In study of the effects of NaF on bone metabolism in vivo and in vitro, it has been reported that NaF stimulated the bone remodeling and the bone cell activity or inhibited the bone resorption. However, the mechanisms of NaF action on the bone formation have not been clearly identified. Therefore, this study determines the direct effects of NaF on the bonelining cells from chick calvaria.
Two cell populations were obtained from 16 days old fetal chick calvaria as described by Nijweide et al. and Aubin et al. one cell population from periosteum (PF cells) and the other from periosteum-free calvaria (OB cells) were isolated with the enzymatic digestion and cultured separately. As control cell line of osteoblastic cells, a rat osteosarcoma cell line, ROS 17/2.8 B (ROS cell) was used.
The following items were investigated to evaluate and compare the effects of NaF on the above three cell lines: cell growth, alkaline phosphatase (ALPase), acid phosphatase (APase) and tartrate-resistant acid phosphatase (R-APase) activities, and protein synthesis.
The following conclusions obtained:
1. NaF did not stimulate the cell growth of three cell lines.
2. NaF did not stimulate ALPase activities of three cell lines, however, TR-APase activities were stimulated on OB cells.
3. NaF stimulated ALPase activities of PF cells which cultured 50% of the conditioned media of OB cells.
4. NaF stimulated the synthesis of 80 KD protein of OB cells.
5. NaF inhibited the osteonectin synthesis of PF cells. In conclusion, the direct effects of NaF on bone formation were not recognized on bone-lining cells from chick calvaria in vitro, except for the stimula. tion of TR-APase activity in OB cells and the cell differentiation of PF cells cultured with conditioned media of OB cells. This might suggest that NaF had indirect effect on the cell differentiation of PF cells to osteoblastic cell line.

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The purpose of this study was to evaluate the effect of the roughness of the surface for cell attachment and growth of the cultured cells in order to clear the mechanism of the attachment to the periodontally involved root surface.
Root surface was scaled with a ultrasonic scaler or was planed with Gracey curette. The roughness of each surface was measured with a profilometer (Surfcom 2000) for the purpose of comparing another sample surfaces which were produced by several types of the sandpaper (# 100, # 240). The following samples were used in this study: cementum or dentin surfaces (CS, DS) which were treated with two types of the sandpaper (CS-# 100, CS-# 240, DS-# 100, DS-# 240), scaled (SC), root planed (RP) and no treated (NT) surfaces.
Following the sterilization of each sample, the cultured epithelial cell line (Ca9-22 cell, Sq-1979 cell) were incubated on each of them for 24, 48, 72 and 96 hours. Finally, they were examined under the light microscope and/or the scanning electron microscope (SEM).
1. The number of cell attachment on the smooth surface was higher than that of the rough surface. With increasing the incubation time, the number of the cultured cells on RP was increased. However, it was lower than that on DS-# 240.
2. According to SEM observation, rough surfaces (CS-# 100, DS-# 100 and SC) and NT showed some inhibition for the growth of the cultured cells. On the other hand, smooth surfaces (CS-# 240, DS-# 240 and RP) gave better conditions for the cell culture.
3. Root planed or more smooth surfaces indicated a good result for the cell attachment and growth.

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The purpose of this study was to investigate the physicochemical changes in the exposed cementum from periodontally diseased human teeth. The physicochemical examinations were microhardness measurement, chemical composition analysis, crystallinity evaluation by X-ray diffraction and histochemical analysis by polarizing microscopy, microradiography and microanalysis.
The results were as follows:
1. No significant differences in microhardness were observed between exposed and unexposed cementum.
2. The carbonate content estimated by infraed absorption spectrum analysis was lower in the exposed cementum from the surface to a 20μm depth than in the corresponding area of unexposed cementum, whereas the fluoride content was higher in the exposed cementum from the surface to a 40-μm depth than in the corresponding area of unexposed cementum. Improvement of crystallinity was observed in the exposed cementum from the surface to a 20-μm depth. This improvement was attributed to a decrease in lattice defect. From the surface to a 50-μm depth of the exposed cementum, a hypermineralized zone and disordered collagen fibers, accompanyied by cracks, were observed. as morphological changes. These findings indicate that changes in physicohemical properties are restricted to the surface area of exposed cementum.

