The association of heparan sulfate proteoglycan (HSPG) with osteoclasts has not been clearly established. We have studied the immunohistochemical localization of HSPG using a specific monoclonal antibody against HSPG in osteoclast-rich tissues. Periodontal tissues from beagle dogs in which periodontitis had been induced with silk ligature and radii from newborn rabbits were used. Tissue samples were embedded in paraffin and sectioned. Immunoperoxydase staining of sections was performed using an anti-HS monoclonal antibody (HepSS-1) and biotin streptavidin. These sections were also stained for tartrate-resistant acid phosphatase (TRAP) to localize osteoclasts. In periodontal tissues, bone resorbing TRAP-positive multinucleated cells as well as TRAP-positive mononuclear cells located close to alveolar bone showed HSPG-positive cytoplasmic staining. In rabbit radii, the cytoplasm of TRAP-positive mononuclear and multinucleated, as well as, TRAP-negative cells stained positive. Whereas, sections pretreated with heparitinase as a control did not stain. In addition, isolated rabbit osteoclasts were cultured in medium-199 for 48 hours at 37... Immunocytochemical studies using HepSS-1 was performed for cultured osteoclasts. Laser confocal microscopic observation showed HSPG-positive staining located in the cytoplasm of osteoclasts. These observations indicate that HSPG is associated with the osteoclastic cell lineage. J. Jpn. Soc. Periodontol., 41: 229-237, 1999.

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The present study was designed to evaluate the potential for reformation of bone and cementum in newly formed tissues under ePTFE membranes. Thirty-two teeth of 16 mongrel dogs were studied. The premolars, except for the mesial root of the mandibular third premolars (P 3 M), were extracted. Following crown resection, root canals of P 3 M were filled. Following the elevation of soft tissue flaps, circumferential alveolar bone was removed to the 5 mm root level, and the exposed root surfaces were carefully planed to remove the cementum 3 months after the extraction. Before the flaps were repositioned and sutured, membranes were placed over the root surfaces in the experimental group. The membrane was adjusted to cover the root surface from the root-crown level to approximately 1 mm apical to the bone. No membranes were placed before the flap repositioning in the control group. The membrane was removed 4 weeks after healing, and the root with soft tissues grown under ePTFE membrane (tissue with membrane) was extracted and implanted into bone cavities prepared in edentulous areas of the mandibular jaws. The root with tissue in the absence of the membrane (tissue without membrane) was implanted as the control. The implantation was scheduled to allow observation at 4, 8 and 16 weeks. Then the animals were sacrificed, and the histological sections were prepared. New bone and cementum failed to form on the bone and root surfaces located in contact with the tissue without membrane. In areas of the alveolar bones and roots where the tissue with membrane was preserved for transplantation, new bone and cementum formations occurred between the bone and the adjacent tissue with membrane, and the root and the adjacent tissue with membrane. Immunoreactivity to the antiosteocalcin antibody was not identified in the tissue without membrane, while the tissue with membrane showed immunoreactivity. These immunohistochemical findings suggest that the newly formed tissues beneath the ePTFE membrane possess the ability to form new bone and cementum. J. Jpn. Soc. Periodontol., 41: 238-251, 1999

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The inflammatory cytokines play an important role in the pathogenesis of periodontal diseases. In this study, the mRNA expression of cytokines and inducible nitric oxide synthase (iNOS) in inflamed gingival tissue was analyzed using reverse transcription-polymerase chain reaction (RT-PCR). The presence of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in periodontal lesions was also evaluated.
In patients with periodontitis, the expression of interleukin (IL) -6 and iNOS mRNAs in periodontal lesions was significantly higher than of healthy individuals. IL-6 mRNA expression was also significantly higher at the sites with positive bleeding on probing (BOP), than at BOP negative sites. The mRNA levels of IL-1 α and IL-8 at sites with A. actinomycetemcomitans infection were significantly higher than those at the sites without A. actinomycetemcomitans infection. On the contrary, the levels of IL-10 were significantly lower than those at A. actinomycetemcomitans negative sites. However, the samples from the sites infected with P. gingivalis did not reveal higher levels of cytokine mRNAs compared with those from the sites without P. gingivalis infection.
These results indicate that the expression of IL-6 may be an indicator of the inflammation in gingival tissue. Furthermore, the expression of iNOS mRNA in periodontal lesions was confirmed. It is suggested that iNOS may be involved in the inflammatory process in periodontitis. The presence of different periodontopathic bacteria may affect the cytokine expression in inflamed gingival tissue. J. Jpn. Soc. Periodontol., 41: 252-263, 1999.

