Some experiment were made on relationship between load and tooth-mobility (from lingual to labial side) by using the measuring apparatus of tooth-mobility applying a dial gauze, which was previously reported by Kimura and Ishibashi.
The results obtained are as follows :
1. The tooth-moving from lingual to labial side is rather influenced by the magnitude of the load. Different measuring position causes variation of measued value even in the same tooth. Therefore 1n case of measuring tooth-mobility, it is always necessary to use invariable load and to keep a constant measuring position.
2. With a gradual increase of the aspects of tooth-mobility is changed in accordance with the sort of the tooth. In case of intact teeth it can be obserbed to reach the limitation of their moving by the weight of about 1.2 kg. to 1.5 kg., and if the weight increases above 1.5 kg., those teeth are scarcely moved, On the other hand, in severly unstable pathologic teeth, the more increases the weight of load, the stronger becomes the tooth-mobility. In case of acute gingivitis, teeth are apt to move in their first stage and the mobility seems to decrease in accordance with their progress.
3. As the result of adding 1 kg, load on the same tooth 15 times repeatedly it can be observed that the mobility scarcely increases in case of intact teeth. On the other hand, in pathologic teeth the mobility increases more and more, and such inclination is remarkably observed in case of the teeth attacked by the progressive stage of alveolar pyorrhea.

View full abstract

Clinico-pathological considerations acere made in the summarized 226 cases of Cancer of oral region which had visited the Clinic of Oral Surgery, Tokyo Medical and Dental University during twentytwo-year period Since 1930 to 1951.
First, frequency of the occurence, etiologic factors, case history, clinical examinations, diagnosis, treatment and its result were discussed and the grade of clinical malignancy was determined on the basis of the stage and cli nical Progress of the lesion.
Secondly, histo-pathological examination was made in some cases and its relationship to the malignancy grade was discussed.

View full abstract

A 10-year-old boy with nothing peculiar in his family history is presented. Since he went to a swimming pool on August 1, 1951, he had suffered from a severe fatigue. Fever rose up to about 40°C on Aug. 10. The disorder was diagnosted by a doctor as troubles due to parasites. He was admitted to our clinic Aug. 18 with a complaint of swelling of the left mandible and itchy feeling. The red cell count gradually decreased with a high fever Aug. 28. Puncture of the bone marrow on Sept. 1 revealed a marked decrease of the nucleated erythrocyte and megaloblast. A diagnosis of aplastic anemia was made. As the systemic condition became better in the beginning of October, he was discharged from the hospital Oct. 20.
He felt a fatigue again after playing base ball on Jan. 17, 1952 and so he was hospitalized again. The then blood finding was as follows: W. C. C. 620, R. C. C. 1.2 million, and Hb-content 28 percent. He got worse in his systemic condition and died Feb. 11, 1952.
Autopsy Showed the findings of aplastic anemia.

View full abstract

The author presnts two skulls with bilateral multirooted first bicuspids, on which very few reports have been described so far. Their age and sex are unidentified, but probably they are the adult ones because of their worn surface of the teeth.
The one shows bilateral three-rooted upper first bicuspids and two-rooted lower first bicuspids, wheile the other shows bilateral two-rooted lower first bicuspids.
The sizes of these teeth were measured according to “Standnrd of Meafurement of the Teeth” by Fujita.
As a consequence the sizes of these teeth are not so different from the average ones of the bicuspid and excessive formation of the root can be considered as a good, example of “atavism”.

View full abstract

In the mouth of a man, 20 years old, who had been suffering from tuberculosis in both lungs, typical tuberculous ulcer of gingiva was formed. The ulcer was loceted on the gingiva and mucous men-brane. between the part of cuspid and that of second molar in the left side of upper jaw. This was treated by the injection of streptomycin and the applying of salve with it, and observed local healing in the comparatively early time. The total amount of used streptomycin was 10 g.. During the treatment, no systemic disturbance, unpleasant symptoms and by-effect were seen.

View full abstract

There are three kinds of disturbances ; they are
1) fracture of the denture base
2) fracture of the clasp
3) broken or displacement of the artificial teeth from a denture
To determine the frequencies and portions of these disturbances, we have made a clinical sur-vey of the broken dentures.
The purpose of this survey is to improve the way of repairing dentures or to find the measure of prevention.
The cases examined were not selected of the 184 fractured bases, 127 were removable partial dentures, 91 in the upper and 36 in the lower and 57 were complete dentures, 48 in the upper and 9 in the lower.
Approximately twice of five fold as many were found in the upper dentures as in the lowers. In the complete dentures, cracks were .originated mainly from median line or cuspid areas.
In the removable partial dentures, fracture were originated from anchored area of clasps, area of isolated remaining tooth and boundary between bar and base material.
The percentage of broken artificial teeth of upper dentures was larger than that of lower, 2 times in partial dentures and 4, 3 times in complete dentures.
Anterior teeth (incisors and cuspids) had larger percentage than that of posterior teeth.
Broken clasps were found in the upper dentures of 18 and in the lower denture of 12.
The cause of these damages seemed to resolve into malconstru, .tion and inadequate indikation of clasps and not material itself (18-8 steel wire or co-cr wire) .

View full abstract