The purpose of this study was to determine the effects of anti-Bacteroides gingivalis (Bg) and anti-Actinobacillus actinomycetemcomitans (Aa) antibodies on Bg and Aa respectively.
Bg and Aa were resistant to complement-mediated bactericidal activity, and killing by PMN. However a significant reduction in CFU of Bg and Aa was found when these bacteria were incubated with the antibodies and not agitated.
This would suggest that the antibody was capable of aggregating or phagocytizing, but not killing, these bacteria when complement and PMN were added. Moreover the antibodies had no effect on bacterial proliferation.
Anti Aa antibody also had no effects on killing of Aa or PMN infiltration in experimentally established periodontal pockets in dogs.

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The microbial flora from 46 adult periodontitis lesions of 23 patients and 18 sites in 9 healthy persons were examined and levels of serum IgG antibody to gram negative periodontal disease-associated bacteria were measured by enzyme-linked immunosorbent assay. Plaque samples and serum samples were tak en 40-50 days after initial preparation consisting of scaling and root planing. To evaluate the effects of the therapy on 10 patients with adult periodontitis, changes in clinical parameters were compared with alterations of the microbial flora and serum IgG antibody levels.
Black-pigmented Bacteroides species, mainly Bacteroides gingivalis, were found to be predominant in periodontitis lesions. A significant relationship was found between the prevalence of B. gingivalis and elevated titers of serum IgG antibody against the microorganism. No relationships between Bacteroides intermedius, Actinobacillus actinomycetemcomitans and elevated titers of serum IgG antibody to them were detected. The fact that there was no marked reduction of serum IgG antibody to B. gingivalis after initial preparation suggests that a more extended, longitudinal study is required. Although brushing resulted in a significant reduction of the number of total cultivable organisms in samples from periodontal pockets, no significant proportional changes in gram-negative bacteria in the lesional flora were found. Initial preparation was not effective in eliminating gram-negative bacteria from deep periodontal pockets. However, the microbiological shifts, especially the reduction in the proportion and frequency of detection of B. gingivalis in periodontal pockets, was paralleled by significant improvement in the clinical parameters.

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The effect of initial preparation in adult periodontitis was evaluated by changes in clinical parameters and immunofluorescence microscopic counts of periodontal disease associated bacteria.
Subgingival plaque samples were taken with sterilized paper points from 10 sites of 5 periodontally healthy persons and 44 sites of 23 adult periodontitis patients. Twenty-one diseased sites were periodically examined after plaque control and scaling, root planing. The direct immunofluorescence technique was used to detect Bacteroides gingivalis, Eikenella corrodens, Fusobacterium nucleatum and Treponema denticola, Bacteroides intermedius, Actinobacillus actinomycetemcomitans, Bacteroides forsythus and Wolinella recta were counted by the indirect immunofluorescence technique.
The proportions of B. gingivalis, B. forsythus, F. nucleatum, E. corrodens, T. denticola and W. recta in periodontitis lesions were significantly higher than those in healthy sites. The proportions of B. gingivalis and T. denticola were significantly related to GI, PlI, BI and PD, those of B. forsythus and W. recta to GI, PlI and BI, E. corrodens to GI and PH, and F. nucleatum to BI. Reduced proportions of T. denticola were found in samples taken after establishment of proper plaque control. Subgingival scaling and root planing resulted in the reduction of proportions of B. gingivalis, E. corrodens, T. denticola and B. forsythus in the samples. The samples from positive bleeding sites contained higher proportions of B. gingivalis, T. denticola, B. forsythus and W. recta than did resolved sites.
The present study shows that the immunofluorescence technique which detects B. gingivalis, T. denticola and B. forsythus is useful in monitoring the efficacy of initial preparation.

