The aim of this study is undertaken to process of periodontal tissue regeneration and the metabolic activity of osteoblasts after implantation of hydroxyapatite (HAP) and tricalcium phosphate (TCP) granules.
Bone defects were artificially prepared in the alveolar septa of the bilateral upper first molars and second molars of Wistar rats. After the HAP and TCP granules were implanted into the defective sites on the left side, and the gingival flaps were closed. At the defective sites on the right side, as controls, the gingival flaps were closed without implantation. The rats were sacrificed 1, 3, 5, 7 and 14 weeks after implantation, and excised tissue sections were observed both pathologically and by autoradiography using ³H-proline. The results obtained were as follows.
1. Pathological findings
1) 3 weeks after HAP implantation, HAP granules were present in fibrous connective tissuse, and some of them were directly bound to the matrices of regenerated bone. Observation 5 weeks after implantation revealed HAP granules embedded in the regenerated bone matrices and foreign body giant cell reaction at the margin of the granules located in connective tissues. HAP granules were directly bound to the regenerated bone matrices without intermediary fibrous tissues 7 and 14 weeks after implantation. Connective tissues showed high-grade regeneration of collagen fiber bundles, which arrangement tended to be fixed in the mesial snd distal direction.
2) 1 week after TCP implantation, inflammatory cellular infiltration of the gingival connecive tissues around TCP granules was relatively mild, together with macrophages adhering to the margin of some granules.
Some TCP granules were directly bound to the matrices of regenerated bone, 3 weeks after implantation, some granules also showed vertical binding of collagen fiber bundles. There were many foreign body giant cells at the margin of the granules. 5weeks after implantation, the regenerated bone matrices showed growth in the coronal direction, embedding TCP granules with stable regeneration of collagen fiber bundles of the gingival connective tissues. 7 and 14 weeks after implantation, relatively large TCP granules were found to be replaced by regenerated bone matrices, showing high-grade regeneration of collagen fiber bundles.
2. Autoradiographical finndings
1) HAP granules implantation group
There was no uptake of ³H-proline into the regenerated bone matrices or the gingival connective tissues around HAP granules, while the uptake of ³H-proline into the entire area around the root apex and the vicinity of the alveolar septum was observed with time (weeks) after HAP implantation.
2) TCP granule implantation group
Although the time (weeks) -course of ³H-proline uptake into the entire area around the root apex and the vicinity of the alveolar septum could be observed after implantation, there was no uptake of ³H-proline into the regenerated bone matrices or the gingival connective tissues around HAP granules.
These results suggest that HAP and TCP provide nuclei for bone rgeneration through thieir inclusion in newly generated periodontal bone tissues, although it is difficult to produce definite induction of bone tissues by HAP or TCP alone. It is also apparent that both types of granule are useful bone implantation materials for restoration of the physiological morphology of alveolar bone in periodontal surgical treatment.