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There have been many hypothesis on the process of recirculation, certainly the essential factor for a graft “take” (1) One theory claims that recirculation starts with the anastomosis of a graft and the vessels of the graft bed; (2) There is the hypothesis that recirculation starts with the penetration of a graft by newly-formed vessels sprouting from the recipient bed; (3) Then there is the hypothesis which explains that recirculation starts by the combination of processes (1) and (2). In this study, the process of recirculaton in 28 adult mongrel dogs, which were subjected to free gingival autograft, was observed. Specimens of vascular corrosion casts on the 1st, 2nd, 3rd, and 5th day after grafting were examined under a scanning electron microscope. At the same time, investigations into pathohistology and ultrast ructure were made for comparative studies as well as to develop a theory concerning three-dimensional vascular architecture.
On the postoperative 3rd day, the results of resin injections indicated that vascular structure developed 3/4 area of the graft from the edges. On the postoperative 5th day, the injection was observed to be all over the graft, reaching the capillaries under the epithelium. Basically, the construction of the capillaries were almost identical to the loop construction indigenous to the gingiva.
At the graft-bed junctions, existing vessels of the graft communicated with vessels in the recipient bed with newly-formed sinusoidal vessels. These new vessels still retained mesenchymal characteristics, being formed by the multidimensional differentiation of undifferentiated mesenchymal cells into the pericyte of the endothelium. In the existing vessels of the graft and the vessels in the recipient bed, as well neither mitosis, migration nor wandering of the endothelial cells were observed. This served to indicate that recirculation to the graft is completed through the newly-formed sinusoidal vessels.

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The purpose of this study was to evaluate the effect of topically applied Paste containing 20% guaiacol (Gu-JG) on gingivitis and marginal periodontitis in humans and on experimental periodontitis in dogs.
The bleeding index was mainly used as the clinical parameter of gingival inflammation. Bacterial plaque samples were examined under a dark-field microscope.
The bleeding index for the group theated with Gu-JG was less than that of the untreated group in gingivitis and marginal periodontitis in humans. In experimental periodontitis, Gu-JG was effective in reducting the bleeding index, gingival index, probing depth and gingival crevicular fluid flow. Changes in microbial composition, i. e. reduction in the proportion of spirochetes and motile rods, were observed only in the pockets in which GU-JG was administed. Antimicrobial activity of GU-JG against B. gingivalis, C. ochracea and H. actinomycetemcomitans was observed in vitro.
It was concluded that Gu-JG had an anti-inflammatory effect mainly due to inhibition of microbial growth in periodontal pockets.

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Granule and block hydroxyapataite (HAP) materials were prepared, and clinical and histological studies were made of their physicochemical properties and of their usefulness as bone-grafting material for one and two-wall periodontal bone defects in the bone cavity. HAP materials thus prepared were pure, and HAP proved to be a porous body which has nondirectional, continuous pores and appropriate bonding strength, and is excellent in operability. For grafting to periodontal bone defects, both HAP materials presented much bone regeneration in their massed layers, and even 18 months after grafting there remained around HAP material immature tissue which was present in the connective tissue. Both HAP grafting materials showed less epithelial down growth and presented connective tissue adhesion independent of the cementum and periodontium-like tissue around the root, resulting in better periodontal tissue than with out grafting. No marked difference in grafting was observed between the granule and block HAP materials, and their usefulness was suggested for one- and two-well periodontal bone defects.

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The present study was aimed at developing an experimental model for histopathological understanding of the process of development of gingivitis from the normal gingiva and at determining the relation between response of the gingival epithelium to inflammation and deepening of the gingival sulcus (pocket formation).
In the experiments, the right and left large salivary glands were extirpated from male Wistar rats to disturb the self-cleansing action. The effects of ingestion of solid or powdered food on the periodontal tissue were determined for the palatal gingiva at the upper first molars at 1, 2 and 4 weeks and 3, 6 and 9 months of being raised on these foods, by macroscopic observation, histopathological observation (light microscopy), histomorphometry, and autoradiography (tracer, ³H-thymidine).
The results were as follows:
1. Macroscopic observation at 3 months or later revealed substances attached to the dental surface in some rats in both the control and experimental groups, regardless of the type of food.
2. Histopathological examination disclosed timerelated inflammatory findings only in rats given solid food in the experimental group. Exudative inflammation with infiltration mainly of polymorphonuclear leukocytes began at 2 weeks in the lamina propria of the gingiva just under the area of junctional epithelium Lymphocyte infiltration was found at 3 months, with the focus of inflammatory cell infiltration expanding toward the root apex. In the process of expansion, deepening proliferation of the epithelium over the CEJ (cementenemel junction) came to be observed, and a crevice corresponding to a gingival pocket was formed in the area of junctional epithelium and extended with time. However, there were no findings of gingivitis such as marked absorption of the alveolar bone and destruction of periodontium throughout the 9 months.
3. Histomorphometry showed a shift of the pocket bottom toward the root apex by 9 months in rats given solid food in the experimental group. Along with such changes, Oral sulcurar epithelium moved toward the root apex. In addition, while the degree of inflammatory cell infiltration just under the area of junctional epithelium increased, the number of cells composing the pocket bottom decreased.
4. Determination of the labeling index for the basal cell layer of gingival epithelium revealed that the mitotic activity of oral sulcular epithelium and in the area of junctional epithelium tended to increase with time in rats given solid food in the experimental group. In particular, the activity of the basal cells of gingival epithelium around the areas of degeneration and destruction of fibers of gingival connective tissue increased.
Thus, when rats whose bilateral large salivary glands were excised and raised on solid food, gingivitis occurred at 2 weeks, and gingival epithelium proliferated according to the degree of inflammatory cell infiltration in the lamina propria of the gingiva. It is presumed that epithelial proliferation can be a barrier against inflammatory stimulation, but may lead to deepening of gingival pocket as well.