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The activity of peptidases in periodontal pockets of patients were examined by using four different synthetic enzyme substrates, and surveyed their correlation with the microbial populations of subgingival plaque and clinical symptoms. The substrates were (1) α-N-benzoyl-DL-arginine-β-naphthylamide (BANA), (2) N-carbobenzcxy-glycylglycyl-arginine-4-methoxy-β-naphthylamide, (3) α-N-benzoyl-L-arginylglycyl-L-phenylalanyl-L-proline-4-methoxy-β-naphthylamide and (4) N-carbobenzoxy-prolyl-L-alanylglycyl-L-proline-4-methoxy-β-naphthylamide.
Whereas substrates (1) and (2) were hydrolyzed more specifically by peptidases of mainly Bacteroides gingivalis and Treponema denticola, substrates (3) and (4) were susceptible to most of the strains of black-pigmented Bacteroides, Capnocytophaga and T. denticola. Correlation between the peptidase activity and the level of Spirochetes in the plaques were observed with the substrates (1), (2) and (3). Substrate (3) had the strongest correlation also with the level of the black-pigmented Bacteroides and with the depth of the periodontal pockets, suggesting that it is a better substrate for enzymatic diagnosis than BANA which is currently used as an indicator of oral Spirochetes and the black-pigmented Bacteroides.

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The role of the periodontal ligament in periodontal tissue regeneration was evaluated. The materials included bilateral upper 1 st premolars and lower 2 nd, 3 rd, and 4 th premolars of 11 adult Beagle dogs, aged from 3 to 6 years. Before implantation, the right teeth were extracted and kept for a period of more than 3 months in “a solution for reserving teeth”. The left teeth on the other hand, were extracted and soon implanted thus retaining the periodontal ligament into the newly created bone cavities prepared in the right edentulous areas. At the same time, the right reserved teeth were implanted into the left tooth sockets.
Implanted teeth were periodically observed macroscopically, radiographically, and histologically for a 6-month period. Macroscopical observation showed good clinical repair in the bilateral sides of the tooth implantation with and without a periodontal ligament.
After a 6-week experimental period, radiographic observations of the implanted lower right teeth having a periodontal ligament revealed lamina duralike findings. Histopathological investigation revealed ankylosis and root resorption on the left side, where the reserved teeth without a periodonal ligament were implanted. But regeneration of the periodontal tissue complex, which consisted of the gingiva, alveolar bone, cementum, and periodontal ligament, was generally observed in the implanted right teeth having a periodontal ligament.
These results suggest that the periodontal ligament cells play a significant role in periodontal tissue regeneration.

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The purpose of this study was to determine histochemically the characteristics of elicited multinucleated giant cells adhering artificial graft materials. As artificial graft materials, resorbable ceramic. β-tricalcium phosphate, non-soluble porous hydroxyapatite and non-soluble non-porous hydroxyapatite were examined, with devitalized bone particles serving as the control. Both test and control graft materials were implanted subcutaneously in rats and mice.
Acid phosphatase and tartrate resistant acid phosphatase were positive in elicited multinucleated giant cells adhering to both artificial graft materials and devitalized bone particles. Elicited multinucleated giant cells elicited adhering to sutures were negative. The number of multinucleated giant cells positive to non-specific esterase was minimum except in areas they adhered to sutures.
Elicited multinucleated giant cells adhering to graft materials showed enzyme activities similar to those of osteoclasts, and it was suggested that artificial graft materials may be absorbed by osteoclasts.

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The present study was performed to evaluate the effects of hydroxylapatite (HAP) on tissue regeneration in various types of furcation involvement. Upper premolar tooth sites of 9 beagle dogs (3-6 years old) were used. HAP particles were implanted into three types of furcation defects: Class III lesion (by Glickman) in 2nd premolar sites, artificially caused by intrafurcal suturing or spontaneously developed about 3 months after extraction of the 1st premolar; Class IV lesion in 4th premolar sites artificially produced 2 months before implantation; and through-and-through furcal bony defects in 3rd premolar sites at the time of HAP implantation. Macroscopic, radiographic and microscopical investigations of the postoperative status were carried out at intervals of 1, 2, 3 and 6 months.
The appearance of the gingiva in bony defect sites was almost the same as that in the presurgical status 2 weeks after implantation, although gingival inflammation was persistent in Class III and IV lesions. Most particles in Class III and IV lesions exfoliated until 2 weeks after implantation, and the junctional space between recipient bone and particles could not be distinguished, probably as a result of incorporation of HAP and osseous tissue.
Histological observation revealed that HAP particles were surrounded by new bone located at the top of the alveolar crest in all defects. However, there were no obvious signs of coronal bone formation or connective tissue attachment in Class III and IV lesions up to 3 months after the operation. At 6 months there was evidence of new bone formation over the presurgical crests in Class III and IV lesions. On the other hand, there were obvious signs of connective tissue attachment and bone formation in bony defect sites, probably induced by the tissue of the periodontal ligament remaining after the surgical procedure, and nonphysiological ankylosis between root and bone was frequently observed. There were notable findings, such as newly formed osteoid tissue intervening with the adhesive particles, calcified tissue intervening between HAP particles and root surface showing ankylosis, and peripheral osteoid formation in the HAP particles.
It is postulated that HAP has no apparent role in induction of bone formation, although there is chemical affinity to calcified tissue, and it is effective in yieldi-ng a volume of bone-like tissue where osseous repair could be performed. However, HAP did not enhance regeneration of lost periodontal structures including connective tissue attachment.