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Local irradiation of the superficial layer of periodontal tissue using a CO₂ laser has received much attention as a means of forming a site where periodontal tissue may be regenerated. In this study, we examined the feasibility of using a CO₂ laser to treat the surface of the dental root. Morphological changes in the irradiated surface of dentin and the depth of irradiation to the dentin were examined using scanning electron microscopy (SEM) and confocal laser scanning microscopy. To examine the regeneration of periodontal tissue after CO₂ laser irradiation, experimentally induced periodontitis in dogs was irradiated with CO₂ laser treatments. The newly adhered and regenerated bone tissue was then examined histopathologically. The following results were obtained: 1) The amount of smear layers removed from the surface of the dentin and the increase in the degree of jaw opening were dependent on the energy density (0.6J/cm² 0J/cm²) of the laser. When the energy density was 1.2 J/cm² more, the intertubular dentin resolidfed. 2) The depth of irradiation to the surface of the dentin increased when the energy density of the laser was increased. 3) An energy density of 1.0J/cm² was found to be the most suitable level for dental root treatments. 4) A significant amount of regeneration, i. e., new adhesion and new bone growth, was observed in periodontitis cases that received postoperative laser irradiation treatments with an energy density of 1.0J/cm², as compared with cases that did not receive iradiation treatments. J. Japan. Soc. Periodont., 41: 264-276, 1999.

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Clinical evaluation was performed on 6 teeth in 18 generally healthy subjects. They were divided into the following 3 groups: healthy subjects, healthy sites and active sites of gingivitis. A total of 108 dental crevices or periodontal pocket samples were analyzed microbiologically.
The total number of cultivable bacteria, the number of black-pigmented anaerobic rods (BPRs), and the percentage of BPRs to the total number of bacteria in the active gingivitis sites (31 sites) were significantly higher (p<0.05) than in those of the healthy subjects (36 sites) and in those of the healthy sites of gingivitis (41 sites). The percentage of Prevotella intermedia to the total number of BPRs in the healthy and active sites of gingivitis were 38.1 and 34.2%, respectively, and were higher than in the healthy subjects (7.1%). However, the percentage of Prevotella nigrescens to the total number of BPRs in the healthy and active sites of gingivitis were 18.6 and 24.3%, respectively, and were lower than in the healthy subjects (40.9%). The percentage Porphyromonas gingivalis to the total BPRs in the healthy and active sites of gingivitis were 0.2 and 5.2%, respectively, and this bacterium was not found in the healthy subjects. The numbers of P. intermedia, P. nigrescens and P. gingivalis were the highest in the active site of gingivitis, and were higher in the healthy sites of gingivitis than in the healthy subjects.
Consequently, BPRs, especially, P. intermedia and P. gingivalis seemed to be the putative pathogens of gingivitis. These putative pathogens might be transmitted from the active to the healthy sites in gingivitis, because the numbers of P. intermedia and P. gingivalis in the healthy sites of the gingivitis were also higher than in the healthy subjects. J. Jpn. Soc. Periodontol., 41: 277-286, 1999.

