The present study attempted to explore the biochemical mechanism by which Diphenylhydantoin (DPH) induced gingival hyperplasia. The gingiva, palate mucosa, dosal skin and liver (250mg wet weight) collected from male Wistar rats at 3, 5 and 8 weeks of age were incubated in Krebs Ringer phosphate buffer solution (pH 7.4) containing Succinate -1, 4^-14C (5μCi/ml) with or without DPH (6.7μCi/ml) at 37°C for 120min. Then the radioactive organic acids, amino acids and non diffusible product of the tissues synthesized from succinate-1, 4^-14C were fractionated chromatographically and measured by scintillation counter.
The main organic acids synthesized the four tissues were fumarate and malate. Formation of fumarate was accelerated while malate synthesis was inhibited by DPH in gingival tissues. These results suggested that succinate dehydrogenase and malate dehydrogenase were activated and/or fumarate was inactivated by the action of DPH on gingiva. Amino acid synthesis in gingival tissues was inhibited by DPH particularly at the age of 3 week. Synthesis of macromolecules by gingiva was increased by 5 week. In comparison with gingiva, the other tissues showed specific but small changes.

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The present study was performed to clarify the relation between periodontal disease and prostaglandins (PGE₂, PGF_2α, PGE₁) in whole saliva (saliva). Saliva was collected from clinically healthy subjects and periodontally diseased subjects. Prostaglandin levels in the saliva were measured by high performance liquid chromatography (HPLC). Saliva was prepared by a modified Ueda et al. method using a reversed-phase column. In order to detect a small amount of prostaglandins in the saliva, a new HPLC method, applying a column switching technique, was developed by the author and Omori et al.. These methods enabled prostaglandins to be detected with high selectivity and sensitivity as compared with the traditional HPLC method.
The following results were obtained. 1. Standard curves of prostaglandins were linear in the range of 0.2 ng to 20 ng.
2. PGE₂, PGF_2α and PGE₁ levels in saliva from clinically healthy subjects were 0.7±0.5 ng/ml, 1.6±0.9 ng/ml and 0.8±0.5 ng/ml and those of periodontally diseased subjects were 1.8±0.8 ng/ml, 3.0±2.3 ng/ml and 1.7±0.5 ng/ml respectively. PGE₂ and PGE₁ levels in periodontally diseased subjects were significantly higher than those in clinically healthy subjects (p<0.001). But the PGF_2α level was not significantly different.
3. 1) PGE₂ level in the saliva was significantly correlated with clinical findings, such as GI, DI-S, CI-S, GBI, pocket depth (mm), tooth mobility and alveolar bone loss (%) (p<0.01).
2) PGE₁ level in the saliva was significantly correlated with all clinical findings except DI-S (p< 0.01 or 0.05).
3) PGF_2α level in the saliva was not significantly correlated with any clinical findings.

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In order to confirm the role of maltose, D-glucose, α-amylase and α-glucosidase in periodontal disease, the present study was performed to measure these levels in serum and in parotid, submandibular-sublingual and whole saliva from clinically healthy subjects (CH) and periodontally diseased subjects (PD).
Maltose and D-glucose levels were measured by high performance liquid chromatography, α-amylase activity was assayed by a blue starch polymer method and α-glucosidase activity was calculated by taking D-glucose level in sample from that after incubation.
The following results were obtained.
1. In serum, maltose, D-glucose, α-amylase andα-glucosidase of CH were nil, 845.23±253.20μg/ml, 0.17±0.05U/ml and nil, and those of PD were nil, 936.45±179.79μg/ml, 0.23±0.08U/ml and 1.97±2.68mU/ml, respectively. D-Glucose and α-amylase of PD were higher than those of CH.
2. In parotid saliva, maltose, D-glucose, α-amylase and α-glucosidase of CH were 2.43±1.53μg/ml, 14.85±12.87μg/ml 56.95±54.59μg/ml and nil, and those of PD were 1.39±0.60μg/ml, 6.63±9.10μg/ ml, 166.91±151.58U/ml and 0.05±0.12mU/ml, respectively. Maltose and D-glucose levels of CH were higher than those of PD and α-amylase activity of PD was higher than that of CH.
3. In submandibular-sublingual saliva, maltose, D-glucose, α-amylase and α-glucosidase of CH were 6.62±6.28μg/ml, 11.91±8.70μg/ml, 57.16±81.57U/ ml and nil, and those of PD were 24.56±19.21μg/ml, 37.94±25.78μg/ml, 46.48±67.74U/ml and 0.05±0.10mU/ml, respectively. Maltose and D-glucose levels of PD were significantly higher than those of CH (p<0.01) and α-amylase activity of CH was higher than that of PD.
4. In whole saliva, maltose, D-glucose, α-amylase and α-glucosidase of CH were 15.56±20.14μg/ml, 7.24±12.48μg/ml, 82.25±118.58U/ml and 0.43±0.48mU/ml, and those of PD were 31.80±27.51μg/ ml, 23.10±30.21μg/ml, 154.54±153.42U/ml and 0.99±1.68mU/ml, respectively. Maltose level of PD was significantly higher than that of CH (p<0 .01), and D-glucose, α-amylase and α-glucosidase of PD were higher than those of CH.
5. Debris Index was significantly correlated with maltose level in submandibular-sublingual and whole saliva (p<0.01).

