This study was carried out to examine the relationship and the changes of the occlusal force with the masseter activity after the periodontal therapy.
Study 1. Twenty persons with healthy periodontal tissue and normal dentition and 20 patients with periodontitis were selected. Their occlusal force and masseter activity were determined using the Dental Prescale® and Muscle Balance Monitor BM-II® and the relationship between occlusal force and masseter was examined. Study 2. Seventeen patients with periodontitis underwent periodontal tissue examination; occlusal force and masseter activity were determined and the relationship between then was examined before and after tooth brushing instruction, scaling and root planing.
The results of study 1 showed a significant positive correlation between the masseter activity, the occlusal area and the occlusal force in both healthy subjects and patients with periodontitis. The results of study 2 showed a significant increase in the occlusal area, the occlusal force and the masseter activity as inflammation of the periodontal tissue improved after periodontal therapy. However the mean occlusal pressure and the maximum occlusal pressure decreased slightly. There was a significant positive correlation between the masseter activity, the occlusal area and the occlusal force before and after periodontal therapy.
Thus, the results suggest that the condition of periodontal tissue is related to the occlusal force and masseter activity, and that occlusal force and the masseter activity improve as the condition of the periodontal tissue improves in response to periodontal therapy.

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The goal of current periodontal therapy is to provide connective tissue adhesion on root surfaces that have lost their attachment to the peridontal membrane. An important consideration is the adhesive capacity of periodontal ligament fibroblasts on the root surface.
This study investigated the mechanism of cellular adhesion to root surfaces after periodontal therapy, and the influence of treating root surfaces that have been exposed to surface collagen. Additionally we investigated how the presence of the ligand-binding site (RGD arrangement) of the adhesive molecule integrins influenced the morphology of cell adhesion and the expression of integrins. Human periodontal ligament fibroblasts (HPLF) were cultured onto citric acid-treated or untreated dentin specimens, glass plates, and collagen-coated glass plates. The expression of the integrin β₁ subunit (integrin β₁) in cell-substrate focal adhesions was examined using an immunohistochemical transmission electron microscope and a confocal laser scanning microscope.
Furthermore, integrin β₁ gene at cell surfaces was analyzed by RT-PCR (reverse transcriptase polymerase chain reaction).
The results showed that root mineralization is useful in promoting cell adhesion onto root surfaces. Integrin β₁ was mainly involved in cell adhesion in the RGDS (-) medium. Conversely, although integrin β₁ was expressed on the cell surfaces in the RGDS (+) medium, it was minimally involved in cell-substrate adhesion mediated by the formation of focal adhesions.
These findings indicate that integrin β₁ expression on focal adhesions was affected by ligands. Therefore, the nature of the root surface and/or the surrounding cellular conditions must be considered in order to obtain HPLF attachment during periodontal regeneration.

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Inducement of periodontal ligament fibroblast adhesions on to root surfaces is important in wound healing after periodontal surgery.
Root surface demineralization, Fibronectin (FN) application, or GTR are known methods for promoting these adhesions.
This study was undertaken to examine the effects of blood coagulation factor XIII, which has an action-promoting effect on FN adsorption to collagen, and on the adhesive capacity of human periodontal ligament fibroblasts (HPLF) to matrix. HPLF were inoculated onto factor XIII-coated dentin blocks and collagen-coated glass plates, and the early adhesion dynamics of the cells were serially examined. The cytoskeleton, i. e., cell morphology, and FN localization were investigated using a confocal laser scanning microscope.
The results showed that factor XIII promoted early cell adhesion both on collagen-coated glass plates and dentin blocks. However, there were no significant differences in adhesion morphology 12 hours after the start of culture.
There findings suggest that adhesion molecules rather than changes in the properties of the substrate, that is, thepresence or absence of collagen fiber exposure, may be involved in early cell adhesion to the substrate of HPLF. Thus, factor XIII is considered useful in the promotion of early adhesion of the HPLF to the root surface.

