Clinically normal gingivae were taken from adult human (male and female, aged 20 to 54-year old) for the electron microscopic specimen, and were treated to fixing and embedding with routine methods.
In spite of clinical feature, microscepic observation showed inflammatory changes, and there were some differences between specimens in degree of inflammation. Fifteen specimens were emploied accordinng to the following conditions.
a) the gingival sulcus less than 1 mm depth.
b) the inflammatory changes (such as inflammatory cell infiltration and dilatation of capillaries) located within underlying connective tissues.
Fifteen specimen were cut with ultramicrotome, and observed electron microscopically.
The results were as follows:
A) On the enamel surface located at the coronal part of sulcus, a few epithelial cells, which had a electron lucent layer and hemi-desmosomes between cuticle and those cell membranes, were observed.
B) Toward the apical end of epithelial attachment, cuticle decreased gradually in width and disappeared finally.
C) It was observed in four cases of fifteen specimens that cuticles formed irregular figure, showing particular convex and concave figure.
D) The most apical end of epithelial attachment was made of one or several cell layers. The epithelial cell located at the most apical end had a cellular projection toward apical direction on the cemental surface.
The cellular projection was noticed in the several cells located coronally adjacent to the most apical cell.
E) On the cell membrane of the most apical epithelial cell, there were observed two fine structures. One was a structure of the epithelial attachment between the epithelial cell and the cemental surface, having an electron lucent layer and hemi-desmosomes. The other was a structure of the basement membrane between the epithelial cell and connective tissue, having lamina lucida, lamina densa and hemi-desmosomes. In some cases it was confirmed that these two fine structures were coalescent on the apical surface of the cell membrane.
F) From the cemental surface located more apically, some collagen fibers run into connective tissue, forming irregular arrangement. Some cases of cemental surface were denuded without anchoring the collagen fiber. There were some differences between specimes in the degree of irregularity, but the collagen fivers arranged regularly from the surface of cementum at a distance of 300 microns away from the apical epithelial cell.
From those results, author discussed about the origin of cuticle and the process of epithelial cell migration in the apical direction in early stage of inflammed gingiva.

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Guinea pigs were substantially sensitized to the low molecular weight chemical dinitrochlorobenzene (DNCB), by the injection of the adjuvant materials examined into a skin site primed 4 days previously with a borderline sensitizing concentration of DNCB.
The adjuvant materials used were Freund's complete adjuvant (FCA) as positive control, Freund's incomplete adjuvant (FIA) as negative control and FIA containing oral bacteria (5mg/ml) as experimental group.
Oral bacteria was Actinomyces ATCC 15987, Streptococcus mutans Ingbrid, Bacteroides melaninogenicus 32-2, Veillonella alcalescens ATCC 17745 and Fusobacterium fusiforme HT-40.
The adjuvant effect was evaluated by the skin reaction at day-6 challenge testing. Challenge produced strong delayed type reactions in FCA treated animals. FIA was inefficient. As for oral bacteria, actinomyces was effective as much as FCA, bacteroides and streptococcus effective, and veillonella and fusobacterium less effective.

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With reference to a dextranase preparation obtained from a strain of Spicaria species, our previous reports have described the in vitro effects on different polysaccharides prodused by oral streptococci and the in vivo effects on human dental plaque.
The aim of this study was to clarlify the in vitro effects of this dextranase on polysaccharide prepared from human dental plaque.
The hydrolyzing effect of the dextranase on the polysaccharide from human dental plaque was estimated by calculating the increase of reducing groups. When one mg of the polysaccharide dry weight was exposed to the dextranase containing 0.25, 1.5, 25 and 250 units for 18 hours, about 4, 5, 7 and 12 per cents of total glucose in the polysaccharide were hydrolyzed, respectively. In the reaction time of 30 min, however, the dextranase exhibited only feeble hydrlyzing effects against these.

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A Plaster disk was implanted in rabbit's femoral muscles and X-ray was taken immediately and 5 days later to be analyzed with photo-pattern-analyzer.
The results obtained were as follows.
1) Absoption of plaster disk developed from the middle to the center of the plaster disk.
2) Radiographic absorption was observed in 20 days and 55 days in one rabbit each, and 45 days in four rabbits.
It seemed that plaster disk destroyed into fragments in one rabbit resulted in the earlist absorption.
3) On an isodensity analysis, the density of the plaster disk began to disappear on 15th day and 30th day in one rabbit each, and on the 25th day in four rabbits, after implantation.

