Dental Caries Prophylaxis

By Carl Schioetz
Oslo, Norway
The author gives an account of investigations made in four homes for children in and around Oslo and in one such home in Stavanger, where the state of the teeth, in contrast to what is usual in Norway, was excellent –the teeth being practically free from caries. Dr. A. Collett has earlier published the results of his personal investigations in one of these homes (in 1930 and 1935), under his hygienic control.
Common Factors
In one of the homes the use of sugar was strictly limited, but not in the others. In some of them the tooth-brush was used, in others not. Common factors for all five homes were : –
1. Plenty of open-air life.
2. Strict arrangement of hours of sleep.
3. Dietary: every single day abundance of un-skimmed milk, brown bread, fresh fruit and/or green vegetables or roots.
This applied especially to four of the homes, the fifth having a somewhat smaller rations of milk and no systematically pursued use of fruit. Neither did it stand quite so well as the others with respect to the teeth.
In order to get a clear view of the hygienic side of the caries problem it is, of course, necessary to go farther than merely to these homes for children. But the main point must be to find common factors, and this is just what has been neglected. Investigations from their own small local material, and forget that the hygienic problem in caries is a worldwide problem which must be regarded at once form the standpoint of history, of geography (over the whole world) and of local case-records. It is only by considering these common factors that the problem can be solved.
From certain quarters it has been maintained that the main point is the physical consistence of the food, and not the chemical nature of the nutrients of foodstuffs. The author is greatly interested in food that requires chewing, as has been demonstrated in practice by the school breakfast composed by him and introduced in many cities and towns in Norway –the so-called “Oslo breakfast,” which comprises whole meal crackers or whole meal bread (“knekkbrod”), carrot or apple, as well as milk, brown bread and cheese, and at certain times of the year orange. Half an hour is fixed for this meal, in order that the children may have time to chew the food. On the walls of the eating-rooms in several schools is put up the following notice: “Never drink with food in the mouth.” This is the only method for ensuring the desired chewing –to urge the children –or adults (!) –to chew the food well is of no avail.
Thus the demand for thorough chewing is regarded with great interest by the author, but it is impossible to accept the consistence of the food as being the all-important point in caries prophylaxis. Certain primitive races (for example, Norwegian Lapps, especially in earlier times) had hard food and fine teeth. But the inhabitants of Tristan de Cunha, the Canary Islands, the Hebrides and of certain districts in Italy are practically free from caries, and yet their food is soft. On Tristan de Cunha the dietary consists of potatoes, vegetables, fish and milk, with addition of penguin eggs when they can be obtained. This latter fact also characterizes the other groups of people, as mentioned, inter alia, in a special dental number of the Wiener Klinische Wochenschrift, of July 31, 1936. Accordingly, a geographical consideration of the problem refutes the view that the consistence of the food is a condition sine qua non. But the use of food demanding vigorous chewing may have a favorable influence, which certain forms of soft food also have. The secretion of saliva, for instance, is greatly stimulated by vigorous chewing (directly stimulated as regards “knekkebrod,” cf. the same number of the Wiener Kl. Wochenschr.). It is also greatly stimulated by fruit of acid taste. Especially must be noted the harmful result of drinking with the mouth full; the salivary glands are not stimulated and the food is washed down half chewed. The common factor in caries prophylaxis can be therefore not be the hardness of the food. This hardness is at most an auxiliary aid, which can be dispensed with.
Sugar, Not Harmful
The carbohydrate theory must also be abandoned, since it is found that negroes on sugar plantations, who eat large quantities of sugar, often have faultless teeth, even if about 75 per cent of the calorie requirements is covered by carbohydrates, more than one-third of the total quantity of calories is represented by sugar. This does not preclude the fact.