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In order to investigate the relation between the masseter muscle reflex (especially the periodontalmasseteric reflex) and sensations evoked by electrical stimulation of periodontal tissues, the present study was peformed on 5 males (aged 24. 34 years) with normal dentitions. Recordings of electromyograms were made from the right masseter muscle with bipolar surface electrodes. Electrical stimuli (1 msec duration square-wave, 1/1 sec) were applied to the upper right cental incisor and its gingiva. The anode side of the stimululating electrode was bonded to the facial side of the crown of the tooth, the cathode was placed in contact with the gingiva. In some experiments the tapping of the teeth when then came into occlusion triggered the electrical stimuli after either delay of 50 msec, 300 msec or 600 msec, these stimuli corresponded with the clench, open or close phases of the cycle respectvely.
1) During clenching, electrical stimulation caused two excitatory reflex responses (an early response-ER, latency: about 8 msec, a late response-LR, latency: 50. 100 msec) and a silent period (SP, lateny: about18msec).
2) The threshold of the ER coincided with that of sensation, and the incidence of ER was 47. 100% (average 77%) at this stimulus intensity. On the other hand, the threshold of SP also coincided with that of sensation, but the incidence of SP (13.47%, average 24%) was lower than that of ER at this intensity.
3) After the infiltration of anesthesia (2% Xyolcain) in the electrical stimulating region, perception and jaw reflex (ER, LR, SP) elicited by the electrical stimulation had completely vanished.
4) The effect on the reflex (ER, SP) of changing the occlusal force levels while maintaining a consta-nt stimulus intensity was studied. At 0 kg, no response could be detected. The amplitude of ER was markedly increased with increasing force, while the duration of the SP was slighly decreased with increasing force.
5) When the electrical stimulation was applied in each phase during open-close-clench cycles, ER was recognized in the occlusal and closing phases.
However, electrical stimulation caused no response in the opening phase. Because ER elicited by the electrical stimulation to the periodontal tissues had a short latency (about 8 msec), and ER was completely absent after anesthesia to the stimulating region, it is suggested that ER may account for the monosynaptic excitation by the“periodontal-massetericreflex” that passes through the mesencephalic nucleus. The threshold ofthe ER coincided with that of sensation, and the incidence of ER was higher than that of SP at the same stimulus intensity. These findings suggest that the“periodontal-massetericreflex” may regulate the occlusal force during mastication.

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The effect of infection with Eikenella corrodens 1073-R (Ec) on the progression of ligature induced periodontitis was examined in Wistar rats. The cervix of the second maxillary molar of rats was ligated, and a single dose of 75mg/kg body weight cyclophosphamide (Cy) was given to the half of the rats. Rats were then inoculated with 3.5×10⁸ cells of live Ec twice daily on Day 3 and 4. Rats were sacrificed on Day 1, 3, 5, 8, 11 and 18.
The number of total cultivable bacterial cells and Ec recovered from the ligated rats was higher than that from the non-ligated rats. Although the number of total cultivable bacterial cells from the ligated rats was not changed by the implantation of Ec, alveolar bone resorption of the ligated rats was enhanced by the implantation of Ec. Cy significantly reduced the number of white blood cells, and suppressed inflammatory cellular infiltrates in gingival tissue and repair of periodontal tissue. Cy enhanced alveolar bone destruction. Osteoclasts adjacent to the alveolar bone crest were found to be much more in the Cy-treated and Ec-infected rats (shown as Cy (+). EEC (+) rats) than in Cy (+). EEc (-) rats or Cy (-). EEc (+) rats on Day 5. Alveolar bone loss was also greater in Cy (+). EEc (+) rats than in Cy (+). E Ec (-) rats or Cy (-). EEc (+) rats. Without ligation, administration of Cy and infection with Ec did not induce periodontal destruction.
These results suggested that Ec caused osteoclastic bone resorption and suppression of the host defenses greatly facilitated bone destruction.