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Serial changes in the microvascular pattern beneath the inner epithelium and in the periodontal connective tissue attachment on the upper incisors in adult mongrel dogs, were studied by scanning electron microscopy to elucidate the process of reconstructing the vascular architecture following mucoperiosteal flap surgery. In the early stage of wound healing, capillaries beneath the epithelium in the marginal gingiva were transformed into glomeruli, in the course of the predominantly elongation type of angiogenesis. At the junctions, newly formed sinusoidal vessels were formed in the course of predominantly sprouting type of angiogenesis, and anastomosed with vasculatures between the flap and the periodontal membraine. In these newly formed vessels, vascular glomeruli in the marginal gingiva and newly formed sinusoidal vessels at the coronal side of the junctions were transformed into a capillary network beneath the inner epithelium accompanying the epithelization. At the apical side of the junctions, newly formed sinusoidal vessels showed a series of changes to cope with alterations of the tissue environment accompanying connective tissue attachment, but the vasculatures established after surgery showed a dense and irregular arrangement compared with the control side. These results show that the attachment mechanism obtained by wound healing differ from the original one.

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The purpose of this study was to evaluate a new system of drug delivery to periodontal pocket by means of intracanal dressing and additional iontophoresis in vitro. Forty extracted human teeth with a single root were used. After the root canal was prepared endodontically, the periphery root apex was painted with the Silux system (3 M Co.) to close the apical foramen. Each tooth was planted into an agar block.
Three drugs (zinc iodide-iodine, penicillin G. potassium, minocycline HCl) were used (Table 1), and 50μl of each drug was injected into an individual root canal. Then a cathodic current (3 mA×40 min) was applied using an automatic current volte regulater (PAV-200, Jooko Co.) with a platinum wire electrode inserted in the root canal (Fig. 1).
The degree of drugs diffusion in the agar around teeth was estimated by individual color reactions zinc iodide-iodin test for starch, penicillin G. potassium test for phosphomolybdic acid, minocycline HCl test for ferric chloride).
And also, the effects of root planing and etching by Quick Jet (Yosida Co.) on the root surface were evaluated in the same way.
The results were as follow:
1. The degree of diffusion by intracanal electrical medication was greater in the cervical third area than the middle and apical third.
2. Several small areas stained by the iodo-starch color reaction were observed around the cervical root surface where greater diffusion was observed.
3. Many dentinal tubules were observed on a limited root surface where root planing and Quick Jet, were employed caused greater diffusion.
4. The results suggest the new delivery system for management of the microorganisms by intracanal medication and additional iontophoresis.