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The purpose of the present study was to investigate macroscopically and histologically the relation between the effect of bacterial protease and that of diabetes on the wound healing of the gingiva in rats. Gingivectomy was carried out on the mesial side of the maxillary first molar, and the saline or the bacterial protease was applied on the gingival wound once a day for 7 days. The animals were sacrificed at intervals of 0, 1, 3, 5, 8, 11, 15, 22, 29 and 36 days after gingivectomy, and the periodontal tissues of the mesial side of the maxillary first molar were examined macroscopically and histologically.
The results were as following.
1. Saline application groups
1) Normal rats (Group-A) The blood glucose levels were 95.3±8.3 mg/dl, and the wounds were repaired at 11 days.
2) Alloxan diabetic rats (Group-C) The blood glucose levels were 345.6±41.1 mg/dl, and the wounds were repaired at 15 days.
2. Bacterial protease application groups
1) Normal rats (Group-B) The blood glucose levels were 96.7±11.5 mg/dl, and the wounds were repaired at 22 days.
2) Alloxan diabetic rats (Group-D) The blood glucose levels were 355.7±29.8 mg/dl, and the wounds were not repaired even at 36 days.

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The purpose of this investigation was to examine the immunobiological properties of lipopolysaccharides (LPS), mechanically disrupted fractions (M. D. F.), and extracellular products (E. P.) from Actinobacillus actinomycetemcomitans ATCC 29523, Y4, and SUNYaB67. Biological activities of these preparations were investigated in terms of mitogenicity, polyclonal B cell activation, adjuvant activity, and stimulation of interleukin 1 (IL-1) production in mice.
The results were as follows:
The LPS, M. D. F., and E. P. preparations from A. actinomycetemcomitans were mitogenic for mouse B lymphocytes. The LPS preparations induced mitogenic and polyclonal responses of LPS-responsive C3H/HeN mouse spleen cells, and enhanced in vitro immune responses to sheep erythrocytes. Spleen cells of C3H/HeJ mouse nonresponsive to enterobacteriaceal LPS were found not to yield these activities.
The M. D. F. and E.P. preparations from A. actinomycetemcomitans induced mitogenic responses of C3H/ HeN and C3H/HeJ mouse spleen cells. It was found that biological activities of M. D. F. and E. P. preparations were weaker than those of LPS preparations in term of polyclonal B cell activation. Furthermore, these preparations did not function as an adjuvant in C3H/HeN and C3H/HeJ mice.
All preparations from A. actinomycetemcomitans Y4 induced C3H/HeN mouse peritoneal cells to produce IL-1 activity.
These findings indicated that A. actinomycetemcomitans LPS induced a wide variety of immunobiologic responses. Therefore, the results suggest that A. actinomycetemcomitans LPS may play a significant role in the pathogenesis of periodontal disease.

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The purpose of the present study was to evaluate histopathologically following the use of β-tricalcium phosphate (TCP) in experimentally produced bony defects. TCP was implanted in experimentally created 2 walled and 1 walled vertical bone defects in 2 dogs. A three-colour labelling method with Tetracycline, Calcein and Alizarin red S was used to evaluate osseous repair of alveolar bone. Twenty one weeks after surgery, re-entry surgery was performed and the depth of defects was measured. Twenty five weeks after surgery, the animals were sacrificed for histological evaluation.
The result was as follows.
1. A three-colour labelling method was very useful to evaluate osseous repair.
2. In experimental site where TCP was implanted, mineral deposition was more complicated and continued longer compared to control site.
3. Ankylosis and migration of the junctional epithelium were not observed.
4. TCP particles were mostly resorbed 25 weeks after implantation.

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The present study was undertaken to evaluate the effect of porous hydroxylapatite granules on the healing of periodontal osseous defects in 4 monkeys.
Different types of periodontal osseous defects were prepared in two parts of the investigation.
In the first part, surgically created 3-walled osseous defects were filled with porous hydroxylaptite granules in the period of 8 and 12 months in order to evaluate the long-term effect of porous hydroxylatite granules on the healing of periodontal osseous defects. Histological sections showed minimal apical migration of the junctional epithelium, regeneration of new cementum, and large amount of bone formation.
In the second part, 3-walled osseous defects with plaque-affected roots were prepared, and filled with porous hydroxylapatite granules in the period of 2, 4, and 12 weeks. As a control, defects were treated in the same procedure without filling the granules. Histometric comparison on the sections of experimental sites and controls showed that new bone formation was similar for both sites but the apical migration of junctional epithelium was suppressed in the experimental sites.
These data strongly suggested that this material could be applied in periodontal bone defects as clinical use.