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The purpose of this study was to determine the contents (mg/dl) of secretory IgA, serum-type IgA and albumin in saliva, each secretion rates (μg/min) of secretory IgA, serum-type IgA and albumin, and the contents (mg/dl) of immunoglobulins (IgG, IgA, IgM) and complement (C3) in serum of 13 patients with periodontal disease and compare those with 17 subjects with healthy periodontal tissue in order to clarify clinically a possible mechanism involved in the inception and progression of periodontal disease. Furthermore, the correlations between clinical findings and quantitative values were examined.
The contents (mg/dl) of secretory IgA, serum-type IgA and albumin in saliva were measured by electroimmuno-assay, each secretion rates (μg/min) of secretory IgA, serum-type IgA and albumin was calculated from each content (mg/dl) and the salivary flow rate (ml/min). The contents (mg/dl) of immunoglobulins (IgG, IgA, IgM) and complement (C3) in serum were measured by single radial immunodiffusion.
The results obtained were as follow:
1. The periodontal disease group showed significantly higher PlI and GI than the healthy group, and a significant positive correlation between PlI and GI was found in the two groups.
2. In the periodontal disease group, PI showed a significant positive correlation with PD, but showed no significant correlations with PlI and GI.
3. No significant difference in the salivary flow rate (ml/min) between the two groups was found, and no significant correlations between the salivary flow rate (ml/min) and clinical findings were also found.
4. Significant negative correlations between each content (mg/dl) of secretory IgA, serum-type IgA and albumin in saliva and the salivary flow rate (ml/ min) were found.
5. The contents (mg/dl) and the secretion rates (μg/min) of serum-type IgA and albumin in the periodontal disease group were significant higher than those of the healthy group, and they showed significant positive correlations with PlI and GI.
6. The content (mg/dl) and the secretion rate (μg/min) of secretory IgA were no significant differences between the two groups and they showed no significant correlations with clinical findings in the periodontal disease group, whereas a significant negative correlation between the secretion rate (μg/min) of secretory IgA and GI was found in the healthy group.
7. The contents (mg/dl) of immunoglobulins (IgG, IgA, IgM) and complement (C3) in serum were no significant differences between the two groups and they showed no significant correlations with clinical findings in the two groups except that a significant positive correlation between the content (mg/dl) of complement (C3) and GI was found in the healthy group.
In conclusion, it was highly suggested that the direct and indirect, via the immune response, damaging effects due to dental plaque might be involved in the pathogenesis of periodontal disease, although there were particularly no obvious relationship between local and systemic humoral immune capacities of specific resistance factors and periodontal disease.

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This study was to evaluate the changes in occlusa contact area induced with occlusal interference at working side in lateral excursion. The changes in Occlusal Comtact Area (OCA), Luminosity Grade 1 (LG1..) and Occlusal Contact Position were measurec by Image analyzer system. The subjects were ten patients with occlusal interference in the latera excursion. OCA and LG1.. in the individual teeth were investigated on differences between at the left and the right side.
The results were as follows:
1. In the normal subjects, the most cases werc shown that the cuspid has continuously contacted at working side during the lateral excursion.
2. In the subjects with occlusal interference, the most cases were that the cuspid and molars showed all continuous or irregular contact.
3. In the subjects with occlusal interference, the changes of OCA and LG1.. in the individual teeth on lateral excursion were larger than in the normal subjects.
4. In the subjects with occlusal interference, the changes in OCA and LG1.. at the left or the right side were larger than in the normal subjects.

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The purpose of this study was to compare the results of free gingival grafts on the periosteal bed and the denuded bone bed.
Twenty-one mongrel dogs were used in this study. The areas of the free gingival grafts on the periosteal bed and the denuded bone bed were adjacent to each other, and the grafts were of tissue from the same dog. Both pathological and clinical comparative investigations were conducted. The results were as follows:
1. The clinical investigation revealed that up to the end of the second postoperative week there was redness and swelling in the gingival area around the graft.
2. The area of the surface of the entire graft contracted 63% during the first postoperative week and 55% during the second week. Also the denuded bone bed showed a somewhat greater tendency towards contraction than the periosteal bed.
3. The pathological findings revealed that up to the end of the second postoperative week, although the denuded bone bed showed a somewhat greater degree of inflammation, there was actually no marked difference between the periosteal bed and the denuded bone bed in this respect.
4. Three weeks postoperatively the degree of resorption on the surface of alveolar bone revealed a clear difference, with the resorption on the alveolar bone on the denuded bone side being quite noticeable.
5. Six weeks postoperatively except for the difference in the alignment of the collagen fibers there were no real differences and healing had occurred. Three months postoperatively the healing was complete with no differences at all between the two.

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Fibronectin isolated from human plasma by affinity chromatography on gelatin-Sepharose 4B was demonstrated to inhibit seeded crystal growth of hydroxyapatite in the metastable calcium phosphate solution. It was also demonstrated that the inhibition was brought about direct adhesion to hydroxyapatite crystals in addition with binding to calcium ion. The adhesion to the crystals by fibronectin was predicted to be formed by repeating dissociation and fusion. Stated reversely, these results indicate that the fibronectin in salivary secretion play a role as materials in the early stages of formation of acquired enamel pellicle.