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This study was performed to evaluate the efficacy of digital subtraction radiography in detecting alveolar bone changes. In order to test the sensitivity of quantitative evaluation by subtraction radiography, a copper equivalent thickness obtained from digitized radiographs was compared with the actual mineral content of bone phantoms with 15 different minerals and 25 bone specimens. Results demonstrated that the copper equivalent thickness correlated well with the actual mineral content (bone phantoms:γ_s=1.0, bone specimens:γ_s=0.985). In order to test the ability of digitized subtraction radiography in assessing alveolar bone changes in vivo, subtraction images were compared with histological features. The experimental angular bony defects were treated with conservative periodontal therapy in 3 monkeys. The standardized radiographs were taken longitudinally after therapy, and subtraction images were made from the sequentially obtained radiographs. In addition, for fluorescent histomorphometrical evaluations of new bone formations, the animals were dosed with oxytetracycline, calsein solution and arizarin complex solution. Radiographic and histological evaluations were scheduled to provide healing periods of 2, 3, 4, 5, 6 and 9 weeks after periodontal therapy. Subtraction radiography offered an objective method to follow histological changes of alveolar bone, and the copper equivalent thickness obtained from subtraction radiographs correlated with the histometric bone volume (γ_s=0.9023, p<0.01). The results of these studies indicated that subtraction radiography was useful in monitoring alveolar bone changes associated with periodontal disease and treatment and that the quanitative measurement of periodontal bone changes by subtraction radiography was feasible.

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The purpose of this study was to investigate whether plaque bacteria invade exposed radicular dentin after root planing or chemical root treatment in vitro. Pieces of dentin were cut out from impacted third molars. The surface of all dentin pieces was treated with sandpaper at 240) so as to make the surface roughness of dentin pieces equal to that of the root surface after root planing (RP surface). Half of the dentin pieces were treated with citric acid (pH 1.0) for 3 minutes (CA surface). After sterilization, each dentin piece was incubated at 37°C in a culture medium inoculated with either S. mutans or S. sanguis. After 1, 3, 7 and 28 days of incubation, the invasion of microorganisms into the dentinal tubules was histologically examined using a light microscope.
The following results were obtained.
1. The invasion of S. mutans and S. sanguis into the dentinal tubules was observed at 1, 3, 7 and 28 days. The depth and number of bacterial invasion into the dentinal tubules were positively correlated with incubation time on CA surfaces but not with RP surfaces.
2. The depth and the number of bacterial invasion into the dentinal tubules were higher on the CA surfaces than the RP surfaces.
3. Since the citric acid treatment of scaled and root planed root surfaces may accelerate bacterial invasion from treated root surfaces, the use of citric acid might be harmful in patients with inadequate plaque control.

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This study examined the phagocytic activity of rat peritoneal resident macrophages to determine the movement of macrophages in local inflammation in periodontal disease. We studied phagocytic activity by enzymelinked immunosorbent assay (ELISA) and used the peroxidase-anti-peroxidase soluble complex PAP; soluble immune complex) as a marker in.
We also determined the basic conditions of this examination and studied the effects of bacterial components and the supernatants of sonicated periodontopathic bacterias.
We obtained the number of applied macrophages, the concentration of PAP to use and the incubation time. The phagocytic activity of macrophages was enhanced significantly by the bacterial components lipopolysaccharide (LPS) and muramyldipeptide MDP).
Phagocytic activity was also enhanced by the addition of the supernatant of sonicated Bacteroides gingivalis at 40μg/ml (concentration of protein) and significantly suppressed at 320μg/ml. Moreover, activity was significantly enhanced by the supernatant of sonicated Capnocytophaga suputigena at 40μg/ml and 160μg/ml, and suppressed by the supernatant of Fusobacterium nucleatum at a low concentration of protein (5μg/ml).
These results suggested that LPS of gram-negative bacteria's endotoxicity and MDP on pivotal structure of peptidoglycans, which are bacterial cell surface components, exerted an effect on phagocytic activity. It was further indicated that the phagocytic activity of macrophages varied with the effects of each periodontopathic bacteria.

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Sex hormones are closely related to the onset and progression of periodontal disease.
The purpose of this study was to evaluate the effects of sex hormones on the metabolism of human periodontal ligament cells.
Human periodontal ligament cells and gingival fibroblasts were prepared from 7 donors with normal gingiva. 17β-estradiol and progesterone were purchased from Sigma Chemical Company.
The effects of sex hormones on cell morphology, alkaline phosphatase activity, cell proliferation, DNA synthesis, collagen synthesis and non-collagenous protein synthesis were investigated. The results were as follows;
1. Periodontal ligament cells showed osteoinductive-like cells in the cell morphology and alkaline phosphatase activity.
2. DNA synthesis was stimulated by 17β-estradiol and progesterone in the presence of 5% fetal calf serum.
3. Collagen synthesis was inhibited by 17β-estradiol and progesterone, while non-collagenous protein systhesis was inhibited by 17β-estradiol and low concentrations of progesterone.
4. The addition of serum into culture medium was necessary to induce the basic metabolism of human periodontal ligament cells.
It was demonstrated that sex hormones are closely related to the metabolism of human periodontal ligament cells.