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A dry block of human femur was decalcified by acid treatment and subjected to roentgenography by varying the X-ray projection angle. Standard dental radiographs were taken at given intervals to observe changes in the contrast and pattern of fine, rough, and network bone trabeculae. These changes in the bone trabeculae were analyzed by the RMS method (physical evaluation) and the detectability method (physiological evaluation). The abilities of these two methods to recognize the presence or absence of such changes were then compared. The difference in the representation of bone trabeculae between dental films (: Film) and dental xeroradiography (: Xero) was also investigated. With regard to changes in the contrast of bone trabeculae, the physiological evaluation method allowed easy recognition of such changes regardless of the kind of bone trabeclae, with higher detectability in Film than in Xero. Alternatively, it was difficult for the RMS method to recognize changes in fine bone trabeculae, and variations in such bone trabeculae were different in Film and in Xero. The detectability of changes in the pattern of bone trbeculae was lower than that of changes in the contrast. The detectability of fine bone trabeclae tended to be higher in Xero than in Film. It was difficult for the RMS method to recognize changes in network bone trabeculae, variations in rough bone trabeculae in Film differed from those in Xero.
The neogenesis of the bone trabecula in the pro cess of healing after extraction of a dog's mandibular molar was analyzed in the same manner as the above. The abilities of the two methods to recognize the granularity of the bone trabecula (i. e., changes in the roughness and fineness) were compared. The RMS method accurately revealed such changes in both Film and Xero. In contrast, it was found that the dectability method can recognize such changes more easily in Xero than in Film.

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The effects of prostaglandin analogues (PGE₁, E₂, D₂, I₂) on superoxide (O^-₂) production by human polymorphonuclear leukocytes (PMN) stimulated by the supernatant of a B. gingivalis 381 sonicate (BGsup) were studied in vitro by a cytochrome C reduction method.
O^-₂ production by the PMN was enhanced distinctly by the BG-sup and this increased O^-₂ production was nullified by the addition of PGE₁, E₂, or D₂ at a concentration of 0.02ug/ml. However, PGI₂, even at a concentration of 2ug/ml, could not bring down the O^-₂ production.
The amount of intracellular cyclic AMP (cAMP) of PMN treated with these PG were measured; and the results indicated all of these PG caused on elevation of the cAMP level.
The effect of dibutyryl cAMP, an analogue of cAMP, on O^-₂ production was also examined, and almost the same results were obtained as with the PG.
These results suggest that the reduction in B. gingivalis-induced O^-₂ production by PMN that occurred by addition of PG was due to the increase in intracellular cAMP; that is, cAMP appears to suppress the O^-₂ production augmented by the BG-sup.

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The purpose of this study was to evaluate antibiotics effective for periodontopathic bacteria as chemotherapeutic agents for periodontal diseases.
Antimicrobial activities of ten agents were evaluated by determinating minimal inhibitory concentrations against six periodontopathic bacterial species Bacteroides gingivalis, B. melaninogenicus ss intermedius, Fusobacterium nucleatum, Eikenella corrodens, Actinobacillus actinomycetemcomitans, Capnocytophaga species and by testing the susceptibilities to subgingival plaque bacteria.
Among antimicrobial agents tested, Minocycline (MINO), Tetracycline (TC), Penicillin G (PCG), Cefmetazole, Clindamycin (CLDM) and Metronidazole (MD) revealed strong antimicrobial activities against black-pigmented Bacteroides. In addition, MINO was also more effective against other bacterial species tested. Against subgingival plaque bacteria, MINO and PCG demonstrated strong inhibitory effect, that is 95% or more inhibition of the number of bacteria at the concectration of 1μg/ml. CLDM and TC also inhibited more than 95% of bacteria, however, MD and Chlorhexidine were less, effective at those concentrations.
From these results, MINO possessing both strong and broad antimicrobial activities against periodontopathic bacteria may be the first choice antibiotic for the treatment of periodontal diseases.