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The effect of fibronectin (FN) on bacterial aggregation and adsorption to hydroxyapatite (HAp) was investigated to clarify the mechanisms whereby acquired pellicle and dental plaque were precipitated on the tooth surface. The FN prepared from human blood plasma amplified aggregation of bacteria which had been derived from dental plaque and cultured under aerobic and anaerobic states. The peaks of the aggregation were at the FN concentration of 3×2³ μg/ml for the aerobic sample and at the FN concentration of 3×2² μg/ml for the anaerobic sample. The adsorption of the bacteria to synthesized HAp The adsorption of the bacteria to synthesized HAp was also amplified under the presence of FN. The peaks of the adsorption were at the FN concentration of 3×2³ μg/ml for aerobic sample and at the FN concentration of 3×2² μg/ml for anaerobic sample. The present data suggest that FN may play a role in precipitation of acquired pellicle and dental plaque like many other salivary proteins do.

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The purpose of this study was to examine the effect of fibronectin application on root surface collagen fibers exposed by citric acid. Following scaling and root plaing of extracted human periodontally involved teeth, the crown was cut and removed and the root thus obtained was split longitudinally for use as samples. The samples were treated with citric acid (pH 1.0) for 3 minutes, immersed in phosphate buffered saline (PBS) containing antibiotics for 24 hours, and then treated for 10 minutes with human plasma fibronectin (PFN) in four different concentrations, that is, 0.25, 0.5, 1.0, and 2.0mg/ml. The samples not immersed in PFN but treated only with citric acid were employed as controls. The morphology of the root surface following these treatments was observed by scanning electron microscopy.
The foregoing treated root samples were cultured with use of human gingival fibroblasts and following fixation, the number of cells attached to the root surface was counted under a light microscope. A morphological observation of the attached fibroblasts was also made. The following results were obtained.
1. Some difference in the root surfaces of the controls was observed depending on the site, but many exposed collagen fibers were observed.
2. Exposure of collagen fibers was also observed on the root surface treated with citric acid plus PFN, but the fiber diameter tended to be large.
3. Though no significant difference in the number of attached cells could be demonstrated between the root surface treated with 0.25mg/ml PFN and that of the controls, a significant increase in the number was observed when treated with PFN with a concentration greater than 0.5mg/ml. Furthermore, the number of attached cells did not differ within the PFN concentration range of from 0.5mg/ml to 2.0 mg/ml. These findings suggest that citric acid treatment following root planing and treatment with PFN having a concentration greater than 0.5mg/ml are effective in enhancing attachment of fibroblasts.
4. It was observed by scanning electron microscopy following culture after either treatment with citric acid or treatment with citric acid plus PFN that the fibroblasts were so extended and densely attached that they almost completely covered the root surface.

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Peripheral blood lymphocyte subsets of 14 patients with severe progressive periodontitis aged 16 to 27 yr, and of 10 normal individuals aged 21 to 22 yr, were analyzed by flow cytometry.
The percentages (meal±SD) of fluorescent lymphocytes expressing monoclonal antibodies OKT-3, OKT-4, OKT-8 and anti-Leu-16 were as follows: 59.48±9.85%, 35.05±8.49%, 25.57±6.68% and 19.13±6.97%, respectively, in patients and 74.50±9.85%, 45.65±6.00, 30.70±5.51% and 6.07±2.31%, respectively, in normal individuals. Statistical analysis showed that the percentages of OKT-3-positive lymphocytes and OKT-4-positive lymphocytes were significantly lower in patients than in normal subjects while the percentage of Leu-16-positive lymphocytes was significantly increased in patients in comparison with normal individuals. There was no significant difference in the ratios of helper/inducer T (OKT-4) to suppressor/cytotoxic T (OKT-8) between patients and normal subjects.
The serum IgG level in patients was significantly higher than that in normal subjects (P<0.01), and the levels of serum IgM and IgA in patients were also higher than in normal subjects but without a statistically significant difference.
These results suggest that the immunological response of patients with severe progressive periodonti- tis might be different from that of normal subjects.

