The purpose of this study was to examine the avidity of IgG antibodies for the surface antigens of Porphyromonas gingivalis in sera from patients with adult periodontitis. The antigens used were whole cells, lipopolysaccharides (LPSs), and fimbrial preparations of non-invasive P. gingivalis ATCC 33277 and invasive 16-1. The serum IgG levels for P. gingivalis antigens were measured by enzyme linked immunosorbent assay (ELISA) before and after periodontal initial preparation. Serum IgG avidity was measured by diethylamine dissociation ELISA.
Serum IgG titers for whole cells of 16-1, LPS and fimbria antigens from both P. gingivalis strains were significantly higher in the patient than in the control group, whereas IgG values for the avidity index against antigens from patient sera were significantly lower than those from control sera. Although we found statistically significant decreases in IgG antibodies in patient sera after initial preparation, the IgG avidity index for fimbria from the invasive 16-1 strain in patient sera increased. The present study showed that IgG antibodies in patients were more responsive to invasive P. gingivalis 16-1 than to non-invasive ATCC 33277.
The patient sera with high IgG titers demonstrated low avidity index values, suggesting that IgG immune responses in patients play no role in colonization inhibition or elimination of P. gingivalis. The data indicate that periodontally healthy individuals have highly functional antibodies, which may protect against P. gingivalis colonization. Our findings suggest that the capacity to produce functional antibodies is lower in the patient group than in the periodontally healthy group, but that the production of functional antibodies is induced by initial preparation.

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To establish conditions for observing rat hard tissue by confocal laser scanning microscopy (CLSM), suitable specimens of bone and teeth were observed three-dimensionally after staining with various fluorescent labeling agents. Rats were injected subcutaneously, intramuscularly, intraperitoneally or intravenously with calcein. Two days later, the animals were euthanized and subjected to perfusion fixation. Their mandibles were dissected out and embedded in epoxy resin for preparation of undecalcified sections 500, μm in thickness. These specimens were examined by CLSM, using barrier filters for wavelengths of 535 nm (CH1) and 610nm (CH 2), at an excitation wavelength of 488nm. Rats were given calcein, tetracycline or alizarin red or combinations of these fluorescent dyes at various concentrations, then simultaneously treated and examined by CLSM. Calcein was easily detected using the CH 1 and CH 2 when administered at 1 or 2mg per 100g body weight. Alizarin red was detected using the CH 2 when administered at 4 or 8mg per 100g body weight. Tetracycline was detected using the CH 1 and CH 2 when administered at 4 or 8mg per 100g body weight. When calcein was injected intravenously, the labeling line was narrower and more strongly fluorescent than the labeling line after subcutaneous injection. The labeling line observed after intraperitoneal and intramuscular injection was intermediate in intensity between those after intravenous and subcutaneous injection. Double fluorescent staining with calcein at 2mg and alizarin red at 4mg per 100g body weight were found to be suitable for CLSM of mandibular specimens.
Under these staining conditions, the dentin and outer zone of the supporting bone of the alveolar process showed a regular labeling pattern, whereas the alveolar bone proper adjoining the periodontal membrane displayed an irregular labeling pattern. Bone lacunae and their canaliculi were observable

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Clinical procedures for subgingival plaque control include mechanical debridement and local chemotherapy. Minocycline-HCl paste, one of several drugs used for local chemotherapy, contains 2% minocycline-HCl. After administration of minocycline-HCl paste, minocycline was detected until 168 h in the periodontal pocket. A study was conducted to evaluate the effect of minocycline-HCl paste on human dentin surfaces and cell attachment in vitro. The dentin surfaces were treated with sandpaper, which matched planed surfaces, then treated with different concentrations of minocycline-HCl paste solution (test group) and with phosphate buffered saline (control group) for 7 days. After both treatment, cultured periodontal ligament cells were incubated on each sample for 72 h. Finally, the dentin surfaces and cell attachment were evaluated by scanning electron microscopy, which revealed that surfaces in the test group were cleared of the smear layer, whereas the surfaces in the control group retained the smear layer. The test group surface showed more cell attachment and growth than the control group surface. Therefore we conclude that administration of minocycline-HC1 paste removed the smear layer and increased the attachment of cells to the dentin surface.