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In order to clarify the aggregation mediated by their fibrilar structures on the cell wall surfaces of plaque bacteria, human supragingival dental plaque were ultrastructurally examined.
Samples were collected from native tooth enamel upper and lower first molar) over one to (seven days after suspension of tooth cleaning. The specimens were prepared for electron microscopic observation by means of freeze-substitution method which was useful in examining the fine fibrilar and membranous structures.
The fibrilar structures of bacterial cell walls were classified into three types according to their characteristics of distribution as follows: 1) peritrichous type fibrils protruding throughout the whole circumference of bacterial cell wall surface; 2) localized type fibrils protruding from a portion of the surface; 3) mixed type fibrils protruding uncontinuously from several parts of the surface.
Abundant peritrichous type cells were recognized in most bacteria of one to three day specimens, and refleced their unique structure. Tight cell-to-cell aggregation between homogeneous and/or heterogeneous species in all these specinens was observed. However, qualitative and quantitative declines in species with fibrilar structures were observed in bacterial flora from four or five day specimens. Accompanying this decrease in fibrilar structures, fibrilar structure-mediated aggregation, especially between heterogeneous species of bacteria, remarkably diminished with the exception of aggregation between vesicles on cell walls of gram-negative bacilli and sparse peritrichous fibrils of gramnegative filamentous bacteria.
The morphological findings of bacteria in human supragingival plaque indicate that bacteria proliferating in the early stage of dental plaque formation colonize by their own fine fibrilar structures, and that the tendency of aggregation in this system decreases in old plaque.

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LPS from gram negative bacteria have been challenged to involve in the periodontal disease. Aim of this study, have observed morphological changes for polymorphonuclear leukocytes PMNs) properties when phagocytic reaction with LPS stimulating. PMNs isolated from the venous blood on healthy volunteers. PMNs treated with Escherichia coli-derived LPS (final concentrations of 0, 0.1, 1, 10, and 50 μg/ml) subsequently, treated cells incubated with goat anti-rabbit IgG antibody-coupled carboxylate beads 0, 10, 30 min for phagocytic reaction. After fixation, NBDphallacidin was added. Obtained samples were serially observed the F-actin (cytoskeleton) polymerization and to evaluate for the position of beads against PMNs intra-or extra-cells using a confocal laser scanning microscopes. The superimposed digital images have been got by a simple transmission images and fluorescent one. These results suggests, 1) F-actin appeared surrounding the beads at phagocytic process and localized within the area of the pseudopodium. 2) Number of ingested beads increased with the 0.1μg/ml LPS treatment, but it decreased with the more rich LPS stimulation. 3) Phagocytosis was delayed with the rich LPS environment and the beads on the cell surface were found not to be incorporated into the cells.

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Glycosaminoglycans (GAG) have been found in higher level in the gingival crevicular fluid associated with increased metabolic activity, such as periodontal inflammation or alveolar bone remodeling, and have also been proposed as a maker of periodontal disease activity.
There appears, however, to be some confusion about the different levels of GAG depending or the assay method used.
To compare three assay methods for GAG and glycosaminoglycan-linked proteoglycans (GAGPG) in biological samples, we analyzed three samples: from gingival homogenate supernatant, synovial fluid, and carrageenin-induced exdate.
The isolated GAG were separated by electrophoresis on a cellulose acetate membrane and stained with Alcian blue. Substrate-dye complex was evaluated in a scanning densitometer. Unsaturated disaccharide isomers of chondroitin sulfate, ob taineol following chondroitinase digestion from isolated GAG, were analyzed by high-performance liquid chromatography. For comparison, a small amount of GAG-PG was assayed using the enzymelinked immunosorbent assay (ELISA) method, with a combination of monoclonal antibodies and specific enzyme digestion.
Results were that the level of GAG obtained by the electrophoretic method was similar to that obtained by high-performance liquid chromatographic assay, while the GAG-PG level obtained using the ELISA method was 3-80 times higher than that by the other two methods. Dermatan sulfate was not detected by biochemical analysis in the samples from synovial fluid and carrageenin-induced exudate.
This indicates that an assay of GAG-PG dose not necessarily substitute for GAG assay by biochemical methods.
These findings may be useful in selecting the assay methods for GAG and help discuss ions of the results for biological samples by different assay methods.

