Nerve distribution in the dental pulp has been studied on a large number of human teeth freshly extracted from the mouth, by means of nerve staining using the urea and silver nitrate staining and gold staining methods. The results obtained are summarized as follows. 1) Sensory nerve fibers were present exclusively in the odontoblast layer and in the young dentin, but not in the ground substance of calcified dentin, nor was there found any nerve fiber extending into the dentinal tubules. 2) It was presumed that sensation upon the dentin was received and transmitted by way of Tome's fibers representing the processes of odontoblast cells. It is also the authors' opinion that the vegetative nerve fibers present in the wall of pulpal blood vessels may have certain role of physiological significance in connection with the sensibility of pulp and the function of odontoblasts.

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Courses and distribution of the nerve fibers in the periodontium has been studied on dogs, cats, rabbits, gunea pigs, mice and albino rats, and the following results has been obtained. 1) The nerve fibers supplying the periodontium came to distribute there from the bottom, wall, and crest of the alveolar bone, all the way beind accompanied by blood vessels. 2) In the periphery, however, this parallelism of nerves and blood vessels became obscure, and there remained only network ramification of the nervc fibers to be seen. 3) Exit of the nerve fibers from the periodontium took place partly through the walls of the alveolar bone toward into the bone marrow, and partly through the periodontium at the cervical region toward the gingiva. 4) Patterns in which the nerve distributed in the periodontium differed among two groups of carnivorous and rodent animals examined, in the following manner : a. In the carnivorous animals, the nerve developed into large plexus at the portion beneath the root apex, though it became rarefied toward upper part of the root. In the rodents, however, the nerve distributed almost uniformly over entire periodontium from the root apex to the cervical region of the teeth. b. In the rodents, the nerve fibers distributed very close to the alveolar bone, while in the carnivorous animals, the nerve fibers were seen relatively abundantly even in the vicinity of the cementum. c. With the rodents' incisors, the pattern of the nerve distribution on their labial and lingual surfaces was quite different one from the other. 5) There failed to be seen any single nerve fiber entering into the cementum. 6) The nerve endings allowed to be discriminated grossly into three forms, branchings, non-branching and glomerate, and in the carnivorous animals, the complicated branching form of nerve ending was more frequently observed than in the rodents examined. 7) In view of the forms in which the nerve endings occurred, it was presumed that the periodontium served mainly to receive tactile sensation, and partly also pain sensation.

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Changes in the tooth health rate in relation to the increasing number of birth were statistically examined on 565 birth women. The results were summarized as follows. With the increasing number of birth their tooth health rate (caries incidence, average number of existing teeth and DMF teeth) decreased remarkably.

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Lingual papillae were studied on a male lama (Lama huanachus Mol.) aged 4-5 old. The results were summarized as follows. 1) Lingual papillae viewed Papillae vallatae, Papillae fungiformes, Papillae filiformes as another Mammalia, but not Papillae foliatae. (a part of Papillae foliatae viewed only simple unevenness) 2) Papillae vallatae were very large, longitudinal diameter 3∿6mm, but their taste buds were few in the rate of the size

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During the course of the study on the developmental process of oral cavity in the human embryo, the authors found unexpectedlly an epithelial pearl appearing in the Lamina propria of P. vallatae in the human embryo 9 and 10 months old. The results were summarized as follows. 1) The epithelial pearl in the 9 month embryo showed the typical features with its longitudinal diameter of 510 micron, and its width of 430 micron. 2) On the histological finding of the epithelial pearl. The outer layer consisted of one or two layers of columnar epithelail cells, and within it, there appeared a concentric circle of very thin squamous cell layer, and a part the center is degenerated to horny or corneous layer with scattering nuclei, and another part to the so-called chylous condition.

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Measurement of the mandibular movement in the free directions has been one of the major problems in the field of dentistry, to which various approaches were attempted by many investigators. To date, however, no adequate method of measurement in this line is yet available. This is presumably because of the inconveniences encountered in the procedure that the mandible takes not only three dimensional, but also apparently irregular directions in its movement, and further that any tooth to serve as target of measurement is normally concealed from the view inside the mouth not to permit direct observation. The present author has devised a new method of measurement in which the movement of the mandible was taken on the same movie films from two right angled directions, utilizing Dr. Yokota's cephalometric photo-apparatus. By this method, most of the inconveniences hitherto experienced are believed to be successfully eliminated. The outline and main features of the method are summarized as follows. 1) The basis for measurement of the mandibular movement was laid on the maxillar bone in the present method for the purpose of obtaining true value of the movement. This is in contrast with all methods heretofore adopted, except for ths simple tracing method. Since the basis for measurement was placed outside of the subject in those methods, there was always danger of counting any incidental sway of the head into that of the mandible. This was proved true in one of the preliminary experiments where the maxilla of a subject as measured on the suborbital point was dragged upward reflexly in vertical distance by 9.0mm, when he was ordered to open his mouth as wide as possible, even though his head was seemingly kept in a fixed position. 2) High accuracy of measurement could be expected with this method as far as the enlarging capacity of the film could afford. In the present experiment, the pictures obtained were enlarged by two-fold to secure the accuracy within 1/10mm, but the higher accuracy may readily available by increasing the rate of enlarging. 3) Another feature of this method is that direct observation of the mandibular movement can be realized from outside of the mouth, regardless of whether the portion to be measured lies hidden in the mouth or in tissues. This was rendered possible in the present method, by placing a marker outside the mouth which is directly connected to the portion concerned, and by tracing its movement successively with the movie films. 4) There was attached neither a marker nor any cumbersome appliance on the target point to hinder the natural movement of the mandible during the experiment, and this also ensured true observation. 5) The progressive movement of the mandible can be directly recorded in the films three-dimensionally at every desired moments of time, and the pictures simultaneously projected on both frontal and sagittal planes allow to be analyzed three-dimensionally. Using this apparatus, a series of preliminary measurement was conducted on the movement of the mandible, taking the distal angle of lower left central incisor and the mesial buccal cusp tip of lower left first molar as the targets. Since main object of the present study was to make sure whether or not the apparatus could work sufficiently well to yield desired efficacy, gross directions of the mandibular movement such as those occurring in the maximum opening of the mouth and the bilateral movement of it were studied for the sake of clarity. These studies have clearly shown that the pictures obtained from tracing the marker of the apparatus accurately represented the three-dimensional movement of the target on the mandible. Although the loci produced in the maximum opening of the mouth were similar with both reciprocal pathways in the general pattern, they were not identical in minute detail, and showed the largest divergence at the middle portion of the stroke. Thus the

