The cranio-facial morphology of 282 male young adults was studied in relation to the dental arch types which were concurrently measured on the plaster models taken from the same subjects, and the possible correlation between these two values was discussed. 1) The most frequent found of the cranio-facial types wes the brachymorphic type in term of the morphologi cal classification of facial index, the ovoid or round type in term of the authors diagrams based on his measurement. 2) In the measurement of dental arch, the angle BDB' and the value of ratio AE : AC were calculated and the correlation between these values were studied. The result obtained seems to demonstrate clearly the morphological characteristics of the dental arch as shown in Fig. 7 and in Table 6. 3) No clear conclusion has been reached as to the correlation between the cranio-facial and dental arch morphologies.

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Hereditary traits in the head, face and mouth of parents and children were studied as to the resemblance, the average percent deviation, the correlation coefficient together with effects of environment upon the hereditary manifestations. The results obtained were summarized as follows. 1 Incisors : Resemblance in the incisal occlusion type was more clearly demonstrated between father and son (F : S) than between mother and daughter (M : D). As to resemblance in the incisal overbite, however, no remarkable difference was found between every combinations of parents and children. 2 Length and width of dental arch : Hereditary influence was more conspicuous between M : D and between father and daughter (F : D) than between mother and son (M : S) and F : S. 3 Dental arch index : Difference in resemblance was small between each combinations. 4 Length of dental arch ; Resemblance was more conspicuous between father and children (F : C) than between mother and children (M : C). 5 Palate height ; Resemblance between parents and children was more conspicuous in the posterior palatal height than in the anterior one, which was more distinct between M : C than between F : C. Other hereditary traits in this region behaved likewise. 6 Palatal height index ; Resemblance between M : S and F : S was stronger than between F : D and M : D. 7 Median palatine suture ; Hereditary effect on the length was more clearly demonstrated in between F : C than in between M : C. Resemblance in the suture forms was stronger in between F : S and M : S than in between F : D and M : D. 8 Palatal arch ; Hereditary influence on the height was stronger in between M : C than in between F : C. Resemblance of palatal arch types was stronger in between F : S and M : D than in between F : D and M : S. 9 Number of Plicae palatinae transversae ; Resemblance between M : C was stronger than between F : C. 10 Dental arch types ; Resemblance was stronger between F : S and M : D than between F : D and M : S. 11 Circular length of dental arch ; Hereditary influence was greater between F : D and M : D than between F : S and M : S. 12 Breadth of incisor crown ; Resemblance was stronger between F : D and M : D than between F : D and M : D than between F : S and M : D. 13 Number of lower molar cusps ; No remarkable difference in resemblance was found between each combination. 14 Dislocated tooth ; Separated median line ; Resemblance between F : S and M : D was slightly stronger than between F : D and M : S. 15 Torsioned tooth ; Conical tooth ; Dwarf tooth ; Geminated tooth ; Carabelli's cusp : Prostostylid ; No remarkable difference was present between each combination. 16 Incisor occlusion types ; Resemblance between F : S and M : D was slightly stronger than between F : D and M : S. 17 Cranio-facial region ; Resemblance between F : S and M : D was stronger than between F : D and M : S. 18 Lips ; Resemblance between F : D and M : D was slightly stronger than between F : S and M : S. 19 Hair types ; Difference in resemblance was not found between each combination. 20 Number of eye lids ; Resemblance between F : S and M : D was slightly stronger than between F : D and M ; S. 21 Number and position of whirl of head hair ; Resemblance between F : D and M : D was slightly stronger than between F : S and M : S. 22 Position of thumbs when right and left hands were clasped ; Resemblance between F : S and M : S was slightly stronger than between F : D and M : D. 23 These rememblances between parents and children in cranio-facial region, lips, dental arch, palate and teeth did not occur uniformly, i.e, some traits resembled between same sex combinations while other traits resembled between different sex combinations. The effects of heredity and environment exerted upon these traits were not also simple. Resemblance between parent and children wes weaker than resemblance between twins.