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Polyamine contents of gingival tissues from thirteen patients of marginal periodontitis were examined. According to clinical estimations after the initial preparation, gingival tissues were divided into two groups, inflammatory and normal gingiva. Polyamine extracted from the tissues were dansylated and separated by silica gel thin-layer chromatography.
Putrescine content in the inflammatory gingiva was 0.80±0.14 nmol/mg protein, which was about twice that in the normal gingiva. No significant differences in the contents of spermidine and spermine were observed between inflammatory and normal tissues.
These findings suggest that putrescine is related to the regulation of inflammatory process and recovery in periodontal disease.

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There are many reports on clinical parameters which reflect periodontal disease status.
The purpose of this investigation was to detect enzyme activity in gingival crevicular fluid and to clarify which enzyme parameters could shown corelatively the progressive variations of periodontal disease by recurrent acute episodes.
For this study, 4 Macaca irus monkeys were used, showing various stages of periodontitis after 3 months experimental periods without plaque control. Alkaline phosphatase, β-Glucuronidase, Acid phosphatase, IgG and total protein levels were determined in gingival crevicular fluid samples, which collected by the irrigation technique from periodontal pockets.
In results, Alkaline phosphatase varied these levels, depending on the extent of gingival inflammation, and these levels significantly increased which associated with initial stage disease activity, while Acid phosphatase had no relation to disease activities.
β-Glucuronidase levels have been evaluated for their use as possible indicators of destructive disease activity in severe periodontal disease status, on which these enzyme responses might express the resorption of alveolar bone.

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There have been several reports on mediators of enhancement of the chemotactic activity of mononuclear phagocytes. We looked for a mediator in alveolar bone by incubating the bone in RPMI 1640 medium with and without a stimulant, and studied the effect on the chemotactic activity of macrophages.
Fragments of alveoral bone were taken under sterile conditions from 8 week-old male Sprague-Dawley rats. Peritoneal macrophages were collected by introperitoneal injection of 1% sodium chloride solution. Esterase activity and viability of the induced cells was more than 85% and 98% respectively. Rat alveolar bone supernatant (Bone-sup) was prepared by taking out the alveolar bone and incubating it in RPMI 1640 medium at 37°C, in 5% CO₂ in air. During incubation, the stimulants parathyroid hormone (PTH) or sonicated Bacteroides gingivalis 381 (BG), or no stimulant were added. The effect of Bone-sup on chemotactic activity of macrophages was determined by the membrane filter method of bioassay in a multi-well chamber. In all experiments, N-formyl-Lmethionyl-L-leucyl-L-phenylalanine was used as a positive control.
Chemotactic activity of macrophages was enhanced by Bone-sup with or without a stimulant. The peak of chemotactic activity was reached in 96 hr of incubation.
Factors from rat alveolar bone or fragments of bone accelerated the chemotactic activity of macrophages, suggesting that the factor affects the function of macrophages.

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We have estimated in vitro assay system to know the precise effects of artifical bone implant materials. In this study, we isolated osteoblastic cells from fetal mouse calvaria using colony separation. These cells retain osteoblastic functions, namely the ability to produce the bone-liver-kidny-type of alkalinephosphatase and collagen and to mineralize ground substance.
To estimate the biologicalactivity and calcification of implant materials in osteoblastic cells, cells were cultured in plastic dishes contain α -MEM supplement with 10% fetal bovine serum. After 24 hr, materials put upon these cell layer, addition of 10mM β-glycero phosphate and HEPES, and 100mM sodium L-ascorbate. For the findings of 21 days cultivation, all of experiments showed the biological affinity on these cells. However the around of True Bone Ceramic (TBC) showed newly caltified evidence more than other materials.
From these results, we consider the different of surface structure, biological affinity on materials. This cell is, therefore useful for studies on the artificial dental implant materials on osteoblastic cell.