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The thin layer of cementum exposed in the oral environment may be readily lost as a result of routine tooth brushing and periodontal therapy such as scaling and root planing. It is obvious that the dentin reacts sensitivity to acid, thermal change and scratch.
The purpose of this investigation was to find the relationship between the various stimuli such as cold water, warm water and tactile stimulation and the degree of cervical hypersensitivity and to futher evaluate the pathological changes in the dental pulps of these teeth.
One hundred and eight caries-free permanent teeth were collected from patients, ranging in age 19 to 60, diagnosed as having advanced periodontal disease. All subjects had negative history for systemic disease and present illness other than periodontal disease and cervical hypersensitivity. At first, the amount of calculus, width of exposed root surface and degree of abrasion were determined clinically by visual examination. Immediately after marking on the degree of the hypersensitivity to cold water, warm water and tactile stimulation, experimental teeth were extracted and prepared for pathological findings.
Clinical findinds obtained from this study were as follows:
1. In hypersensitive group to cold water, All subjects complained of mild sensitivity, but the degree of hypersensitivity was inclined to become worse with the increase of the amount of calculus.
2. In hypersensitive group to three stimuli, severe hypersensitivity was observed in many cases with the increase of the width of the disposed root surface.
3. 76 out of 108 teeth had abrasion such as Vshaped defect, and almost all of them were observed moderate or severe hypersensitivity. Pathological changes in the dental pulp revieled in this study were surmarized as follows: (1) Disappearance of predentin (2) Disappearance of odontoblast (3) Reticular atrophy (4) Formation of denticle (5) Caltification (6) Hyperemia (7) Bleeding (8) Abcess formation (9) Pulp necrosis (10) Round cell infiltration (11) Formation of secondary dentin.
1. In the sensitive group to cold water and both cold and warm water, the restorativre change i. e. the formation of secondary dentin was observed in many cases.
2. In the sensitive group to both cold and warm water, reticular atrophy and hyperemia were inclined to increase clearly.
3. In the sensitive group to three stimuli, if the clinical symptom was mild, hyperemia was the chief cange in the dental pulp. In the case of severe hypersensitivity, however, the destructive changes such as round cell infiltration and abcess formation were inclined to increase. It was suggested that the intrapulpal changes would be serious and complicated with the increase of the stimulating factors and the degree of clinical symptom.

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In previous study, it was demonstrated that an adhesive glycoprotein of fibronectin is included in salivary flow, and suggested that fibronectin played a role of the formation of acquired enamel pellicle, dental plaque and calculus.
In this study, the fibronectin was investigated in vitro system at physiological temperature as to its adsorption behavior onto hydroxyapatite in phosphate solution in comparing with albumin (control).
The affinity of fibronectin to hydroxyapatite was considerably greater than that of albumin. The adsorption isotherm by measuring the amount of fibronectin adsorbed was well approximated by that of Langmuir. From the results, it was proved that the fibronectin in salivary flow adsorbed onto enamel surface to form acquired enamel pellicle.

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The aim of this study was to investigate the biocompatibility and the osteoconductivity of hydroxyapatite block (HAP-B), prior to its clinical use as bone graft material for one wall or horizontal bone defects.
To observe HAP-B's biocompatibility, hydroxyapatite granules (HAP-G), of which HAP-B was made, were implanted into left M. rectus femoris of rats. Each rat was sacrificed two, four, twelve and twenty-four weeks after implantation. Further HAPB's osteoconductivity was researched. Previous to implantation, both sides of P₂ and P₄ in beagle dogs were extracted. Three months after extraction, artificial bone defects were prepared at the mesial sites of P₃ and M₁. HAP-Bs were implanted into the mesial sites of M₁ and not into those of P₃ as control. Two, four, eight and twelve weeks after implantation, beagle dogs were sacrificed and their mandibles were biopsied for light microscopic study.
The results obtained were as follows.
1. All through the experimental period, HAP-Gs had been encapsulated by fibrous connective tissue involving foreign body giant cells and/or macrophagelike mononuclear cells. But HAP-Gs had been isolated from muscular tissues which showed no damage.
2. There were no pathological findings in liver, spleen, kidney, heart, lung and adrenal gland in rats.
3. The wound healing of subepithelial connective tissue and alveolar bone was almost finished twelve weeks after implantation in both control and experimental sites.
4. Newly formed bone tissues and osteoids attached directly to HAP-B and woven bone formation was noted also in connective tissues among HAP-B.
5. The external form of the regenerated alveolar bone of control showed a hollow at mesio-distal center, but that of experimental site was similar to anatomical feature. Haversian systems existed also in the regenerated alveolar bone involving HAP-B.
Considering above-described results, HAP-B had fine biocompatibility and osteoconductivity, and brought more natural feature to bone repair. Consequently HAP-B were much expected to be effective on clinical use as bone graft material.