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The pH of the periodontal pocket is related to the microbial flora and the inflammatory process in periodontal tissues. Many investigators have studied the pH in gingival crevices or periodontal pockets using different methods which have yielded a variety of results. In order to measure the pH directly in periodontal pockets, a periodontal probetype antimony micro-electrode (AT) was designed. The antimony electrode is not fragile and is thus convenient for pH recording, but it has been reported to be inaccurate in the presence of organic reducing agents. The purpose of this study was to evaluate the accuracy of the AT in comparison with a conventional glass electrode (GL) in vitro.
The AT tip diameter was 0.5 mm, and its form and size were similar to those of the conventional periodontal probe. Prior to the pH measurement, the AT was calibrated using standard buffers of pH 4 and 7, while the GL was calibrated with pH 4, 7 and 9 buffers. The two electrodes were put in the same test solution to give the pH readings simultaneously. Either HCl or NaOH was gradually added to the standard solutions to cover the pH range of 4.0-9.2, and the pHs given by the GL and the AT were continuously recorded. Then, the pH values of buffer solutions containing glucose (278 mmol/l) and/or blood (10%) were measured with both electrodes to see if there were any observable differences between them.
As a result, the pH values given by AT and GL matched each other in the range of 4.0<pH<6.9. Although AT tended to give lower readings than GL under alkaline conditions (6.9< pH<9.2), a linear relationship between the two was observed. Therefore, AT readings lower than 6.9 were directly interpreted as actual pHs, while AT readings higher than 6.9 were processed according to the regression line to extrapolate actual pHs. Based on this interpretation, neither glucose nor blood affected AT to deviate from GL. Thus, the use of this AT as a pH measuring device is encouraged.

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Failure of guided tissue regeneration (GTR) therapy is often caused by incomplete or poorstabilization of the barrier membrane. Therefore, we conducted experiments to improve the adaptaion and stabilization ability of the poly (lactic acid-coglycolic acid) (PLGA) membrane by applying polylactic acid elastomers (Gum seal glue) to the interface of the barrier membrane collar portion and tooth surface.
This study was designed to evaluate the effect of the Gum seal glue-enforced PLGA membrane on class III furcation involvement treatment (when GTR therapy was used). Experimental periodontitis was induced bilaterally on the lower third and fourth premolars of three mongrel dogs. Flap surgery was performed on all of the defects before the membrane was put in place. In the control site, only a PLGA membrane was applied and in the experimental site, a Gum seal glue-enforced PLGA membrane was used.
Eight weeks postoperatively, the dogs were sacrificed and non-decalcified sections were prepared for histological evaluation.
The results were as follows:
1) When compared to the height of the original defect, the linear distance of new bone was higher in the experimental site than the control site (48.04±27.83% vs 23.17±12.00%).
2) The linear distance of new cementum was higher in the experimental site than the control site (86.64±15.14% vs 67.95±14.64%).
3) When compared to the original defect, the area of new bone was markedly higher in the experimental site than the control site (34.17±21.63% vs 14.25±12.19%).
4) The mean length from the gingival margin to the top of the furcation fornix was 0.06±0.06 mm in the experimental site and 1.36±2.10 mm in the control site.
From these results, we can conclude that the Gum seal method was effective in improving the adaptation and stabilization of the PLGA membrane when it was used in GTR therapy.