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In recent years, various studies have been reported indicating that mental stress is one of the risk factors for the onset of periodontal disease. These studies suggested that when mental stress exerts pressure on a person, an increase in the concentration of serum glucocorticoid and/or a decrease in NK cell activity occurs. The purpose of this present study was to investigate the influence of glucocorticoid and lipopolysaccharide (LPS) from periodontal pathogenetic bacteria on bone resorption in vitro. Mouse bone marrow cells were used as the source of osteoclastic cells. The number of emerging TRAP positive MNC obtained by stimulation with dexamethasone (Dex), a synthetic glucocorticoid, and/or with LPS as a control were measured. The quantity of Interleukin-1 beta (IL-1. β) released into the culture fluid of marrow cells treated with the agents either singly or in combination was also measured, with an ELISA kit.
The results on the comparison of the number of emerging TRAP positive MNC among Dex-treated, LPS-treated, and combined treatment cultures revealed. The number of TRAP positive MNC were increased by the combination of LPS and Dex. IL-1. β production was stimulated by LPS alone, but not by LPS and Dex or Dex alone. These results suggest that, Dex stimulate osteoclast-like cell formation, and mental stress will be a factor of alveolar bone loss. J. Jpn. Soc. Periodontal., 41: 287-294, 1999.

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Some highly filler-filled resin composite materials have been developed as new hybrid restorative and prosthetic materials: These materials have good physical and mechanical properties and color revivability and have been used clinically. However, the periodontopathology of bacterial adhesion to the surface of these materials is still unknown. The purpose of the present study was to evaluate the difference in adhesion of Porphyromonas gingivalis (P. gingivalis) to these hybrid materials in GAM medium. Three different types of hybrid materials (Estenia®, Artglass®and Conquest™) were examined and a self-cured acrylic resin (RTPR) and a 20 sm gold alloy cast the controls. P. gingivalis was used in the bacterial adhesive examination and the human-monocyte cell line THP-1 was used for the cytotoxic test. Each material surface was polished according to clinically established procedures. Then the surface roughness value (Ra) for each material was measured. The results of the roughness tests showed that the 20 k gold alloy and all the hybrid materials had much smoother surfaces than the RTPR material. Adhered P. gingivalis increased with the increase in the roughness of the material's surface. Cell cytotoxity was not observed Do you mean “was not observed in any... ” Then say “None of the exgeriencnbal or control materials showed cell cytotox” the experimental or control materials. These results suggest that hybrid materials could have less bacterial adhesion in GAM medium. The hybrid materials tested may be acceptable materials for clinical dentistry, and can maintain healthy periodontal tissue. J. Jpn. Soc. Periodontal., 41: 295-301, 1999.

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Three volatile sulfur compounds (VSC) including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide in mouth air were estimated by gas chromatography in 194 subjects complaining of halitosis. Mouth air odor, tongue dorsum odor, and nose air odor were also estimated by organoleptic methods. The relations between oral malodor and clinical parameters (the amounts of tongue coating, probing depth, gingival index, and plaque index) were also examined. There were significant correlations between each VSC level and each organoleptic odor score. The correlation of nose odor score to each VSC level was lower than that of mouth odor score or tongue odor score. In the multiple regression models, only methyl mercaptan had a significant independent effect on mouth air odor and tongue dorsum odor. There were significant correlations between each VSC level and each clinical parameter. In the multiple regression analysis, tongue coating and gingival index showed a significant independent effect on hydrogen sulfide; tongue coating, probing depth, and gingival index showed asignificant independent effect on methyl mercaptan ; and probing depth and tongue coating showed a significant independent effect on dimethyl sulfide. All clinical parameters showed independent effecton the mouth odor score. The effect of tongue coating was greater than that of gingival index, probing depth, and plaque index. These results show that the measurement of VSC is useful in estimation of oral malodor, and that the relationship of tongue coating and periodontal disease to oral malodor can be demonstrated. J. Jpn. Soc. Periodontol., 41: 302-312, 1999.