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We studied the effect of periodontal treatment scaling, SC; root planing, RP; scaling follo (wed by citric acid, SC+CA; and root planing followed by citric acid, RP+CA) of periodontally diseased root surfaces on the initial attachment of human gingival fibroblasts in vitro. Root slices were prepared from surgically extracted human normal and periodontally involved teeth. Each treated root slice was placed in a well of a 24-well plate containing a PBS-antibiotic solution (penicillin, 200units/ml; streptomycin, 200μg/ml) for 1 hr. at 4°C Then, to each well was added 1×10⁴ cells in 1ml of α-MEM, and the plates were incubated for 24 hr. After the root slices were fixed and stained, the morphological changes and the numbers of attached cells were determined under a dissecting microscope.
The fibroblasts on the controls (untreated normal roots) and the RP-roots appeared spindle-shaped with a few cell processes. The cells on the SC-roots were rounded or slightly elongated. The cells on the roots treated with citric acid (SC+ CA and RP +CA) had were flat and seemed well attached to the surface. The number of cells attached on RPand RP+CA-roots was increased to the control level, but those on SC-and SC+CA-roots were showed about 60% of the control. No significant differences in the numhers of cells were found between RP and RP+ CA treatment or between SC and SC+ CA treatment.
Our observations suggest that root planing, whether or not citric acid is used, enhances the initial cell attachment on root surfaces, but citric acid application has no effect. However, citric acid treatment may be considered to have an additional affect in promoting adherence and growth of fibroblasts.

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The effects of nicotinate ethyl ester treatment on the gingival blood circulation of plaque induced inflammation in monkeys were determined.
The blood flow, amount of hemoglobin and oxyhemoglobin rate (oxyhemoglobin/total hemoglobin) in gingival blood circulation in addition to bacterial colony forming units (CFU), gingival index (GI), probing depth (PD), loss of attachment (LA) and amount of gingival crevicular fluid (GCF) were used as parameters.
Besides 1% nicotinate ethyl ester paste (nicotinate paste), 0.5% chlorhexidine (CHX) paste as an antibacterial agent, a mixture of the two pastes and the base alone as a control were used.
1. The blood flow, amount of hemoglobin, CFU, GCF, PD and GI increased as inflammationdeveloped, and these showed significant correlations.
2. The oxyhemoglobin rate showed no corresponding change with inflammation.
3. Nicotinate paste, CHX paste and the mixed paste seemed to reduce the inflammation of the gingiva as assessed by the blood flow, hemoglobin amount, CFU and GCF amount compared with the control paste.

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In vitro studies with osteoblast-like cells, revealed that in addition to preventing the immediate outflow and promoting stabilization of implant materials, these cells have the additional effect of promoting the mending and early calcification by coating the materials with collagen. The materials used for the experiment were minute hydroxyapatite, betatricalcium phosphate and bovine sintered bone. To these, atelocollagen which is solble in pepsin extracted from calf corium and crosslinked by using ultraviolet rays was added.
We observed the cells very closely after these materials were added to alpha-modified eagle's medium containing 10 mM beta-glycero phosphate, 10% fetal bovine serum and osteoblast-like cells and the cultures incubated at 37.. and 5% CO₂. After 14 and 21 days, cells were fixed and stained with Alizarin Red S and Von Kossa stains to measure calcification. As a result of the collagen coating, positive areas appeared and, compared to the control improvement of the early mending was apparent.
The results suggest that by coating the materials with collagen, the osteoblast-like cells show better mending and early calcification.