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A local delivery route of antibiotics is most desirable in periodontal disease. The purpose of the present study was to determine the most effective dosage of minocycline hydrochloride (MC) to the subgingival microflora and to determine the duration and frequency of application by means of microbiological examination.
Twenty-two patients with periodontitis were recruited for the determination of the dosage. Each patient was randomly assigned to the application of a placebo paste, 0.1, 1.0, or 3.0% MC (w/w) into periodontal pockets. A baseline microbiological examination was performed on the day of application of MC or placebo prior to the placement of the paste. The microbiological examination was repeated 2 days and 7 days following the single application of the paste.
Until 7 days, significant reductions in the density of microorganisms and in the proportion of motile rods and spirochetes were obtained only in the application 3.0% MC (w/w).
In order to determine the duration and frequency of application of MC, another experiment was performed. An additional 12 patients were assigned to either placebo application or the application of 3.0% MC (w/w). The paste was applied every 2 days for the 1st 2 weeks. Once again, a baseline microbiological examination was performed on the initial day of application. This examination was repeated at the 2nd, 4th, and 8th week after local application of the paste.
A statistically significant reduction in the density of microorganisms with the MC application was found after 4 weeks. Only after 2 weeks, the proportion of spirochetes and motile microorganisms were reduced significantly. However, the proportion of motile rods was not changed.
The most effective duration and frequency of delivery were not determined in this pilot study.
No clinical parameters were significantly improved during the study.

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The purpose of this pilot study was to establish methods for topical application of minocycline in the treatment of periodontal disease. Minocycline was used in a sustainedly released paste which was formulated to remain in periodontal pockets.
Six patients with periodontitis participated in the study. Three patients were randomly assigned to a whole mouth, one application, 3.0% (w/w) minocycline paste treatment group and three patients were assigned, using a split mouth design, to one application of 3.0% (w/w) minocycline paste, placebo paste, or no paste.
The minocycline only group of three patients had baseline microbiological examinations prior to application of the paste. After seven days the examination was repeated. The density of microorganisms and the population of motile microorganisms were significantly reduced compared to the baseline. This reduction seems more prominent than the reduction found after application of a water soluble paste previously reported.
The other three patients received a scaling procedure two weeks prior to the application of the experimental paste. A baseline microbiological examination was performed prior to scaling. Additional examinations were performed two weeks after scaling, one week after paste application, and two weeks after paste application. Two weeks after scaling the density of subgingival plaque bacteria were significantly reduced. However, the population of motile microorganisms showed no significant change. A week after paste application, the sites where minocycline was applied demonstrated a significant reduction in both the density of microorganisms and the population of motile microorganisms. Two weeks after application, density of microorganisms and population of motile microorganisms increased to the same levels as before application, but still reduced in comparison with those before scaling.
The results of this study suggest the possible benefit of the local, sustained delivery of minocycline to periodontal pocket.

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Early-onset periodontitis has been implicated from the perspective of a host-parasite interaction. This case report describes microbiological examinations and the assessment of host defence functions which were performed on a mother and daughter both of whom had early-onset periodontitis.
The mother's diagnosis was rapidly progressive periodontitis. She had severe gingival inflammation and progressive bone destraction. The daughter's diagnosis was localized juvenile periodontitis. She had little gingival inflammation, but presented with progressive bone resorption.
Microbiological examinations revealed an elevated proportion of rods and spirochetes from the mother's affected sites. Fewer spirochetes were found in the daughter's affected sites. Fusobacterium sp. were the predominant microorganisms in the plaque of both the mother and the daughter. Actinobacillus actinomycetemcomitans was not detected in the subgingival plaque of either the mother or the daughter.
Humoral immune responces both in mother and daughter were much higher to F. nucleatum B. gingialis, and A. actinomycetemcomitans than any other periodontally related microorganisms examined. Peripheral neutrophil functions were also studied. These studies demonstrated that the mother had a depressive neutrophil phagocytosis. The neutrophil studies performed for the daughter revealed a depressed function not only in neutrophil phagocytosis but also in neutrophil chemotaxis.
From the perspective of host-parasite interaction, we propose that the disease status of the mother and the daughter are very similar. We believe the disease process in both the mother and the daughter strongly suggests an identical mechanism.

