DENTAL DECAY

Otago Daily Times, Issue 27387, 12 May 1950, Page 4

DENTAL DECAY

Danger Of Excessive Brushing VALUE OF DIET Brushing teeth after every meal ■ or drink makes them more susceptible to dental decay. This is the conclusion reached after a year’s research in Wellington by Dr R. E. T. Hewat, working under the Dental Committee of the Medical Research Council. It was reached after 41 student dental nurses had observed strict dental hygiene for a year, the result being that dental decay had increased by 70 per cent, at the end of that time. A similar group of nurses was put on a diet containing ' a limited amount of carbohydrates for a period of six weeks during the year, and it was found that the effect of the diet gave a reduction of 30 per cent, in the amount of decay for the whole year, compared with a control group. The significance of the conclusion, Dr Hewat claims in a report published in the New Zealand Dental Journal, is the fact that it resulted from a clinical test as distinct from a bacteriological test. It would therefore appear, he adds, that there was an optimum level of dental hygiene which was not necessarily achieved by frequent daily brushing and rinsing. But the restriction of biscuits, cakes, sweets, chocolate, ice-cream, -free sugars and cordials, for a limited period did result in a reduction. of dental decay of 30 per cent, during the test period of a year. It was also found that the control measures of diet and hygiene had little difference in their effect on the start of decay on a tooth surface. The percentage of tooth surfaces which became newly decayed during the year was: Dietary group, 1.6 per cent.; hygiene group, 3.92 per cent.; uncontrolled group, 2.29 per cent. A total of 120 student nurses resident at hostels in Wellington were used for the experiment. They were divided into three groups—4l observing strict dental hygiene, 38 adhering to a set diet for six weeks, and 40 nurses who were given no instructions about either diet or hygiene. A thorough dental examination, at which the location of every filling was checked, and X-rays taken, was carried out on each nurse at the beginning and end of the test period. Dr Hewat states that it was thought preferable to restrict the number of nurses used in the test rather than risk any relaxation of the rigid regimen to which they were subjected. The nurses found it somewhat difficult to adjust themselves to the change in diet, and minor temporary discomfort occurred in some cases. They did not miss sugar, sweets, cakes, and biscuits as much as might be expected, their weight remained stable, and generally the experience resulted in enhanced mental' and physical alertness.

Dr Hewat intends to present observations later on the association of different degrees of dental hygiene with active dental decay. He was assisted in the experiment by Mr F. B. Rice and Miss May Abranam, of the Department of Health.