease state in a mass oral examination. The results of the PSR were compared with those from a selfevaluation by questionnaire survey. The patients were 100 newly-enrolled participants in dental screening at a certain factory (74 males and 26 females: average age, 49.1 years). The oral cavity was divided into six regions for the PSR evaluation, and the results of the PSR were classified into 5 codes. Plaque adhesion was examined for plaque control record (PCR) evaluation. Questionnaire survey items included : identification of periodontal disease, understanding of periodontal disease, brushing method, brushing frequency, brushing time, and the presence or absence of scaling. A statistical relationship between the PSR codes and both the PCR points and the questions was examined by the x² test and F-test. Code 3 was the most common in PSR evaluation in this study. The PCR scores of Code 3 and Code 4 were higher than Code 1 (p< 0.05). The results of the identification of periodontal disease were at a higher ratio following the Code (p <0.01, p< 0.05). These results indicate that PSR can serve as a screening, evaluating and recording tool for periodontal disease and will be useful for the early detection, early treatment, and management of periodontal diseases, especially when supplemented with self-evaluation by questionnaire survey.

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