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The purpose of this case report was to describe the long-term effect of subgingival mechanical irrigation, that is irrigation with mechanical debridement using ultrasonic scaler tips, in a patient with moderate to advanced periodontitis.
A 46-year-old male patient without any systemic disease, whose chief complaint was severe mobility of the right maxillary incisor, was referred to the Department of Periodontics, Kagoshima University School of Dentistry, on June 1986. Severe swelling of the gingiva and bone resorption, was observed and diagnosed as moderate to advanced adult-type periodontitis.
After initial examination, O'Leary plaque control records were maintained at less than 10% during initial treatment, and subgingival mechanical irrigation was performed vigorously using ultrasonic scaler tips on minimum power once a week for one month. Re-examination was performed to assess the healing response of the periodontal tissue after one month of irrigation treatment. Further subgingival mechanical irrigation was perfomed once a week for seven months. Follow-up evaluation was performed eight months after initial examination. Scaling and root planing using hand instruments were performed there after.
At initial examination, the mean probing pocket depth (PPD) and frequency of bleeding on probing (BOP) was 2.7mm and 82%, respectively. After one month of subgingival irrigation, the mean PPD and BOP was 2.5mm and 31% respectively. After eight months of subgingival irrigation, the mean PPD and BOP was 2.0mm and 22% respectively and marked reduction of probing pocket depth was observed. At the third examination, and after scaling and root planing, the mean PPD and BOP was 1.9mm and 9% respectively.
It was noted that the remarkable healing of periodontal tissue was observed without scaling and root planing. A'so, the findings suggest that the subgingival mechanical irrigation using ultrasonic scaler tips mey be a potential healing aid, without involving cumbersome instruments. Further study is required to assess the effects of subgingival irrigation in a clinical application.

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The purposes of this study were (1) by means of such a randomized controlled study to compare the effects of the guided tissue regeneration (GTR) procedure with conventional flap surgery (CFS) as a control treatment on the healing of deep intrabony and class II furcation defects, and (2) to determine factors affecting the clinical outcome of the GTR procedure using a multivariate approach.
Sixty deep intrabony defects and 20 class II furcation defects were treated in 80 adult periodontitis patients aged from 35 to 60 years. After completion of initial therapy, those defects were assigned to either by a GTR or CFS procedure with matching age, gender, teeth and defect morphology. A postsurgery protocol emphasizing wound stability and infection control was used. Treatment effects were evaluated at 6 months and 1 year postsurgery.
Both GTR and CFS for intrabony and furcation defects resulted in a clinically and statistically significant improvement in probing pocket depth (PPD), vertical and horizontal clinical attachm ent level (CAL-V, CAL-H), marginal tissue recession MTR) and radiographic bone loss (BL), at 6 months and 1 year postsurgery compared to baseline measurements. Moreover, there was a more favorable improvement in CAL-V, MTR and BL of the GTR group than in the CFS group at 6 months and 1 year postsurgery for intrabony defects. In addition, the GTR group showed greater improvement in CAL-H than CFS group at both 6 months and 1 year postsurgery for furcation defects. When multivariate analysis assessing the significance of the tested factors in determining the healing outcomes following GTR procedure was performed for intrabony defects, PPD at baseline was of predictive value for vertical clinical attachment gain (CAL-V gain) at 6 months postsurgery, and CAL-V gain and MTR at 6 months postsurgery were of predictive values for CAL-V gain at 1 year postsurgery. BL at baseline and at 6 months postsurgery was also of predictive value for bone fill at 6 months and 1 year postsurgery, respectively. In furcation defects, CAL-H and MTR at baseline were predictive values for horizontal clinical attachment gain (CAL-H gain) at 6 months postsurgery, and CAL-H gain at 6 months postsurgery was of predictive value for CAL-H gain at 1 year postsurgery.
These findings suggest that initial PPD and BL in intrabony defects, and initial CAL-H in class II furcation defects might be useful in assessing the regenerative potential of a given site and the degree could be predictive values for a follow-up in tissue of improvement as early as 6 months postsurgery regeneration.

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