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The emulsified solution of Folidol E-605 was given subcutaneously on the back skin of 51 albino rats in amount ranging from 1.0 to 6.0mg pro kilogram body weight thereby to induce either the chronic, subacute or acute poisoning in proportion to the doses given. The changes of the tooth and the surrounding tissues from the first day to the sixth month of the administration were consecutively followed up patho-histologically and the results were summarized as follows. 1) The body weight either reduced or slightly increased in the subacute poisoned groop, while in the chronic poisoned groop given 3mg of Folidol the body weight first reduced, then increased steadily. 2) The pathologic changes similar to those induced in the internal organs of the acute poisoned animals were also observed occurring in the chronic poisoned animals. 3) Of the histological findings in the tooth and the surrounding tissues, the-following changes are to be noted. a) Between the formative layer of ameloblasts and the young enamel substance insoluble in the solution of acids one noticed drop-like, granular or cuboidal foreign materials deposited. No changes, however, were seen in the tooth enamel. b) Only in the subacute and chronic poisoned groops were found the pathologic changes in the ameloblast layer. In the layer from its formative end to the region dissolved by the acids, the inner structure of cells was either irregularly oriented or even disintegrated. The outer ameloblast layer undergoing atrophy lost its pectinated epithelial papillae. and the concaved portions lying between the papillae showed vacuolar degeneration. In some specimens hypertrophy of the epithelial papillae took place, resulting disapperance of the concaved portions. In the intermediate layer of the ameloblast at the gingival margin of alveolar process, vacuolar degeneration and cyst formation were observed. c) Blood congestion and bleedings of irregular dimensions occurred in the pulp tissue, especially in those of the molar teeth. In the severe cases of the poisoning the pulp assumed edematous appearance accompanying atrophy of the ground cells. Further there occurred decreased staining reaction of the odontoblast, atrophy of the cell nuclei, irregular arrangement of the odontblast layer and its vacuolar degeneration. In the pulp of molar teeth parts of the cells underwent nucleus disintegration and finally their disappearance. In the dentin a slight disturbance in calcification, showing itself like the stratus, was observed, which was more frequent in the dentin of molar teeth. d) The pathological changes in the tooth sac and the periodontal membrane occurred exclusively in the incisors, showing congestion as well as edematous loosenning of the connective tissue surrounding blood vessels in the membrane. e) Otherwise there were found in the enamal, gingiva and alveolar bone no remarkable changes whatever. 4) It was concluded from our results that Parathion seemed to exercise moderate effects on the embryo and suckling of the animal by way of the placenta and breast feeding. It was demonstrated that the similar moderate degeneration affecting the mother animals under the poisoning occurred to the offsprings in the kidney, liver as well as in certain regions of the salivary glands. These, however, were not found in the tooth and the surrounding tissues.