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The purpose of this study was to examine repair of connective tissue attachment after mechanical injury. The buccal junctional epithelium and dentogingival fiber from the lower first molars of rats were mechanically removed. The animals were killed after 1, 3, 5, 7, 10, 15, 20, 30 and 60 days, and paraffin serial sections were prepared from their mandibles. The sections were stained with H. E. staining for histopathological observation of repair of periodontal tissue. Immunohistological staining of proliferating cell nuclear antigen (PCNA) was performed to observe the number of proliferatingcells. The procedure of periodontal wound healing was divided into two phases, namely, the phase of hard-tissue resorption from 1 to 10 days, and the phase of periodontal repair from 15 to 30 days. The ratios of PCNA-positive cells to whole cells in the periodontal ligament peaked twice on day 3 or 5, and on day 15. On the other hand, the ratios in periostium showed only a peak on day 3 or 5. These results suggest that cells in the periodontal ligament are involved in not only periodontal repair but also hard-tissue resorption. J. Jpn. Soc. Periodontol., 41: 313-320, 1999.

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The purpose of this study was to evaluate the effects of absorbable collagen membrane (BioMend™) on treatment of infrabony defects and class II furcation defects. Fifty-five systemically healthy patients were treated by guided tissue-regeneration (GTR) technique using a type I bovine collagen membrane (Bio Mend™). Clinical measurements including probing depth (PD), gingival recession (GR), clinical attachment level (CAL) and mobility were obtained on the day of surgery and 3 and 6 months postsurgery . Radiographs were taken on the day of surgery and 6 months postsurgery and radiographic bone loss was calculated. The results of this study indicate that at 3 and 6 months postsurgery a significant decrease of PD (3.0mm and 3.2mm) and increase of CAL (2.5mm and 2.7mm) had occurred compared to the presurgery status. GR at 3 and 6 months postsurgery was 0.6mm. Bone loss improved significantly (7.9%). Membrane exposures were noted in 9 cases at 1 week, 6 cases at 2 weeks and 3 cases at 4 weeks after surgery. No foreign body reaction was observed during this study. This study suggests that use of absorbable type I bovine collagen membrane (Bio Mend™) may have beneficial effects for the GTR technique. J. Jpn. Soc. Periodontol., 41: 321-330, 1999.

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The aim of the present investigation was to evaluate the effect of the supragingival plaque-control period combined with self-control and professional tooth cleaning in clinical improvement after initial preparation including scaling and root planing. Thirty-six patients with adult periodontitis were selected and were divided into 4 groups according to the supragingival plaque control period (1, 2, 3 and 6-months). Clinical parameters including plaque-control record, probing depth, probing attachment level and bleeding on probing after initial preparation were compared between the 4 groups. Plaque-control record improved before scaling and root planing and maintained a satisfactory level after initial preparation. At sites with 3-5mm pockets before treatment, significant pocket reduction appeared after 3 and 6 months, and this reduction was greater than that at 1 and 2 months. The percentage of sites with probing attachment gain was significantly different in each group (45.1% of 2-month group, and 62.1% of 3-month group). When bleeding on probing after initial preparation was compared, there was no significant values in each group. Thus, results suggest that setting a period of supragingival plaque-control for more than 3 months is important for improvement after initial preparation by scaling and root planing. J. Jpn. Soc. Periodontol., 41: 331-338, 1999.

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The acid conditioning effects of minocycline on the root surface with mechanical root cleaning were investigated in this study. Root surface specimens were randomly assigned to scaling group (control), polishing group (polish), superficial debridement group (SL) and deep debridement group (DL) with minocycline solution (10mg/ml). The antimicrobial activities of minocycline solution (10mg/ml, 10min) against P. gingivalis, by moniforing penetration rate and attachment rate were evaluated.
The results showed that all groups possessed antimicrobial activity against P. gingivalis on days 0 and 7 after root conditioning with minocycline solution (10mg/ml, 10 min). Especially, DL group exhibited significantly higher antimicrobial activity (Day 0: average 94.8 unit [p<0.01], Day 7: average 54.1 unit [p<0.05]). The penetration rate to root surfaces were significantly higher in the DL group (42.7. μm) and in the SL group (21.5. μm) (p<0.01). In the attachment rate, the SL 92.8% and DL groups 97.2% were significantly higher than other groups (p<0.01).
These results suggest that minocycline root conditioning will be expected on the cementum surfaces. J. Jpn. Soc. Periodontol., 41: 339-346, 1999.

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