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Seventy-five patients who participated in a clinical study comparing the response of periodontal osseous defects to either grafting with Periograf® ceramic or debridement only were followed under an active maintenance program for six-months. Various clinical examinations were performed before the surgery, during the surgery, 1 week, 1, 3 and 6 months after the surgery.
The results are as follows.
1. In the experimental groups, the mean values for gingival recession, gain of attachment level, decrease of pocket depth and roentgenographic bone fill were respetivery 1.8 mm, 2.0 mm, 3.7 mm and 62.2% at six months postoperativery.
2. In control groups, the mean values for gingival recession, gain of attachment level and decrease of pocket depth were respetivery 1.9 mm, 0.8 mm and 2.7 mm
3. Hard tissue changes and soft tissue changes demonstrated a substantial advantage for use of Periograf ® over controls.

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The effects of diphenylhydantion (DPH) on DNA, RNA, and protein synthesis in cultured bovine gingival explants were investigated. Explants were supported by siliconized lens paper at the surface of chemically defined synthetic medium (M-199).
DPH, at a concentration of 5μg/ml of medium, caused increase of DNA synthesis in three cases of six separate experiments. Furthermore insulin and dexamethasone significantly augmented the stimulatory effect of DPH on DNA synthesis. These three cases in which DNA synthesis were enhanced were named “Responder group”, and other three cases “Non -Responder group”. In “Responder group” RNA synthesis was also stimulated by DPH, but not in “Non-Responder group”. Protein synthesis was not affected by DPH in either group.
These results suggest that DPH is involved in the regulation of cell proliferation in cultured gingival explants.

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Effects of nifedipine, an anti-anginal drug, and EGF, one of the growth factor which exists in saliva, on growth and DNA synthesis of human gingival fibroblasts were studied.
Using standard cell culture technique, gingival fibroblasts were derived from patients taking nifedipine with (Responder) or without (Non-Responder) Dilantin-like gingival hyperplasia. Cells from Responder showed less proliferative activity than those from Non-Responder. The presence of nifedipine during the cultured period did not show any proliferative effects on the cells tested in this experiment. Both the Responder and Non-Responder cells were not significantly sensitive to EGF on DNA synthesis as compared to the control cells.
In addition, the content of EGF in saliva did not have any difference between Responder and control.

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The role of oxalic acid in salivary stone formation has not been established yet. This study was performed to determine the amount of oxalic acid and calcium in salivary stone.
Oxalic acid level in salivary stone was fractionated by high-performance liquid chromatography (HPLC) using a two column switing system and determined spectrophotomerically by converting it into 2-nitrophenylhydrazine, a method developed by Horikawa et al.. The minimal detectable amount of oxalic acid was 0.2n mol, and the recovery was 92% in this system.
Samples were collected and mixed with 0.5 ml of 1.0 N HCl and the mixture was allowed to stand for one hour. Two ml of H₂O was added to the reaction mixture and was then filtered through an ultrafiltration menbrane (Immersible CX-10®). The filtrate was then injected onto the HPLC system.
Oxalic acid and calcium levels in salivary stone were 7.25±3.63n mol/dry weight mg.±S.D. and 264.7±58.4 Eg/dry weight mg, respectively. It was concluded from these results that oxalic acid was closely related to the formation of salivary stone.

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Although Langerhans cell (LC) is one of the important immune cells, the function of LC still remains indistinct in periodontitis because of few reports about it. In order to explore the roles of LC in periodontitis, we studied on the movement of LC population in oral epithelium through patients' generation and the degrees of inflammation.
For this study, fifty-two patients with periodontitis were selected and their gingiva of seventy-eight lesions were biopsid at surgical treatment or tooth extraction. The clinically healthy gingiva and gingiva affected by gingivitis were used as control. The patients were divided into three groups by their age; younger, middle and older generation. LCs were indicated immunohistochemically by their reactivity to S-100 protein. The ratios of LCs to epithelial cells by number were determined in each generation and in each degree of inflammation.
The results obtained were as follows.
According to the severity of inflammation, the number of LCs tended to increase in every generation. Comparing the ratios of LCs in periodontitis with those in control, only in older generation significantly higher ratio was observed. Further there was no difference in younger generation.
The results indicated that LCs functioned as antigen-presenting cells also in inflammed gingiva. In addition, a possibility was suggested that the conditions of inflammation in younger generation were slightly different from those in other generations.