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The purpose of this study was to investigate the mode of subgingival plaque formation and its association with various microflora in the thoroughly debrided periodontal pocket by scanning electronmicroscopy. Eleven Periodontally involved teeth with an avarage pocket depth of 6 mm, were selected. Experimental surfaces were thoroughly debrided by flap operation at the baseline. Mechanical plaque control with toothbrush was maintained for 6 weeks after the operation. Then the teeth were extracted and examined by Scanning electronmicroscopy.
The following results were obtained: Subgingival plaque was formed as the continuation from supragingival plaque. No isolated plaque were recognized in the subgingival area. Average distance of formed subgingival plaque from gingival margin was 0.35 mm at bucco-proximal site, 0.67mm mid-proximally and 0.65mm lingua-proximally. The microflora of the plaque composed of coccoids and rods predominantly, but spirochetes were seldom observed. The present study suggests that supragingival plaque is intimately ralated in the formation of subgingival plaque.

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Inhibitory effects of minocycline-HCl and tetracycline-HCl on collagenolytic activities of Bacteroides gingivalis, human polymorphonuclear leucocytes (PMN) and human gingival fibroblasts (HGF) were compared.
Collagenolytic activities in the samples were determined using ¹⁴C-acetylated calf-tendon collagen as substrate. The enzymes were isolated from culture supernatant of B. gingivalis, PMN homogenate and culture media of HGF.
At the concentration of 50μg/ml in the reaction mixture, collagenolytic activity of B. gingivalis was inhibited more than 50% of the control level by both minocycline-HCl and tetracycline-HCl. Minocycline-HCl at the concentration of 100μg/ml inhibited more strongly (65%) the collagenolytic activity of PMN than tetracycline-HCl (12%) at the same concentration. On the collagenolytic activity of HGF, inhibitory effect by both antibiotics was not observed up to the concentration of 250μg/ml.
Minocycline-HCl inhibited B. gingivalis collagenolytic activity, independently of calcium ion concentration tested (5-50 mM). At the physiological calcium ion concentration (2mM), PMN collagenolytic activity was more sensitive to minocycline-HCl (70% inhibition at 50μg/ml) than HGF enzyme (20% inhibition at 500μg/ml).
These results suggest that minocycline-HCl could specifically inhibit collagenolytic enzyme which may be induced during inflammatory process, without disturbing normal collagen turn over and regeneration of gingival tissue.

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Our previous studies have been performed to establish methods for local delivery of Minocycline hydrochloride (MINO: Lederle Japan, LTD, Tokyo) in a therapy for periodontal disease.
This study was done clinically to evaluate the effectiveness, safety, and usefulness of a LS-007 medicine containing 2 percent titers of MINO. Forty five periodontitis patients (119 teeth) with periodontal pockets (≥4mm) participated in this study. The experimental systems were evaluated by comparing microbiological and clinical effectiveness of LS-007, placebo, and Minocycline tablet (Lederle Japan, LTD).
The results were as follows,
1. The effectiveness of LS-007 was examined in two delivery system ; in one system the medicine was redelivered after one week, and in the other system after two weeks. Both systems revealed similar effectiveness until after two weeks from the last delivery.
2. When LS-007 was delivered once in a week for 4 successive weeks, LS-007 demonstrated its effectiveness until after 4 weeks from the last delivery.
3. A pretreatment with scaling prior to the application of LS-007 raised the effectiveness of LS-007.
4. The systemic delivery of Minomycine tablet demonstrated microbiologically and clinically similar effect to the local delivery of LS-007. In the systemic delivery, however, there was a subject who suffered harmful side effect of the medicine.
From these results, we concluded the local delivery of LS-007 was clinically effective, safe, and useful as a therapy for periodontal disease.