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A 12-year-old female Grant's Zebra died from acute meteorism. We dissected her about 10 hours after death and obtained following views. 1) Meteorism (high degree) 2) Perforation of dilatation gasticus 3) A faecal calculus of 967 grams in dilatation gastricus 4) Perforation of diaphragm 5) Panperitonitis 6) Ulcer of illeum 7) Erosion of stomach 8) Fluid blood 9) bleedings (peritoneum, diaphragm, stomach, right kidney, trachea, urinary bladder) 10) Glottis-oedema 11) Gravid uterus (a foetus aged about 6 months) 12) Degeneration of liver.

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The Spilocuscus maculatus minor is a small animal dwelling island of Manus and belongs to carnivorous suborder of placentalia. We dissected an adult, male Cuscus of 2 yars old died from marasmus and ulci in radix of tail and palmus of legs, etc, . Clinical findings showed the diarrhoea and depression of appetite and died with spasm of legs. The results obtained were as follows ; 1) Marasmus. 2) Ulci in radix of tail, palmus of legs and lower abdominal wall. 3) Eczema in perineum, glabella and lateral part of neck. 4) Hemorrhage or softning in central nervous system. 5) Degeneration of nervous cells and nervous fibers in central nervous system. 6) Stagnation, bleedings and small foci of necrosis in liver. 7) Gromerulonephritis and haematuria. 8) Catarrh in stomach and intestine. 9) Oedema in lungs. 10) Heamorrhage in heart. 11) Stagnation and bleedings in spleen. 12) Anisocolis. 13) Cicatrigation in conjunctiva. 14) Microbiologically, blastomyces-like organismus were cultivated from lesion of ulcer in radix of tail. 15) There were micro-histologically blastomyces-like micro-organismus in subdral parts, medulla, subependimal parts of encephalon and liver.

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We dissected a femal adult Red Panda died from bronchopneumonia. It was imported from Calcutta on 23rd, January, 1957. He was kept in a zoological garden about one year. Clinical findings before death showed pneumonia and diarrohea. The animal died on 3rd, January, 1957. The results obtained from dissection of the animal were as follows ; 1) Bronchopneumonia and bronchitis in both lungs. 2) Schistosomiasis japonica. a) Marasmus b) Numerous eggs in mucous menbrane of intestine and embolism of eggs in capsule of glisson c) Numerous wormus in portal vein. d) Hypertrophy of interlobular connective tissue in liver e) Ascitis. 3) Paragonimiasis. a) Numerous Parasitic noduls and eggs in both lungs b) Eggs around bronchus and blood vessels. 4) Catarrh in stomach. 5) Catarrh in duodenum and jejunum. 6) Catarrh and erosion in ileum. 7) Stagnation in spleen.

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Although fluorine was first isolated in 1886 by Moissan, its human toxicity as manifested in the mottled teeth incidence was first reported by J. M. Eager. The study of the disease was further followed up by G. V. Black and F. S. Mckay, from whom the name, mottled teeth, was originated. Fukui and Tomitori were among the earliest investigators of our country in the study of this problem. During two years period from 1958 to 1959, we conducted a survey on the mottled teeth incidence among children of Tobata city primary schools, with respect to rate of occurrence, number of teeth involved, susceptibility of individual teeth, classification of the disease severity and also to the possible relation of mottled teeth to dental caries incidence. The results obtained are summarized as follows. 1) The mottled teeth incidence amounted to 2% in the average among whole subjects examined, of which it was low in the lower class and high in the higher class of children. 2) Most frequently a single tooth among the dentition was attacked by mottling, and accordingly, multiple mottled teeth incidence was lowered with increasing number of teeth attacked. 3) On classifying the mottled teeth by severity, there were 99.7% of M1 and 0.3% of M_3B found, with no intermediate severity. The mottled teeth with M_1 severity allowed to be further classified by their forms into dotted, linear, striped and speckled.

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