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Physical, chemical, biological and implant tests on calcium phosphate prepared by the mechanochemical method with wet milling were performed to determine their applicability for periodontal therapy.
1. Materials synthesized by the new method had a stoichiometric ratio of Ca/P=1.50 and a density of 3.70g/cm³ and coincided with the standard pattern of β-TCP (ASTM Card) very well.
2. The surface structure of dense type sintered at 1, 100.. showed fewer fine pores than the dense type sintered at 1, 050...
The surface structure of the porous type sintered at 1, 050.. showed finer pores, except for a continuous large pore than the porous type sintered at 1, 000.. .
3. Specific conductivity tests should higher solubilities of the porous type than of the dense type in pure water, and of materials sintered at low temperature than at high temperature.
4. Cytotoxicity studies with V-79 cells showed no significant differences from the controls, and other biological tests revealed no abnormalities.
5. At three and six weeks after implantation in muscles, all of β-TCP was enclosed with collagen fiber. The porous type of β-TCP was almost completely fused to cranical bone in rabbits three weeks after implantation. The dense type of β-TCP was completely fused to cranical bone six weeks after implantation.
From these results, it can be concluded that β-TCP prepared by the new method is of high purity and biocompatibility. Consequently β-TCP is expected to be effective in clinical use.

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It has been unclear whether M. T. M. is acceptable for patients treated with bone grafts using hydroxyapatite (HAP), which is not biodegradable. Therefore we studied histological changes in bone among HAP during orthodontic tooth movement. HAP was implanted into artificial bone defects adjacent to second premolars in beagle dogs, and as a control no material was implanted Three months after implantation, the second premolars were moved with orthodontic force. Then they were observed histopathologically. The results obtained were as follows.
The amount of movement of the teeth in implanted sites was less than in the controls. In the pressure zone, resorption of bone by osteoclasts was observed in both the implanted and the control sites, in addition, root resorption occurred adjacent to HAP. Furthermore mutinucleated giant cells were closely attached to HAP and were surrounded by bone and connective tissue. In retention period there was ankylosis between the roots and bone around HAP. In the tension zone, additional bone from HAP was observed. Bone defects were filled with bone in the implanted sites, but with connective tissue in the controls.
These results suggest that bone among HAP was resolved by osteoclasts. Clinically, HAP implantation for the pressure zone should be avoided becau se of the occurrence of root resorption and ankylosis. because HAP implantation produces more repaired But for the tension zone it seems to be effective bone.

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Ultrasonic imaging equipment has been applied to periodontal diagnosis, but the standardization of this examination remains difficult.
We found that a multiple reflected echo appeared on ultrasonography when the periodontal probe was inserted in the periodontal pocket. The purpose of this study was to investigate this multiple reflected echo as a reference point for ultrasonography and to measure the distances between the periodontal probe and alveolar crest in pigs by using ultrasonography.
The multiple reflected echo disappeared under the following conditions : 1) when the change in horizontal position was more than 0.7mm, 2) when the change in horizontal angle was more than 5 degrees, and 3) when the change in vertical angle was more than 20 degrees. The results in pig specimens showed that the difference in the distance from the top of the periodontal probe to the alveolar crest was less than 0.2 mm on ultrasonic and direct histological measurements.
It was concluded that the multiple reflected echo of the periodontal probe can be used to standardize ultrasonographic examination.

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The purpose of this study was to investigate the accuracy and reproduction of a microelectrode with a glass capillary, and to discuss the, correlation between the pH level and the microflora in periodontal pockets or the clinical findings in the various stages of periodontal disease.
The upper or lower anterior teeth of 34 patients with mild to severe periodontal disease were examined. Before the measurement, supragingival plaque was removed from each tooth. A special glass capillary was incorporated in the microelectrode to cover its tip, so that it would not touch the pocket walls or tooth surfaces during pH measurement. After the pH in the crevicular fluid was determined, subgingival plaque was collected with paper points from each periodontal pocket. This bacterial plaque was sonicated with saline solution, and examined under a phase contrast microscope with a calibrated eyepiece graticule to count and morphotype groupings of microorganisms as 1) coccoid forms, 2) rods, 3) filaments, 4) motile rods, 5) spirochetes or other cell types. Crevicular fluid flow measurements and clinical findings (pocket depth, and gingival inflammation) were also investigated. The following conclusions were drawn:
The electrode with capillary was useful to determine the pH of the crevicular fluid clinically. A reduction in pH level was seen in deep pockets or severe gingival inflammation. A close correlation was seen between salivary and crevicular pH. The pH level was significantly positively related with the proportion of coccoid forms, but was negatively correlated with the proportion of motile organisms that are reported to be related with periodontal disease.