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The effect of the pretreatment of Bacteroides gingivalis with serum agglutinin on the B. gingivalisinduced superoxide anion (O₂^-) generation by mouse polymorphonuclear leukocytes (PMN) was studied. A serum of a Chediak-Higashi syndrome patient with severe periodontitis involvement contained eight fold agglutinating activity against B. gingivalis of agematched control. B. gingivalis induced by itself the 2- generation by PMN appreciably. The heat-in-O activated patient's serum, IgG fraction of Sepharose CL-6B fractionation and purified IgG sensitized B. gingivalis to augment the O₂^- generation by PMN. However, IgM fraction of patient's serum containing agglutinating activity against B. gingivalis did not.
These results demonstrated that the IgG class but not the IgM class of antibody reactive with B. gingivalis stimulated O₂^- generation by PMN when bound on the surface of B. gingivalis. The role of antibody reactive with B. gingivalis in the pathogenesis of this microorganism was discussed.

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Superoxide dismutase (SOD) produced by Bacteroides gingivalis may be one of virulence factors that permit this periodontopathic bacteria to survive in periodontal pocket. This study deals with the purification and some properties of SOD from B. gingivalis 381 cells. The SOD was purified from crude cellextract by ammonium sulfate treatment, followed by Phenyl-Sepharose CL-4B hydrophobic chromatography, Q-Sepharose ion-exchange chromatography and SuderRose 12 gel filtration. The molecular weight of the purified enzyme was estimated to be 46, 000 by Fast Protein Liquid Chromatography System using SuperRose 12 column, and SDS-polyacrylamide gel analysis revealed that this enzyme consisted of two equal size subunits whose molecular weight was 23, 000. Three isoenzymes were visible on native polyacrylamide gel used the purified enzyme as a sample. Optical spectrum of the purified enzyme indicated two absorption maxima at 280 nm and 350nm, suggesting that this enzyme would be Fe-SOD.

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The aim of this study was to evaluate the bactericidal effect of polymorphonuclear leukocytes (PMN). For this purpose, we investigated the superoxide anion (O₂^-) production of PMN obtained from peripheral blood, or gingival crevicular fluid. Furthermore, we examined the myeloperoxidase (MPO) activity of PMN.
The results obtained were as follows.
1. There were the superoxide anion (O₂^-) release of PMN obtained from peripheral blood, or gingival crevicular fluid, when these cells were stimulated by anaerobic bacteria.
2. Actinobacillus actinomycetemcomitans, or Bacteroides gingivalis, Capnocytophaga could strongly stimulate PMN to release a large amount of O₂^-.
3. Both live cells and dead cells of Bacteroides gingivalis could stimulate PMN to release a large amount of O₂^-, but there was a decline of O₂^- release, when these cells were heated at over 80°C
4. In some patient, MPO activity of PMN obtained from inflamed gingival crevicular fluid was lower than that of PMN obtained from peripheral blood. These results indicated that a large amount of O₂^-release was occurred at the gingival area of the patients with periodontal disease. However, in some patient, there was the reduction of MPO activity which was important enzyme to produce the powerful bactericidal oxygen radicals.

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To clarify the mechanism of bone resorption by osteoclasts or macrophages, the bone resorption assay using ⁴⁵Ca-labeled rat calvaria or killed bone is usually used. However, it is difficult to determine the effector cell that resorbs the bone because of the variety of bone cell types (osteocytes, etc.), cytokines and collagen present in the assay system. So we introduced a simple bone resorption assay system which uses hydroxyapatite (HA), the main mineral component of bone and purified human monocytes. And we have reported that human monocytes destroyed ⁴⁵Ca-labeled synthetic hydroxyapatite (⁴⁵Ca-HA) and this activity was enhanced by addition of the cultured supernate of PHA stimulated human peripheral leukocytes (PHA-sup).
In this paper, the mechanism of bone-mineral destruction (⁴⁵Ca release from ⁴⁵Ca-HA) by human monocytes was investigated.
The results were as follows:
1. Monocytes adhering to HA were observed by lightmicroscopy and electronmicroscopy in 48 hr culture.
2. By addition of PHA-sup, monocytes-adhering activity to HA was enhanced significantly and the quantity of released ⁴⁵Ca from ⁴⁵Ca-HA by monocytes was increased.
3. By addition of cytochalasin B (1μg/ml-10μg/ ml), the quantity of released ⁴⁵Ca from ⁴⁵Ca-HA was decreased dependently to the concentration.
4. Released ⁴⁵Ca in media from ⁴⁵Ca-HA was detected in 24 hr culture, but cell-intral ⁴⁵Ca was detected in 96 hr culture.
These results suggest that bone-mineral destruction by monocytes is related to the concentration of citric acid in the micro-environment of the adherence site.