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Hard oxidized water (HOW), pH 2.0-3.0, containing 10-50 ppm chlorine and which has been shown to exert strong bactericidal effects within a short time, has been investigated in terms of its usefulness for controlling plaque formation. However, HOW has been associated with the problems of deterioration of metallic restorations and the demineralization of in situ teeth. The purpose of this study was to determine the bactericidal effects of soft oxidized water (SOW), pH 5.0-5.5 at chlorine concentrations ranging from 50 to 80 ppm on microorganisms in vitro . Twelve strains of 12 species of microorganisms, including 1 strain of Bacillus subtilis, were cultured in broth until the late logarithmic phase and centrifuged to obtain samples in tubes. After the samples had been cultured with SOW or HOW for 10 sec to 10 min, sodium thiosulfate was added to the tubes to stop the effect of each type of oxidized water. Samples were spread over the surfaces of agar plates and incubated aerobically for 48 hours at 37... Bactericidal effects were evaluated in terms of whether or not colonies formed on the agars.
HOW displayed no effect on B. subtilis, but SOW displayed bactericidal effects on all microorganisms tested.
The results show that SOW has a stronger bactericidal effect than HOW.

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The present study was carried out to compare the plaque removal effect of conventional interdental brushes (made of stainless steel wire ; the main element, Fe) and newly developed interdental brushes (newly developed wire; the main element, Co). Both interdental brushes were relegated to 0.25 mm and 0.30 mm wire-diameter groups, by monitoring interdental brushing pressure (20, 30 and 40 g), the effectiveness in removing artificial plaque from the proximal surfaces of model teeth was determined.
We found that both wire-diameter groups, in which the newly developed interdental brushes were used, showed more effective plaque reduction at all brushing pressures and that plaque removal ratios were significantly increased. Furthermore, by altering brushing pressure, plaque removal ratios of the newly developed interdental brushes were fixed as compared with conventional interdental brushes. These observations suggest that the newly developed interdental brushes remove plaque from proximal surfaces more effectively than conventional interdental brushes.

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Oral condition concerning caries, periodontal disease and removable dentures of all adult inhabitants of Enoshima and Hirashima, two of the small islands in Nagasaki Prefecture without a dentist, was investigated by conducting oral examinations in 1990. Guidance regarding the oral condition, dental treatment and instruction in plaque control were given to the group of inhabitants and to individuals in 1990-1992. In 1993, oral conditions were reexamined. 60% of inhabitants who needed dental treatments received treatment on a doctor's advice. The changes in oral condition over the three year period were analyzed by individual follow-up. Each inhabitant had been observed for major changes in oral condition for three years. A tendency for dental caries to decrease and for prostheses to improve was seen though periodontal disease worsened. The reasons are that 70% of inhabitants already had moderate and deep periodontal pockets (CPITN≥3) in 1990, and successful periodontal treatment requires that a series of treatments be performed several times, as compared with treatment of dental caries or prostheses placement. These results indicate that more than motivation of inhabitants is needed. Prophylactic treatments, such as scaling at regular intervals for inhabitants with gingivitis and dental calculi (CPITN≥2), are essential to prevent the progression of periodontal disease on islands which have no dentist.

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There are few reports describing the role of the secretory immune system against periodontopathic bacteria in periodontal disease. The purpose of this study was to examine the role of salivary IgA antibody against periodontopathic bacteria. Peripheral blood and unstimulated saliva were collected from the 25 adult periodontitis patients and 10 healthy volunteers. Total IgA antibody, total secretory IgA antibody, and IgA antibody specific for periodontopathic bacteria were measured using enzyme-linked immunosorbent assay. Salivary total IgA antibody levels in patients were significantly higher than those in healthy subjects (p<0.01). There was no difference between healthy subjects and periodontitis patients regarding the salivary IgA antibodies specific for P. gingivalis, A. actinomycetemcomitans and F. nucleatum. Patients were divided into two groups according to the amount of IgA antibody specific for periodontopathic bacteria. If the amount of IgA antibody against a bacterial species exceeded the mean plus 2 SD of the healthy subjects, the patients were classified as H-group, while the other patients were classified as L-group. As to the IgA antibody specific for P. gingivalis, H group patients has significantly low numbers of teeth showing. ≥3mm, ≥5mm, and. ≥7 mm pocket depths (p<0.05). The numbers of teeth showing. ≥25%, ≥50%, ≥75% bone loss were lower in H group than L group, but the difference was not statistically significant. These results suggest that salivary IgA antibody specific for periodontopathic bacteria is not always produced in adult periodontitis patients, and that salivary IgA antibody specific for P. gingivalis might have a protective role in periodontitis.