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Color Data System is suited for radio-graphical film reading as well as converting optical data in the form of opaque or tratransparent graphs, into a digital format suitable for digital processing. This study comparision of normal alveolar bone and advanced periodontal alveolar bone.
In summary, we have found that the Color Data System has given us useful information about virtually every type of periodontal destruction appearing in the standardized radiographs.
A application of the technique is described which should result in increased sensitivity and accuracy. It is believed that additional clinical studies, now in progress, will confirm this technique.

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The purpose of this experiment was to evaluate the observation on wound healing, capillary outgrowth and vascularization of free autogenous gingival grafts and pedicle flaps in dog.
The histologic examination was performed on 7 adult dogs. The surgical procedure was performed under general anesthesia administered intravenously, utilizing pentobarbital sodium (25mg/cc solution per kilogram of animal weight.). Surgical procedure is done in labial gingiva of mandibular and maxillar anterior teeth. Preparation of the recipient site were sharply dissected down to the periosteum. After preparating the recipient site, a gause moistened with NaCl solution is placed over the bed (wound area) to control bleeding.
The grafts tissue was excised with Bard-Parker blade (#12, #15). and the grafts was placed on the previously prepared recipient bed and stabilized with a suture in each corner.
Following surgical intervention, each dog are sacrificed at the next periods, 0 day, 1 day, 3 days, 7 days, 14 days 21 days, 28 days.
The dogs are injected through the carotid arteries with a 25 percent aqueous solution of indian ink (or with a 8 percent chloroform solution of gutta percha). A pressure averaging about 200mmHg was employed using a hand-operated injection syringe (in a25 percent a aqueous solution of indian ink) or a pressure averageing about 350mmHg was employed using a hand-operated injection syringe (in a 8 percent chloroform solution of gutta percha). Fixing by Formalin: Alchohol (1:1) and decalcified by 5 percent trichlor acetic acid.
The result indicated that free gingival grafts were found to heal more slowly than the pedicle flaps., and the epithelium of free gingival grafts exfoliated and injured in a great extent.
The results of microscopic findings demonstrated the healing and revascularization of free gingival grafts and pedicle flaps.

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The purpose of this study was to observe the clinical appearance of the healing and increased zone of attached gingiva of free gingival grafts and pedicle flaps. Nineteen patients were used to examine.
The results indicated that the healing and increased zone of attached gingiva of free gingival grafts and pedicle flaps are similar, but free gingival grafts were found to heal more slowly than the pedicle flaps. A clinical findings revealed that free gingival grafts and pedicle flaps covered a denuded root and increased theattached gingiva.

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The relationships between the crowding and the gingivitis were studied on 147 malposed anterior teeth of 26 orthodontic patients (4 males and 22 females, 11-29 years of age) and 161 malposed anterior teeth of 29 male students (22-25 years of age).
1. Positive correlations were found between the degree of displacement of tooth and the degree of the gingival inflammation in both patients and students.
2. The change of gingival inflammation due to the improvement of occlusion by orthodontic procedures were observed in the patients.
In conclusion, the greater the displacement of tooth before orthodontic treatment, the gteater the improvement of gingival inflammation was obtained by orthodontic treatment. However, in the case of severe gingivitis, less improvement of inflammation was observed.

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On 870 teeth, the width of attached gingiva was measured, Using Bower's method. Average width of each maxillaly tooth in normal gingival group (gingival sulcus was within 1.5mm), was ranging from 0.8 to 4.8mm. Average width of maxillaly both central incisors, premolars, and second molars, was 2.9mm, 2.4mm, and 4.6mm respectively.
Average width of mandibular both central incisors, premolars, and second molars was 3.0mm, 1.1mm, and 2.0mm respectively.
Average width of each maxillaly tooth with periodontal disease was measured 3.2mm in central incisors, 1.8mm in first premolars and 3.5mm in second molars.
Average width of mandibular central both incisors, premolars and second molars, was 2.9mm, 0.7mm, and 0.9mm respectively.

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