It is generally believed that the lactobacillus count in a measure of susceptibility for tooth decay of the public as well as the acidogenic potency in a mouth. However, numerous facilities and materiales which can be available in only civilized countries should be equipped on its practice.
Sputocrit estimation of Lactobacillus count was originally found by Kondo and Onisi in their findings that bulk of oral desquamates obtainable in a gargled water is parallel with populations of organisms belonging to the glycolytic layer in the mouth, such as Streptococci, Veillonella, Lactobacilli, and Micrococci. Their findings, however, based on the results that were obtained from bulk of desquamate which was sedimented under 10000 rpm centrifugation. In the present work, a 800 rpm very popularhand centrifuge was used.
The obtained bulks of desquamates in such way, significantly correlated to the intraoral. populations of Str. salivarius, Str. mitis, and Veillonella, but not to Lactobacilli and Fusobacteria at 1% level of significance.
Thus, use of hand centrifuge seems to be simple substitude of sputocrit estimation of latent glycolytic potency in the mouth of the school children.
For the sake of caries susceptibility, number of DF cavities and carious teeth were also counted, but results insignificantly correlated to the bulk of desquamates. Another possibility of neutral correlation between actual cavities and desquamation was discussed to be an inexisting relation.

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During the period from September 1961 to March 1962, we gave health guidance for 3-year-old babies under the provisions of the Juvenile Welfare Law in various health centers of Metropolitan Tokyo. Of the guidance slips entered during the medical examination, we picked up 33, 395 slips in which complete dental views had been entered. Classifying these data by the different months of birth of the 3-year-old babies, we conducted a comparative study of dental disease with different months of birth, with the following results:
I. On dental Caries
1) The percentage of those suffering from dental caries is the lowest for the babies born in January-April, followed by the respective periods of September-October and May-August, The month with the lowest percentage is February with its 60.59%, while the highest month is May with its 77.78%.
2) As for the average number of decayed teeth per capita, the variation with different months of birth is comparatively similar to that of the number of sufferers from dental caries. The minimum is 2.97 pieces for January, and the maximum is 5.33 pieces for July.
3) The conditions of dental caries are classified into three types:
Type A: Those who have dental caned only in the front teeth or only in the molar teeth of the upper and lower jaws.
Type B: Those who have dental caries in the molar teeth of the upper and lower jaws and in the front teeth of the upper jaw.
Type C: Those who have dental caries both in the front and molar teeth of the upper and lower jaws.
For these three types, the variation with different months of birth is found as follows:
1) In Type A, the lowest percentage is 31.70% in July, and the highest is 54.15% in February.
2) In Type B, the tendency is reversed to that of Type A, the lowest being 34.90% in February and the highest 63.41% in July.
3) The trend of type C resembles that of Type A, the lowest being 4.76% in May and the highest 14.18% in April.
II. On Malocclusion
The variation of malocclusion with different months of birth is not very striking, but it is to be noted that those who were born in May show no malocclusion. The following are the percentages of different types of malocclusion: a) reversed occlusion, b) upper jaw projecting overpalate occlusion, c) open occlusion, d) fasciculation, and e) medium separation,
1) For type-a, November-March is the period of lowest percentage and June-October is that of the highest. Specifically, April gives the lowest percentage of 25.00% and June the highest 100.00%.
2) For type-B, April-July is the lowest period, followed by the periods of August-October and November-February upward in this order, The lowest percentage is 0% for the period of March through July and the highest is 12.68% for November.
3) The tendency of type-c is similar to that of type-b. The lowest percentage is 0% for April-July and the highest is 21.43% for March.
4) The tendency of type-d resembles that of type-c or type-a. The lowest percentage is 0% for March and May-July, and the highest is 50.00% for April.
5) For type-e, June is the lowest month, followed by December-February, March, April and July steadily upward. The lowest is 0% for June and the highest is 50.00% for July.
III. On Soft Tissue Disease of Oral Cavity.

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The following are the results of our investigation on decayed and lost teeth and food preference, which was carried out on a total of 4, 138 fifth-grade pupils (2, 028 boys and 2, 110 girls) in the elementary schools of Koto Ward, Tokyo in the 37th year of Showa (1962).
1. As for their decayed and lost teeth, the comparison between national figures and those of the pupils in Koto area reveals the following:
1) The cases of untreated dental caries among Koto pupils amount to 65.4%, lower than the national average by more than 10%.
2) The number of decayed teeth per capita is 0.7 in Koto, about 1 fewer than the national figure.
3) When dental caries is observed under different classes of C₁, C₂, C₃ and C₄, the percentages of the decayed teeth under C₁, C₂, C₃ and C₄ against the total number of teeth are respectively 3.7%, 1.7%, 1.4% and 0.4%. Compared with the national percentages, those of C₁, C₂ and C₃ are respectively about 60% of the national ones, while C₄ takes up almost the same percentage as the national one.
4) The lost teeth among the Koto pupils account for 0.4% of the total number of teeth, somewhat higher than the national percentage.
5) As viewed from the above records, the status of dental sanitation for the pupils in Koto Ward is considered to be better than the national status.
2. As the result of our investigation on the unbalanced diet habit of the pupils in Koto area, it is known that the unbalanced diet occurs more frequently in those who are free of dental caries than in those who have decayed teeth.

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Many reports have been made on the studies of the influence of noises upon a living body and it is generally accepted that noises make bodies sympathetic conditions at least. Our colleagues, Dr. Itakura and others, who made physiological analysis of unpleasant sounds, observed by GSR the influence of unpleasant sounds upon living bodies and reported that unpleasantness related rather to frequency of sound than to loudness.
We made experiments, with the stomatic movement as as an index, on sounds with different frequencies with the use of rabits to observe what influence would be caused to their bodies by the stimuli of sounds with different frequencies. In this experimerit in which Saloon method was applied as an index, four kinds of sound: 250; 1, 000; 4, 500 and 15, 000c/s respectively, were given to rabits through a lond speaker. The experiment has brought the following results; (1) all unpleasant sounds repress stomachic movement, (2) as stimulus is given for a longer time, the repress effect maintains longer and (3) sound with frequency of about 4, 500 c/s gives the greatest influence on the stomatic movement.
From these reasons mentioned above, we positively concluded that magnitudeo finfluence of unpleasant sounds upon living bodies depended on frequencies of sounds.

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