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Distribution of γ-carboxyglutamic acid (Gla) in rat mandibula was examined using high-performance liquid chromatography. Rat mandibula was divided into three portions: incisor, molar and ramus.
Gla could be detected in all bone samples. Both in 4 and 8 weeks-old rat, high Gla content was found in incisor-portion as compared with other two portions (1.7-2.8 fold). There was no difference in Gla contents between molar-and ramus-portions.
Since the incisal alveolar bone has been indicated to show an active bone metabolism, the distribution of Gla content in this system may reflect the characteristics of alveolar bone remodeling.

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The aim of this study was to investigate the histopathological changes of alveolar bone regenerated among hydroxyapatite blocks (HAP) which were used as bone graft material.
Previous to implantation, both sides of P₂ and P₄ in two beagle dogs were extracted. Three months after extraction, artificial bone defects were prepared at the mesial sites of P₃ and M₁. HAP were implanted into the mesial sites of M₁ and not into those of P₃ as control. On six and twelve months after implantation, the animals were killed and their mandibles were biopsied for light microscopic study.
The results obtained were as follows.
The external forms of the regenerated alveolar bone of controls showed hallows at mesio-distal center of bone defects, but those of experimental sites were similar to anatomical feature. Harversian systems and osteocytes existed in the regenerated bone tissues among HAP. On twelve months after implantation, red parts stained by Azan staining which suggested mature bone, increased in the regenrarated bone tissues and fatty marrows had appeared. A part of bone marrow showed irregular feature and collagen bundles attached to irregular bone surface.
Concluding above-described results, the height of the regenerated alveolar bone in experimental sites had been kept for twelve months. Further those bone tissues presented the similarity of maturation process and inner remodeling in control sites.

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The present series of studies was carried out in order to test the application of a TCP grafting material, Synthograft ®, to periodontal treatment and to evaluate its clinical usefulness. This paper reports the results of studies on a probable relationship between the rate of bone filling one year after bone grafting and the prognosis of the graft. The subjects were 15 patients with 19 bone defects who visited Kanagawa Dental College Hospital. After initial preparation, a flap operation was performed, and Synthograft ® was implanted into the bone defect. The pocket depth, attachment level and mobility were determined before surgery and at 3, 6 and 12 months after surgery. Roentgenography was also performed at one week and 1, 3, 6 and 12 months postoperatively, for observation and determination of the rate of bone filling. The results revealed a postoperative increase in clinical attachment gain in patients who had high rates of bone filling. In addition, the presence of radiolucency was noted in the marginal area between the site of the graft and the root in many of the patients with high rates of bone filling. The above findings suggest that when Synthograft ® is used for implantation, care should be taken to facilitate postoperative stability and to prevent postoperative outflow of the grafting material.

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The present investigation was performed to assess the efficacy of a initial, nonsurgical periodontal treatment (hygienic phase) in adults with malocclusion .
Eleven patients took part in this study. Scaling, root planing and instruction in oral hygiene were completed before orthodontic treatment. During the orthodontic treatment, patients were rechecked every two weeks and given active periodontal maintenance care.
As a result of nonsurgical periodontal treatment, the Gingival Index scores, probing depth, plaque score, Gingival Bleeding Index and tooth mobility were markedly reduced. While the width of keratinized gingiva was slightly reduced, no difference could be seen in the width of attached gingiva.
This study has demonstrated that the clinical severity of periodontitis is reduced significantly during the course of fixed appliance therapy, provided careful initial, nonsurgical periodontal treatment (hygienic phase) of the existing periodontal inflammation is given.

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This study was performed to know the relationship between bone loss and root surface area. Sixty upper and lower anterior teeth which had been previously extracted because of periodontal disease were used. Root surface was divided into two areas such as the exposed root surface and the other root surface covered with periodontium. Then the total root surface area, exposed root surface area and the other root surface area were measured by divisional planimetry method. The relationship between pocket depth and loss of epithelial attachment level was investigated also.
The means of each total root surface were as follows: upper central incisor: 176.0mm², upper latelal incisor: 172.8mm², upper caine: 218.5mm², lower central incisor: 134.8mm², lower latelal incisor: 178.8mm², lower canine: 211.6mm². The rates of the areas of the root surface covered with periodontium were as follows: upper central incisor: 24.0%, upper latelal incisor: 24.9%, upper canine: 6.9%, lower central incisor: 27.2%, lower latelal incisor: 18.8%, lower canine: 18.2%.
It was observed that pocket depth was more deeper in mesial and distal tooth sides, and the largest loss of epithelial attachment level was observed in labial and palatal tooth sides. The rates of loss of epithelial attchment level of the extracted teeth were approximately 80% of the total root surface area except upper canine.