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In the normal of 30 to 49 and 50 to 60 years old the circular type of the Papilla incisiva was prevalent and in all the other subject groups the spindle type prevailed. The occurrence of the types other than the circular and spindle types were irregular throughout every subject groups examined. Of the grade of the development of the Papilla incisiva the perfect type occupied more than half of the entire subjects. Generally the perfect type was found markedly frequently at about 20 years of age while a tendency of slight degeneration of the type was found in the old age. About the shape of the Papilla incisiva Mitsui stated that in the boys 10 to 12 years old the spindle type occurred in 44.4 per cent, the bud type in 28.9 per cent, the spear-head type in 14.4 per cent, the elliptic in 7.8 per cent, the triangle in 2.2 per cent and the circular in 2.2 per cent ; Sato stated that in men 20 to 49 years old the pear type occurred in 39.5 per cent, the oval in 18.2 per cent, the circular in 8 per cent, the elliptic in 23.1 per cent and the rod type in 10.5 per cent. Murakami stated that the spindle type was prevalent and Maruyama the elliptic (38.46 per cent). Mitsui stated that in men the spindle type occurred in 27.30 per cent, the spear-head type in 21.36 per cent and the elliptic in 8.93 per cent. The frequencies of the spindle and the spear-head type of the Papilla incisiva by the author's data in the normal 10 to 12 years old were about the same with Mitsui's data for the subjects 10 to 12 years old. The occurrence of the circular and the elliptic was slightly more in the author's data than in Mitsui's. The frequencies of the elliptic and the circular of the Papilla incisiva by the author's data in the normal 22 to 24 years old were nearly the same with Sato's data for the subjects 20 to 49 years old. The frequency of the oval was slightly more in Sato's data than in the author's. The frequency of the elliptic by the author's data in the normal 30 to 49 years old and that in the prisoner were nearly the same with Sato's data for the subjects 20 to 49 years old. The frequency of the spindle type by the author's data in the normal 22 to 24 years old was slightly less than Mitsui's data for the adult and in the normal 30 to 49 and 50 to 60 years old the frequency was nearly the same with Mitsui's data for the adult. The frequency of the spear-head type in the normal 22 to 24 and 30 to 49 years old were less than Mitsui's data for the adult, and the frequency of the elliptic was larger than Mitsui's. Thus the spindle type prevailed in every subject group in agreement with Murakami's report, but divergent from Maruyama's report in which the elliptic occupied 38.46 per cent. In relation to the age changes of the Papilla incisiva Sato stated that its form changed with increasing age from the pear type to the circular or the oval ; Mitsui stated that the spear-head type prevailed in the embryo period, the saddle type in the boyhood and in the adult and the circular in the aged. According to the author's observation, the occurrence of each type of the Papilla incisiva was irregular throughout every age groups of the subjects except that in the normal 7 to 20 years old the spindle type prevails and in the normal 30 to 49 and 50 to 60 years old the circular type becomes prevalent progressively with age. Sato classified the developmental grade of the Papilla incisiva into "superior, " "medium, " "inferior" and "trace, " and he reported on the Japanese that from 5 to 14 years old the "inferior" grade occupied 47.6 per cent of the sudjects ; from 15 years on, however, it increased development and in the subject 20 to 30 years old the "medium" development comes to occupy 46.3 per cent and also the "superior" devevelopment

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By dental examination of workers engaged in heavy muscular labor and exposed to high temperature it is observed that they are frequently (58%) suffering from gingival atrophy. It occurs ususually at the gum margin on the palatal side of the first or second molar teeth of the upper jaw, rarely also on the lower jaw. Occasionally the second premolar teeth are attacked. It resembles the senile or juvcnile atrophy of the gingival margin, and is most conspicuous at the central part of toothneck. Other workers engaged in heavy muscular labor but not exposed to high temperatureand those engaged in light labor show also the similar sign of atrophy, but less frequently, 46% and 12% respectively. The morbidity rate of caries is practically the same among the three kinds of laborers (79-85%). But gingivitis, teeth calculus and alveolar pyorrhea are more frequent among the heavy workers exposed to high temperature than among the light workers. What is the etiology of this gingival atrophy? Since the heavy workers exposed to high temperature perspirate profusely, and since vitamin C is excreted in sweat, deficiency of vitamin C due to profuse perspiration may be suspected as a cause of the atrophy. Actually it is proved by vitamin C test in urine that the heavy workers exposed to high temperature are suffering from deficiency of C. In order to substantiate this finding, guinea pigs were fed with oat and C-avitaminosis was produced. The animals thus fed developed the sign of gingival atrophy. Macroscopic as well as microscopic examinations proved that the atrophic change is similar to that observed in human beings, suggesting that vitamin C deficiency may most probably be the principal etiology of the gingival atrophy.

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Changes in the tooth health rate (D.M.F.T.) in relation to the increasing number of pregnancy were statistically examined on 1153 pregnant women, and the following conclusion was reached. With the increasing number of pregnancy the tooth health rate decreased.

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We prepared the periodontal pack which was simplified the Kirkland-Kaiser's pack itself by our design, it's as follows. The simplified perodontal pack ; It consists of powder and liquid Powder {Zinc oxide Rosin equall Liquid {Eugenol 2 Peanut oil 1 Sandarac 6 Cinnamon oil a few drops We recognized that the pack is very effective to keep unwellness away from the after-bleeding and dentinsensibility by it is applied after gingivectomy

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