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The establishment of an increased zone of attached gingiva is still considered to be an important aspect of periodontal therapy.
The purpose of this study was to evaluate the observation on wound healing, in comparison with autogenous free gingival surgery, of free transplantation procedure by using of lyophilized dura mater
“Lyodura” in the mucogingival surgery .
The animals were sacrificed at 1, 7, 14, 42 days after surgery.
The histological examination was performed in buccal gingiva of premolars and molars on 5 adult dogs.
Histological findings indicated that the numerous number of fibroblasts migrated in group and with collagen fiber in the Lyodura-collagen structure.
It demonstrated a remarkably consistent rate of epithelization 3 to 7 days post operative, regardless of variations in host or technique.
Rapidly and finaly the grafted Lyodura were replaced on connective tissue in 14 days.
It was desirable to evaluate gingiva healing by using of Lyodura in order to get a zone of stable attached gingiva.

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Experiments were performed for the purpose of investigating what change the form of healing undergoes when fibrin formability has been altered artificially by the use of GT-13 which is a material enhancing the local accumulation of fibrin network in periodontal surgery.
In addition to making presentation of the material enhancing the local accumulation of fibrin network, basic studies were conducted, this time, of amount of fibrin formation, connective strength of the formed fibrin with the peripheral tissue, time of fibrin formation and its reaction with the peripheral tissue.
As a result, it was learned that the material enhancing the local accumulation of fibrin network has characteristics such as (1) its manipulation is very simple, (2) it can be immobilized in various carriers for application to the wound, (3) it has good affinity with the peripheral tissue, forming a fibrin network at an early stage and maintaining it.
Thus, it was suggested that this material is an element effective for determing how fibrin participates in the process of wound healing after periodontal surgery.

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We made an investigation concerning the general status of patients, especially about the changes of blood pressure, while they are under flap operation.
33 patients (22 males, 11 females) having normal blood pressure and who were diagnosed as chronic marginal periodontitis were chosen as subjects. These subjects recieved initial preparation in advance of flap operation.
Blood pressure changes during flap operation were recorded by an automatic sphygmomanometer (UEDA Co. USM-205).
The recordings of blood pressure changes were made at the begining of each operational steps, also every five minutes during the operation and at 30 minutes post operation. We chose the value of blood pressure at the point of 15 minutes after relaxed position before the operation began, as the initial value of blood pressure.
From above study we have obtained the following results.
1. The use of 2% lidocaine containing 1 : 80000 concentration of epinephirin as the first local anesthesia, increased the systric and diastric pressure meaningfully. The percentage of blood pressure increase were 6.8% and 5.1% respectively.
2. During the operation, both the systric and diastric blood pressure maintained high value as same as its initial value which was taken at the begining of the operation. Furthermore, both blood pressure increased when root planing began but the standard deviation of increased percentage seemed to be wide spreading.
3. Compared to the pressure recorded right after the operation, the systric blood, pressure decreased and diastric blood pressure increased 30 minutes after the operation. But both the systric and diastric blood pressure did not resume to their initial value which was recorded before operation.
4. The avarage increasing rate of the systric pressure was 6.0% and the diastric pressure was 4.3% during the operation.

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The purpose of the present study was to evaluate the effect of a new dentifrice containing lysozyme chloride and sodium fluoride on periodontal disease by the double blind test.
Sixty-seven students with gingivitis were directed to clean the teeth with the dentifrice for four weeks. They were devided into three groups; using placebo dentifrice (control group), using dentifrice containing chlorhexidine (chlorhexidine group) and using dentifrice containing lysozyme chloride and sodium fluoride (lysozyme group).
In three groups, redness, swelling of gingiva, depth of periodontal pockets and bleeding on probing were improved during whole experiment. Significant difference was observed in the percent improvement of the redness and the swelling between the lysozyme group and the others (x^2-test).
It suggests that the new dentifrice possessed a part of an anti-inflammatory effect. The use of this dentifrice may enhance the clinical effect of toothbrushing on periodontal disease.

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This study was conducted on 6 dentists to compare the relative efficacy of Viadent ® oral rinse/toothpaste containing 0.01% sanguinarine and 0.2% chlorhexidine aqueous- solution on plaque formation. Following an initial examination, all subjects received a professional tooth cleaning. The subjects then were asked to continue their own daily oral hygiene procedures throughout the experiment. The experiment consisted of 3 periods. The subjects rinsed twice daily for 2 weeks with Viadent ® oral rinse (10 ml, 30 sec). After 2 weeks, the Plaque Index. was recorded and they received a professional tooth cleaning. Following 2-week interim period, they rinsed for 2 weeks with 0.2% chlorhexidine solution (10ml, 30sec). After 2 weeks, the Plaque Index was recorded and they received a professional tooth cleaning. Following 2-week interim period, they were asked to rinse 5 times daily with Viadent ® oral rinse and to use Viadent ® toothpaste at their brushing time.
The result of this study suggested that twice daily use of either Viadent ® oral rinse or 0.2% chlorhexidine solution, and five times daily use of Viadentco oral rinse+Viadent ® toothpaste at brushing time as an adjunct to the subjects' own daily oral hygiene produced the plaque inhibiting activity. However, the data demonstrated that its activity of 0.2% chlorhexidine rinse was significantly more pronounced than that of Viadent ® oral rinse and toothpaste. Side effects such as brown staining of teeth and tongue, and unacceptable taste were found in the subjects with 0.2% chlorhexidine rinse. However, the use of Viadent ® caused only a few side effects.