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The aim of this report was to find a way leading to WHO's CPITN from the morphological point of view.
Materials and methods were as follows. For the gingiva of monkeys, additional lines was attached to the probe of CPITN and a measure cord of the probe was reconstructed. A certain gingival area of cynomolgus monkeys was measured with this instrument, whose results were classified in the code order. At the same time, the specimens were prepared for light and electron microscopic examination.
The results showed that the histological changes formed a link in the code order. Whereas the change became sometimes out of order, one corresponding to the later code appearing earlier.
From these facts, a futher survey of CPITN code may be desirable, taking into consideration of the following points.
1. One item (bleeding, calculus, depth of gingival pocket) must be analyzed under each code, i. e. each item is not referred to a certain code but distributed to every code, under which item must be estimated.
2. One for epidemiology and the other for treatment needs should be prepared separately.
3, Special diseases and clinical cases (hypertrophy, bone disease, etc.) must be considered.

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The purpose of the present investigation was to examine the oral conditions in severe (SG) and moderate (MG) groups of 200 mentally retarded persons from 16 to 56 years of age. SG consisted of 50 male and 50 female patients with immeasurable or low IQ, and mental disorder such as Down's syndrome, epilepsy brain edema and others. Almost all the patients in SG had no habits of mechanical mouth cleaning, and no previous dental treatment other than teeth extractions to relieve pain in a few cases. MG also consisted of 50 male and 50 female patients with mental retardation and IQ up to 80. About one half of the persons in MG had habits of tooth brushing and previous dental history. Examination was made on the prevalence and severity of periodontal disease and dental caries. The observations gave the following results.
1. The inflammatory changes of the gingiva were more severe in SG than in MG, and especially in the female groups. The prevalence and severity of inflammation were affected more by group difference than sex.
2. The bone resorption at the lower incisal regions was remarkable in the female than male, and especially in SG. The correlation between bone resorption rate and age was statistically obtained in male of SG (p<0.05), and it was thought that the height of the alveolar bone gradually decreased with advancing age in man without mechanical mouth cleaning.
3. Tooth mobility was severe in both the female groups, and showed possible reflection to gingival inflammation and bone resorption.
4. There was no significant difference in the occurence of caries free teeth between two groups.
5. As to caries attacks, there was no apparent prevalence due to sex difference, but was high in severity in SG, . However, in MG there was no sex difference in severity, but was high in prevalence. The upper and lower first molars were significantly involved, and the canine and lower incisors were less in both the SG and MG groups.

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The purpose of this study was to evaluate if the ultrasonography would be applied to the examination of gingival form. The gingival thickness of a dog measured with using the ultrasonography and penetrating gingiva by the needle was almost same value.
The ultrasonograms of gingival cleft with vertically and horizontally scanning could visualize the gingival form. Then, this equipment could be useful in examination of gingival form.

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The purpose of this study (Report 2) was to investigate the effects of the difference of length of tooth brush bristles and that of row of tufts on toothbrushing pressure and plaque removal in Scrubbing method.
Nine kinds of toothbrushes which were different in lengths of toothbrushes (8mm, 10mm, 14mm) and in rows of tufts (2 rows, 3 rows, 4 rows) respectively were used in this study. Referring to the results of the first report, the bristles were designed to be rounded ends, and 0.25mm in diameter. Nine subjects participated in this experiment. Plaque scores were measured before toothbrushing and after toothbrushing, and the plaque removal rates were calculated. The toothbrushing pressures were determinded by Watanabe's method.
The results were as follows: Toothbrushes with bristles of longer length showed significantly more smaller brushing pressure and those of shorter length showed significantly more higher plaque removal. Statically significant difference could not be found among the three different rows of tufts in brushing pressure and plaque removal. The toothbrushes with bristles of 10mm long three of rows of tufts showed the highest effectiveness on plaque removal.