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The purpose of the present study was to evaluate the effectiveness of granular hydroxyapatite as an alloplastic bone implant material in infrabony periodontal defects.
Thirty-five infrabony defects in 28 subjects with marginal periodontitis were used. The patients were instructed in oral hygiene and received several sessions of scaling and root planing. Granular hydroxyapatite was implanted into test sites with infrabony defects following application of internally beveled full thickness flaps, root planing, and defect debrideent. Pocket depth and attachment level were recorded before and 3 and 6 months after surgery . Gingival recession, mobility of the tooth, plaque index, and gingival index were also recorded before and 1 and 2 weeks, and 1, 3 and 6 months after surgery.
Redness and swelling of the gingiva and increase in tooth mobility appeared transiently after surgery, however, they disappeared in a short time. A significant reduction of mean pocket depth of 3.4mm and a significant increase in the mean attachment level of 2.5mm were observed at 6 months after surgery. The mean gingival recession during the experimental period was only 0.9mm. The amount of hydroxyapatite remaining implanted in the infrabony defect was 73% 6 months after surgery.
The data and clinical impression suggest that hydroxyapatite has a potential as an alloplastic implant with clinically apparent acceptance by soft and hard tissue.

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Topical chemotherapy of periodontal disease using several drug delivery systems (DDS) is currently being attempted. PT-01 is a DDS which consists of fast- and sustained- release parts containing ofloxacin as an antibacterial agent. Since PT-01 was found to sustain the antibacterial effect for 7 days in a periodontal pocket, it was used for periodontal patients without root planing or scaling in this study. PT-01 and a placebo were applied to two separate and opposite pockets of 46 patients, once a week from the first visit (week 0) to week 3. The clinical parameters (plaque index, gingival index, tooth mobility, bleeding on probing, pus discharge, and probing depth) were evaluated from weeks 0 to 4. At the end of the test (week 4), global improvement at the two sites was assessed. The clinical parameters and the global improvement of the PT-01 and placebo-treated sites were compared statistically.
All parameters at the PT-01 sites except for tooth mobility showed much greater improvement than at the placebo sites. The global improvement of PT-01 sites was also significantly greater than that of the placebo sites. No side effects could be seen in patients treated with PT-01. These results indicate that topical chemotherapy using PT-01 could be effective and safe for periodontal therapy.

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In 8 patients with periodontal diseases under good supragingival plaque control, 22 test teeth each having a pocket not more than 4 mm deep were treated respectively with 3 consecutive administrations of tetracycline immobilized cross-linked collagen film (TC film) at intervals of 1 week, with onceroot planing and with both of these. The therapeutic effects were compared both clinically and micro biologically.
The results revealed improvements in clinical symptoms such as reduction in the depth of the pocket, bleeding on pocket probing and the like for each treatmet group in 6-12 weeks.
The second and third groups also showed remarked gingival recession.
Further more, the density of intrapocket microorganisms showed a remarked decrease up to the 8th week for each treatment group and the population of spirochetes showed a decrease up to the 6th week for the first treatment group and up to the 8th-12th week for the second and third treatment group.
The results show that both local application of the TC film and root planing are effective in periodontal treatment, but not the combined treatment.

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Two molars having furcation grade II involvements were selected from each of six patients with periodontal diseases. One molar received a local application of tetracycline immobilized cross-liked collagen film four times at one-week intervals (TC filmtreated group) and the other received no treatment (non-treated group). The clinical and microbiological effects were, as follows,
1. Throughout the experimental period, no significant differences in pocket depth, attachment level, bleeding on pocket probing, periotron unit, gingival index and plaque index were noted between the TC film-treated group and the non-treated group.
2. One week after TC-film application, the treated group showed significant decreases in the density of microorganisms and the proportion of spirochetes compared with the non-treated group. The results revealed the insufficient effectiveness of the local application of TC film by itself for the treatment of teeth having furcation grade II involvements.