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An automatic oral cleaning apparatus for hospitalized handicapped petients was developel and its clinical application was investigated. The apparatus consisted of an air-driven vibratory toothbrush, an oral irrigator and an aspirator which were supporLed by a two-jointed arm attached to the side of the mobile body. Two Collis' curve brush tips were connected, back to back, as a brush for this apparatus.
Twelve dental students and 17 hospitalized patients of progressive musclar dystrophy were the subjects of this investigation. The plaque score was measured using neutral red staining method. The plaque index used was modification of Harrap's and Cohen's method.
The index of experimentally accumulated plaque was 2.1 in the student group and decreased to 1.3 after 3 minutes use of this apparatus. Experimental accumulation of plaqe was not adopted on the patient group. The initial plaque score of 3.8 in patient group decreased to 2.1 after the use of the apparatus.
The proximal surface of teeth and abnormal arrangement teeth were the most difficult sites to remove plaque by the apparatus.

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The purpose of this study was to assess a change of plaque control record score by O'Leary et al. during initial periodontal treatment. One hundred and fifty-eight patients, (98 females, 58 males), aged 18 to 72, averaged age 42. 2) with slight and moderate degree of periodontal disease, were given oral hygiene procedures including mainly toothbrushing instruction (TBI) and flossing with 10% or less of plaque accumulation level for a goal. A toothbrushing method and time, plaque control score and any other comments were recorded.
The following results were obtained in this study. (1) Before TBI, 24% of patients used the scrubbing methd, and 72% of patients brushed their teeth for only short brushing time under 3 minutes. (2) Ninety-two percent of patients achieved plaque control record score of 20% level after 4.6 times of TBI, and the mean toothbrushing time was 8.6 minutes. Fifty-eight percent of patients accomplished plaque conrtol record score of 10% level after 5.9 times of TBI, and the mean toothbrushing time was 9.8 minutes. 3) Plaque control was difficult in especially posterior, lingual and proximal tooth surfaces.

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This study was performed to examine if undesirable relationships between mandibular height, tooth crown lenght, root length and crown to root ratio may influence on the etiology of periodontal bone resorption.
One hundred films of orthopantomographs were taken from patients with gingivitis and with light or moderate periodontal disease were used. Those patients were aged from 16 to 78, 44 males and 56 females. On film, anatomical crown and root length were measured for lower incisors, canines and premolars. Then, crown-root ratio and bone destruction were calculated. The anatomical crown-root ratio was determined by measuring the level of cementenamel junction. The bone loss from the cement-enamel junction was measured in percentage. The mandibular height was measured from cement-enamel junction of each tooth to mandibular plane also. The measuring was carried out by three trained examiners.
The results were as follows in this study.
1. The tooth length had a tendency to be decreased with increasing age.
2. The periodontal bone had a tendency to be destroyed with increasing age.
3. The mandibular height showed an increase with aging.
4. There was not a statistically significant correlation between crown-root ratio between age groups.
5. There was not a statistically significant correlation between mandibular height and bone resorption.

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To determine accurately the approximate amount of bone destruction and either horizontal or vertical resorption, it is necessary to utilize _??_ or _??_ 41 6 6 14 dental radiographs on 972 outpatients of Niigata Dental Hospital.
As a result, bone destruction increased with increasing age. There were trends towards more bone destruction in males than in females and in lowers than in uppers. The upper first molars exhibited most severely vertical bone loss.

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This study was performed to examine the relationship between the partial recording method of six representative teeth by Ramfjord and the entire dentition recording method for pocket depth, remaining bone level and tooth mobility.
Subjects were 150 periodontal patients aged 18 to 62, averaged 36.3 years, 59 males 91 females, who visited our hospital from 1982 to 1984.
Moreover the relationship between the mean of each group (_??_) and the mean of the represantative individial tooth in each group was assessed.
From the fact described above the following results were gained in this study.
1. Statistically significant difference was not observed between the six selected teeth discribed by Ramfjord and the entire dentition for every items.
2. Statistically singificant difference was not observed between the mean of the each group and the mean of the represantative tooth in each group.
3. Ramfjord's method was a reliable partial recoding method, and if the represantative tooth was missing in each group another tooth was avaiable for the represantative tooth.