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To establish a local therapy of periodontitis by using minocycline HCl, a series of studies has been conducted. The present study was to re-confirm the results of the previous investigations, and objectively evaluate the usefulness of minocycline HCl ointment, LS-007. In this double blind study the ointment base of LS-007 (PL) was used as a control. The change of bacteria in periodontal pockets after administration of LS-007 was also examined. Results are stated below.
1. The LS-007 group showed significant superiority to the PL group in clinical effectiveness, overall efficacy, usefulness, improvement rate, and usefulness rate.
2. In the improvement of clinical signs (probing depth and bleeding on probing) and in the antibacterial effect the LS-007 group showed significant superiority to the PL group.
3. The LS-007 was significantly superior to the PL in decreasing isolated bacterial species. Also, the LS-007 group showed a significant reduction in a number of isolated bacteria, number of blackpigmented Bacteroides spp., and the proportion of black-pigmented Bacteroids spp. in the total isolated bacteria.
4. Noted as side effect was subjective irritation at drug injection in one tooth each of the two groups.
From the results it was concluded that LS-007 was a useful drug for the local treatment of periodontitis.

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LS-007, containing 2% titers of minocycline hydrochloride (MINO) was applied locally to 46 patients for the treatment of periodontitis. The clinical and microbiological effectiveness, safety and usefulness of LS-007 were examined in two delivery systems: in one system LS-007 was delivered every one week (total 4 times), and in another system it was done every two weeks (total 3 times).
In the sites to which LS-007 were applied, significant improvement in gingival inflammation, probing depth, and other clinical features were observed. Furthermore, numbers of periodontopathic bacteria including Bacteroides gingivalis were also effectively eliminated in the sites. In the safty test, there was only one subject who felt uncomfortable.
In addition, antimicrobial activities of MINO and other antibiotics were evaluated by determining minimal inhibitory concentrations against those bacteria. Among the antibiotics tested, MINO revealed strong and broad antimicrobial activities against the bacterial species tested.
From these results, LS-007 was clinically and microbiologically effective, safe and useful for the treatment of periodontitis.

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Tetracycline-immobilzed cross-linked collagen film (TC film) or tetracycline-non-immobilized placebo film was localy applied four times by weekly to 33 teeth with periodontal pockets larger than 4 mm in 11 patients with periodontal diseases. The clinical and microbiological effect are summarized, as follows In the group treated with the TC film, (1) clinical indices were significantly decreased at the 4th and 7th weeks in comparison with thost at the beginging of treatment. In particular, this group showed a significant decrease in the incidence of bleeding and in gingival index as compared with the placebo group at the 4th week. (2) Total counts of bacteria in periodontal pockets showed an obvious tendency to decrease with time. The proportions of black-pigmented bacteroides and spirochetes in total bacteria were significantly decreased at the 4th and 7th weeks when compared with that at the beginning of treatment. The extent of decrease in the proportion of spirochetes at both the 4th and 7th weeks was more significant compared with placebo group.

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The purpose of the present study was to evaluate the relation between occlusal sound and clinical conditions of periodontitis. Clinical parameters were Gingival Index, probing depth and tooth mobility, and occlusal sounds were assessed by the duration and wave patterns. Nine patients with moderate periodontitis were selected for this study.
Following a baseline examination, all participants were subjected to the treatment which was comprised of plaque control, scaling and root planing. Reexaminations were performed 1 week, 1 and 3 months after the completion of active treatment. The following results were obtained by this study:
1. The duration of occlusal sound was reduced with the improvement of periodontal disease conditions by the treatment. The duration of post-treatment was significantly shorter than that of pre-treatment.
2. In moderate periodontitis patients which had some increased mobile teeth and no occlusal trauma, the mean value of the duration was 14. 3 msec at pretreatment and 8.3-8.9 msec at post-treatment. The wave patterns of occlusal sound did show I-S type mostly at pre-treatment. After treatment, the changes occurred in the latter part of the wave, that is, the reduced amplitude of slide.

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The purpose of this study was to compare the difference between the rolling toothbrushing motion a newly designed brushing machine and three subjects who were skilled in the rolling toothbrushing technique.
The evaluation of the distortion curves of the rolling toothbrushing motion recorded by a tri-axial strain gauge attached to the shank of the toothbrush indicate the newly designed brushing machine reproduce the sufficient rolling toothbrushing motion.