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The synchronous recording system with masticatory muscle activity, initial occlusal contact and jaw movements was constructed and its charactaristic was discussed.
Electrical signals were induced with bipolar surface electrodes on the skin overlying the masseter muscle, with microvibration pick up on the forehead at the initial occlusal contact and with mandibular kinegio graph during jaw movements.
Each electrical signal was recorded synchronously on the data recorder.
Recording speed of the data recorder was used 19.5 cm/sec and two different replayed speeds (19.5cm/sec and 2.38cm/sec) were selected for analyzing the data.
The recording paper was moved at a speed of 2, 5 or25mm/sec.
Address index (recorded and replayed at a tape speed of 19.5cm/sec and written at a paper speed of 2mm/sec) was made an entry in the recording paper with number of the tape counter.
When high replayed speed and slow paper speed were selected, whole experimental period of datum was able to observed.
When slow replayed speed and high paper speed were selected, fine phenomena of muscle activity, tooth contact, jaw movements, silent period and tooth contact sliding time etc. were able to be observed.
This synchronous recording system was able to employ for analyzing the relation of muscle activity, initialocclusal contact and jaw movements.

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Removal of supra and subgingival plaque and calclus is the most important factor in periodontal therapy. In practice, however, deeper the pocket is, the harder is to make the instrumental approach with hand or conventional ultrasonic scaler due to the registance of the soft tissue wall of the pocket.
Periodontal probe is readily accessible to the bottom of the pocket with slight patient's discomfort without local anesthesia. We designed probe-typed tip for ultrasonic scaler (OSADA ENAC-3) capable of being used for debridement in the deep pocket.
To examine the functional potential of the device, in vitro and in vivo experiments were undertaken in the present study. In the first experiment effect of the tip on removing 170 calculi spots on extracted teeth roots was evaluated. The second was carried out on 46 root surfaces of 30 teeth scheduled for extraction due to advanced periodontal disease. To examine the accessibility of the tip to the bottom of the pockt, its ability to remove the plaque and calculus and patient's discomfort during the procedure, ultrasonic debridement with the tip was done in linear fassion along the long-axis of selected tooth surface to the bottom of the pocket. The tooth was extracted and stained with 1% methylene blue. The depth of pocket and ultrasonic debridement area were measured under stereo-microscope. Furthermore, the patient's discomfort while debridement procedure with the tip was also evaluated.
Following results were obtained.
1. The device could efficiently remove all the calculi spots on extracted teeth in vitro study.
2. Accessibility and plaque and calculus removability of the tip was good in patients with less than 9 mm depth pocket.
3. In pockets over apical curved roots, acces-sibility for debridement was hard to accomplish.
4. While ultrasonic debridement, 69.2% of the patients did not complain of discomfort, 28.2% claimed slight discomfort and only 2.6% needed local anesthesia who had hypersensitivity against probing before ultrasonic debridement.

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experimental stain removal and roughness of the metallic plate would be affected by the brush using in handpiece with three different pastes, ultrasonic scaler and hand scaler instrumentation, quantitative measurement and morphological observation were made.
The results obtained were as follows:
1. On the stain removal, the largest effect was obtained in the using the brush, followed by ultrasonic scaler and hand scaler.
2. On the roughness of the metallic plate, the largest defect was observed in using hand scaler, followed by ultrasonic scaler and the brush.
3. Vertical and horizontal stripes of defects under the brush, rippling wave defects under ultrasonic scaler and straight stripes of defects under hand scaler were observed on the scanning electron microscope.

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The oral cavity is influenced by physical, chemical and biological irritants as can be seen in the case of infection followig the extraction of a tooth. Medicaments applied to the oral mucosa are often rapidly carried away by salivation, mastication and drinking, thus interfering with their intended effect.
Because of conditions in the oral cavity, it is necessary for medicament to remain in contact with the wound and the operated area which should be isolated from external irritants. The film type material SI-3906 having new components and adhesion capacity was developed to compensate for these problems in applying medicaments to the oral mucosa.
Clinical trials produced the following results.
1. SI-3906 remained on the affected and operated area for an average of over 4 hours.
2. Owing to the time it remained in place, it could potentially be used in conjunction with slowacting medicaments.
3. It could potentially isolate the effected area from direct irritants.
4. It prevented suture threads from becoming incorporated into the periodontal pack, making it appropriate for application following surgery.
5. No harmful side effects were observed.

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In the present investigation, Dexaltin® ointment was applied to gingival lesions for the treatment of chronic desquamative gingivitis.
Dexaltine® is a steroidal ointment for the oral cavity ontaining 0.1% desamethasone included polyacrylic acid natrium as a constituent of the base. Polyacrylic acid natrium has the fine property of adhering to the oral mucosa, making it easy to apply to patients and stable to thermal changes and microorganisms. Dexaltin® has been used for other oral diseases and its efficacy has been established.
In this investigation, Dexaltin® was used for 2 patients who were diagnosed as having chronic desquamative gingivitis. The clinical findings indicated some beneficial effects which were not shown by the usual steroidal ointments for the oral cavity.

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