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The purpose of the present study was to evaluate longitudinally the effects of periodontal therapy on periodontium of young patients during orthodontic therapy. Twenty-four patients who had malocclusion in their anterior teeth and high inflammation in their periodontium were selected.
Before starting therapy, their periodontal conditions were examined according to Gingival Index, probing depth, width of keratinized gingiva, width of attached gingiva, tooth mobility and plaque control record.
During orthodontic therapy, all patients were recalled every month, and enforced the significance of plaque removal and motivated. After 2-3.5 year of active treatment and maintenance, the following results were obtained.
1. The Gingival Index score decreased from 1.32.± 0.48 to 0.23.± 0.48 (p<0.001)
2. Probing depth decreased from 2.10.± 0.70mm to 1.88.± 0.64mm (p<0.001)
3. Width of keratinized gingiva increased from 3.76.± 1.24mm to 3.99.± 1.20mm (p<0.001)
4. Width of attached gingiva also increased from 1.72.± 0.94mm to 2.45.± 1.01mm (p<0.001)
5. Tooth mobility decreased from 0.37.± 0.50 to 0.04.± 0.20 (p<0.001)
6. Plaque control score decreased from 86.3.± 17.0% to 35.1.± 28.0%. However, the decrease rate was not constant and there were great variations in patients.
In conclusion, it was revealed that long term maintenance of periodontium was prerequisite for young patients in orthodontic therapy and regeneration of tissues would be expected by co-operative perioortho therapy.

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This study was carried out to analyze the effects of initial preparation on 143 patients with periodontal disease using the computer system. The initial preparation consisted of plaque control, scaling, gingival curettage, occlusal adjustment and temporary splinting.
The results showed that plaque score, Gingival Index and tooth mobility decreased dramatically after the initial preparation. The deep pockets in 4-6mm and 7-10mm significantly decreased and its mean changed from 4.6±0.8mm to 2.4±1.2mm and from 7.9±1.0 to 3.1±1.6mm, respectively (p<0.001).
However, the values of pocket reduction were small at furcation involved sites. 0.3-1.7mm gain in clinical gingival attachment was obtained through the initial treatment.

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Clinical and immunopathological studies were performed on 8 patients with severe periodontitis but without any evidence of systemic disease. The patients consisted of 5 females and 3 males, between the ages of 18 and 26 years. Four patients (3 females and one male) were diagnosed as generalized periodontal destruction and the another 4 (2 each in both sex) as localized periodontal destruction on the basis of radiographic measurement of alveolar bone destruction. The latter 4 patients have more teeth involved than incisor and the 1st molars.
Abnormal serum levels of IgM, IgG and IgA were detected in each patients. Higher IgM level was found in 5 patients, higher IgG was in 2 patients, higher IgA in one and lower IgA was another 3 patients. High ASLO was detected in one patient. High ASLO recovered to normal level after periodontal treatment. Periodontal treatment also diminished high IgM and IgG levels within normal limits in some patients, but did not in the others.
Histological and immunofluorescent quantitation of Ig bearing lymphocytes and Ig positive plasma cells was assessed. The predominant Ig staining cells present were IgG, followed by IgA and IgM. IgM bearing cells were very few. The ratio of plasma cells to lymphocytes was 3 to 2 in localized type, and 4 to 1 in generalized type.
The proportion of T cell subsets was calculated in gingival lymphocytes eluted from inflamed gingival specimen. The percentage of OKT4⁺ and OKT8⁺ cells in T lymphocytes was 46.5±0.2 and 29.1±6.7%. The incidence was similar to that in adult periodontitis reported by us. However, the frequency of OKIal⁺ T cells (12.0±2.2) was much lower than that in adult periodontitis.

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Neutrophil and monocyte chemotactic response were evaluated in eight patients with severe periodontitis, aged in the range from 18 to 26 years. On the basis of clinical and radiographic measurements, four patients were classified generalized type, and four were localized type. The chemotactic response was measured by a membrane filter method using a multiwell chemotaxis assembly, and patient's peripheral neutrophils or monocytes were compared with those of control healthy subjects, using N-formyl-Lmethionyl -L-leucyl -L-phenylalanine and endotoxin activated human serum as the standard chemoattractants.
Based upon statistical analysis of chemotaxis assays, neutrophil chemotactic response was significantly elevated in one of four generalized type patients.
In four localized type patients, one patient showed elevated neutrophil chemotactic response, and two patients exhibited depressed chemotactic response. In four generalized type patients, one patient exhibited depressed monocyte chemotactic response, and elevated monocyte chemotactic response was found in one patient. In four localized type patients, two patients showed depressed monocyte chemotaxis, and these patients had neutrophil defect together.
The effect of periodontal treatment on neutrophil and monocyte chemotaxis was studied in two localized type patients. In these patients, depressed neutrophil and monocyte chemotaxis were observed before and after periodontal therapy.