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Three different sites which have more than 5mm pocket were randomly selected in each periodontal patient and were divided into three groups: PT-01 treated site, placebo treated site and control site. After application of either PT-01 or placebo twice for two weeks, subgingval scaling and root planing were performed. Then PT-01 and the placebo were applied weekly to the periodontal pocket for four weeks and clinical and microbiological evaluations were made.
The results obtained were as follows:
1. On clinical evaluation, significant improvement was found in the PT-01 treated site in comparison with the placebo treated and/or control site.
2. On microbiological evaluation, slight improvement was found in the PT-01 treated site, whereas there was no significant difference among the three sites.

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Four different sites were randomly selected in each periodontal patient and divided into four group: PT-01-treated site (A), PT-01 treatment combined with scaling (S+A), placebo-treated site (P) and placebo treatment combined with scaling (S+P). PT-01 and the placebo were applied to the periodontal pocket weekly on days 0 to 28, and clinical and microbiological evaluations were made.
The results obtained were as follows:
1. Weekly changes in plaque index, pus discharge and mobility of the tooth were not observed in any group.
2. In gingival index, bleeding on probing, pocket depth and gingival crevicular fluid, significant improvement was found in A in comparison with P and in S+A in comparison with S+P.
3. In total number of subgingival bacteria and in the ratio of motile rods and spirochetes to the total number of bacteria, significant reduction was found in A in comparison with P and in S+A in comparison with S+P.

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We developed a new tchnique insted of usual retrograde apicoectomy for cases in which apical lesions appear after prosthetic treatment.
The technique is as follows. After treatment of the apical area by raising a flap, part of the labial bone is removed and the labial surface of the root is exposed. Then the labial part of the root is removed and the root canal is opened. After that, the residual carious dentin is removed completely. At the final stage, the open root canal is filled with tooth adhesive and low viscosity composite resin (Clearfil-SC ®). This technique is indicated for cases in which the crown restoration is not removed for some reasons and treatment from apical side is not possible. This technique is clearly the last choice, but many teeth will remain.

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The purpose of this study was to evaluate the efficacy of porous hydroxyapatite (HAP) as an implant material into human periodontal defects. Thirty three patients affected by marginal periodontitis were studied. Following initial therapy, 44 periodontal osseous defects received grafts of HAP granules and blocks during flap surgery. Radiographic and various clinical examinations were performed before surgery and 1 and 2 weeks, and 1, 2, 3, 6 and more than 6 months after surgery.
The results were as follows:
1. Postsurgical inflammation of the gingiva disappeared in a short time. Further more open wounds and discharges of HAP disappeared in the first month. There were no clinical problems in the sites receiving HAP implantation.
2. Radiographic demarcation lines between the implanted HAP and the surrounding alveolar bone bacame unclear at the beginning of bone repair.
3. At six months after surgery, the mean values of gingival recession, decrease in pocket depth and clinical attachment gain were respectively 0.9mm, 2.7mm, 1.9mm. Additional observation beyond 6 months showed an attachment gain of 2.0mm.
4. The attachment gain was less in the cases of one wall osseous defect and of furcation involvement in lower molars.
These results suggest that HAP implantation is clinically effective, howerver, careful application is needed for the cases of one wall osseous defect or furcation involvement.

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In this clinical study we evaluated the use of hydroxyapatite ceramic (HAP) implant in conjunction with the surgical treatment of periodontal osseous defects. Fifty-five defects in 23 patients were treated and filled with HAP particles (BDHAP-101). At 6 months and 12 months after the placement of particles, the sites were evaluated by gingival margin heights, periodontal pocket depths, attachment levels, tooth mobility, the gingival index (GI), and radiographic analyses. Oral hygiene status was estimated by the plaque index (PlI). There were significant improvements with regard to probe depth, attachment level, tooth mobility, and GI. The radiographic anlysis showed a similar density of the adjacent bone and the particles, suggesting excellent biocompatibility. There were no changes in PlI before or after the placement of implants.

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