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The aim of the present investigation was to determine the clinical and microbiological effects of long-term undisturbed plaque formation on the gingiva and peri-implant mucosa. Four mongrel dogs were used in the study. Their mandibular premolars on both sides were extracted. Three months later, four Brånemark® implants (BR, n=8) or Integral® implants (IN, n=8) were placed in the edentulous area of each dog. After 3 months, abutment connection was performed, and plaque control was maintained for 30 days until a superstructure was formed. Then the plaque control was terminated to allow gross plaque accumulation. Clinical, radiographical and microbiological data were recorded at the baseline, and 3 and 6 months after the termination of plaque control.
Values for the clinical indices, which included probing depth, plaque index and bleeding on probing, were increased at 3 months on both implant and tooth sites, and remained unchanged at 6 months. Significantly more implant sites showed bleeding on probing than did tooth sites. Neither implants nor tooth sites showed clinically significant changes in mobility. At 3 and 6 months, bone resorption was not observed by radiography. In microscopic morphological observation, cocci dominated with baseline proportions of 64% on BR, 86% on IN and 83% on teeth, then decreased by 6 months to 38%, 54% and 52% respectively. The proportion of motile bacteria increased from 4% to 19% on BR, 0.8% to 15% on IN and 1.5% to 14% on teeth. In a culture study, black-pigmented anaerobic rods, which consisted predominantly of Porphyromonas gingivalis-like bacteria, increased from 11% to 17% on IN, 11% to 28% on BR, and 7% to 23% on teeth. No Actinobacillus actinomycetemcomitans-like organisms were isolated. These results indicate that peri-implant tissue may be more susceptible to plaque accumlation than periodontal tissue, and that teeth may serve as a reservoir for the bacterial colonization of implant sulcus.

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We determined self-recognition levels of the severity of periodontal disease by questionnaire in patients and screened patients for actual periodontal status by using the CPITN code classification. Screening was performed in one dental office on 494 first-visit patients aged between 34 and 62 years (males: 426; females: 68; mean age: 47.9 years). Their severity recognition levels for their own disease status were proportional to the CPITN code numbers. Nevertheless, the severity of disease and need for treatment recognized by the patients differed from our recommended periodontal treatment, i. e., oral hygiene instruction, scaling and root planing, and maintenance phase therapy. These results suggest that motivation and consultation are the most important factors for patients to become aware of their actual periodontal disease status.

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'ISODINE ® Gargle' is a mouth rinse for antimicrobial agents that is composed of Povidene iodine. We evaluated the effectiveness of 'ISONINE ® Gargle' mouth rinse using clinical parameters and subgingival plaque over a 2 week period. Twenty patients, diagnosed as having adult periodontitis without systemic problems, were selected. Ten patients in the experimental group, were instructed in Bass methods and used the mouth rinse at 4 times a day. Another group performed brushing only without the rinse, under the same conditions. Clinical diagnosis and bacterial counting based on morphological classification, were recorded initials, and at 1 and 2 weeks.
There were significant decreases in the Plaque Index and Gingival Index in the experimental group, whereas the control group showed a significant decrease only in the Plaque Index. As for microflora during the experimental period, in comparing the 2 groups, the mouth rinse group showed a significant decrease in motile rods as compared to the control group. This finding suggests that oral rinsing with 'ISODINE ® Gargle' is effective for daily use.

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