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Clinical, microbiological and immunological studies were performed on a family in which two daughters were affected by juvenile periodontitis and their mother had generalized severe periodontitis.
Clinical observation included assessment of inflammation, plaque, probing depth and bone loss. Elder sister, a 20-year old Japanese, was diagnosed as generalized periodontal destruction. Younger sister 18-year old, who in addition to having juvenile periodontitis is an epileptic, was diagnosed as localized periodontal destruction, whereas she had more teeth involved than incisors and first molars. The number of remaining teeth of 48-year old mother was seven, since many her teeth had been extracted because of loose teeth .
Subgingival plaque bacteria were sampled from the sisters before and after periodontal therapy, and the bacterial composition was examined individually by dark-field microscopy. Relatively high proportions of spirochetes and motile rods in periodontal pockets of the sisters were revealed. By periodontal therapy, the percentage of spirochetes and motile rods decreased from 42% to 22% in the elder sister and from 26% to 16% in the younger sister, on the contrary, the percentage of coccoid cells increased in the sisters.
Neutrophil and monocyte chemotactic response in the sisters and the mother were compared with those of control healthy subject. Based upon statistical analysis of chemotaxis assays, depressed monocyte chemotactic response was found in all of three subjects, whereas depressed chemotactic response was detected only in the younger sister. Depressed neutrophil and/or monocyte chemotactic response in the sisters were observed before and after periodontal therapy.
The proportions of T cell subsets in peripheral blood lymphocytes (PBLs) of the sisters and the mother were compared with those of control healthy subjects. The percentages of T cell subsets in freshly isolated PBLs were not different among them. After 7 days culture of PBLs without any stimuli, the percentages of OKIal T cells in the sisters were lower than that in the mother or control subjects.

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In an attempt to dentermine how the degree of the experimental stain removal and roughness of the metallic plate would be affected by ultrasonic scaler, hand scaler and air-power abrasive system instrumentation, quantitative measurement and morphological studies were made.
The results obtained were as follows:
1. On the stain removal, air-power abrasive system was the largest effect, followed by ultrasonic scaler and hand scaler.
2. On the roughness of the metallic plate, hand scaler was the largest defect, followed by ultrasonic scaler and air-power abrasive system.
3. Like rippling waves under ultrasonic scaling and stripes under hand scaling were observed on the scanning electron microscope.

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This investigation was undertaken to compare Periotron ® and Periotron Economy® by measured different kinds of samples. Further, as clinical examination, amount of gingival crevicular fluid (GCF) was measured by Periotron Economy. GCF was taken from upper anterior labial crevice. Also, Plaque Index (PlI), Gingival Index (GI), Gingival Bleeding I (ndex GBI) and probing depth (PD) were recorded as clinical parameters.
The results were as follow:
1. In quantity of human serum, distilled water, 0.1M-NaCl, 0.1M-CaCl2, 0.1M-MgCl₂, and 0.1 MKCl, Periotron and Periotron Economy were approved significant difference (p<0.01). And Periotron Economy were approved higher measurement than Periotron.
2. In 15 patients with periodontal disease under initial preparation, the significant correlation was found between amount of GCF andPlI, GI and GBI (p<0.01), but PD was not.
3. In 5 patients with periodontal disease who were examined before motivation and tooth brushing instruction, and recorded weekly changes under plaque control. Amount of GCF, PlI and GI were approved a decreasing tendency with the passage of weekly, but GBI and PD were not approved the change.
4. In 5 volunteers who were attacked experimental gingivitis for 14 days, as regards to amount of GCF, PlI and GI were approved an increasing tendency with the passage of every three days, but GBI and PD were not.
From these results, in the diagnosis of periodontal disease, measuring the quantity of GCF with Periotron Economy ® was turned out the effective method on elucidating condition of disease and suggested diagnosis possibility.

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No single report has been made concerning the time estimation required for periodontal examination and treatment in Japan. But in order to plan precisely to meet the periodontal needs of the population, it is necessary that the dimensions of the problem be defined with some degree of accuracy. The time required for plaque scoring, pocket depth measurement, plaque control, scaling, temporary splinting and flap operation, and other incidental conditions were investigated using a questionnaire. 29 dental colleges and university dental schools, 13 private clinics were asked to respond for the investigation. The number of answers from each questionnaire differed by question content, but the average was 381.4 per item.
As results, in all of the institutions, the average time necessary was as follows: Plaque score marking using O'Leary's plaque control record 12.8±6.8 min., Pocket probing (full mouth) 19.3±10.3 min., Occlusal examination 26.1±23.8 min., Plaque control 36.8±19.4 min., Scaling (one sextant) 39.9±29.9 min., Temporary splinting (one sextant) 33.2±17.7 min., Flap operation (one sextant) 87.3±29.1 min..
The average obtained in this study and in other studies in other countries were compared.

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