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The brushing methods suitable for various abnormal form of periodontal tissue and malpositioned teeth in patients with periodontal disease are still not established. In this study the effect of different kinds of brushing methods on plaque removal for malpositioned teeth was investigated.
The impression of malpositioned (linguoversion) teeth and nonmalpositioned teeth in mandibular premolar regions were taken from two subjects and the resin models were prepared from the impression.
The artificial plaque originally prepared was spread on the teeth. Four brushing methods (Scrubbing method, Fones method, Charters method, modified Stillman method) were used to remove the supragingival plaque from the resin teeth. The rate of plaque removal was measured using standardized color photo devices before and after brushing.
The effect of different brushing methods on plaque removal on nonmalpositioned teeth was as follows ; Scrubbing>Fones>Charters>modified Stillman. While on malpositioned (linguoversion) teeth, Scrubbing method and Fones method showed significantly higher plaque removal (p<0.05) than Charters method and modified Stillman method. Scrubbing method showed lower plaque removal on malpositioned teeth (p<0.001) than nonmalpositioned teeth, but on Fones method, the same plaque removal was shown on the malpositioned teeth as the nonmalpositioned teeth.

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The purpose of the study was to establish a simple method of MTM, that can provide mesio-distal bodily movement of the furcation involved separated roots. The experiment was carried out on lower first molar teeth using artificial model. The roots were separated and fixed in typodont wax. The depth of the wax was made at 11, 8 and 4mm level, which was supposed to correspond to the level of bone resorption in a clinical situation. The components of the orthodontic appliance used were, piston screw (Dentaurum Co.) with guide wire (. O1mm), home made apparatus with wire (. O1mm), tube and coil. Orthodontic force was applied to expand interproximal space about 2 mm at C. E. J.. As the results, 1) The piston screw could easily adjust to the applied force. But tipping movement occured when screw alone was used, which also resulted small separation space at clinical cervix and was proportional to the bone level. 2) When the piston screw was combined with one guide wire, it was possible to accomplish bodily movement of the roots to an extent where interproximal cervix could be cleaned without difficulty. 3) The adjustment of the home made apparatus was a little difficult. But when properly adjusted, it could bring about bodily movement, therefore has a wide potential for clinical application.

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The purpose of the present study was to determine the degree of fitness between the blade of the Gracey type scaler and the tooth surface. Gracey type scalers of six makers and 90 periodontally involved extracted teeth were used for the study. The lengths and curvature radii of the scalers' blades were measured from above. The angles and curvature radii of the blades were measured from the side. The curvature radii of each tooth surface were measured from above at the cemento-enamel junction (CEJ) and 2mm apically from the CEJ (CEJ'). The curvature radii and the angles of the circular arc of each tooth were measured from the side at CEJ, CEJ'. The fitness between the scalers' blades and the tooth surfaces measured from above and the side atCEJ, CEJ' was a point-contact. The forms of the blades observed from above were nearly straight.

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Use of a free mucosal graft is an effective procedure in oral-area operations. However, little attention has been paid to the wound surface after removing the palatal mucosa, although this is one of the embarrassing questions regarding the actual operation.
In our technique lyophilized porcine dermis is applied with the fibrin adhesive paste to the wound surface after the palatal mucosa is removed and a plate made by a vacnum adapter is attached to the site. This method leads to ready hemostasis at the wound of the site from which the palatal mucosa was removed, little postoperative pain, release from stimulation at the time of ingestion, and further accelerated healing of the wound.

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The clinical usefulness of granule and block hydroxyapatite (HAP) in periodontal osseous defects was evaluated. Twentythirty patients having 30 intraosseous defects were selected. After initial preparation, a flap operation was performed, and granule or block HAP was implanted into the osseous defect. Clinical parameters were pocket depth (Pd) and clinical attachment level (Atg). Roentgenographs and photographs were taken before the surgery and 1 week, and 3, 12, 24 and 36 months after the surgery.
The ressults were as follows.
1. Clinical responses in patients in whom granule and block HAP were grafted have been good since 12 months after the implantation.
2. No marked difference in grafting was observed between the granule and block HAP materials.
These data suggest that granule and block HAP are clinically useful materials for grafting to periodontal osseous defects.

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