Early Administration of Various Carbohydrates and Subsequent Dental Caries in the Rat

Abstract

rARBOHIYDRATES, usually in the form of lactose, are a normal constituent of milk. Sognnaes,' from a study of rats which were kept on a high sucrose diet through several generations, concluded that the ingestion of sucrose during the formative period of the teeth affects the subsequent caries experience of these teeth due to a change in the maternal milk or due to the high sucrose diet eaten ad libitum after the eyes opened. The teeth of Rhesus monkeys formed during the period of a high sucrose diet also were susceptible to decay, whereas those formed before the animals were placed on a high sucrose diet were immune. An analysis of the caries experience of Scandinavian children during and after World War II tend to support this conclusion.2 The addition of ashed laboratory chow to the refined rations fed dams caused a decrease in the amount of decay produced in the offspring. This might suggest that the increase of caries on the refined diet alone was due to a lack of some important unknown constituent in the diet.3The period of development of the molars of the white rat from the beginning of calcification to eruption into the oral cavity has been shown by Hoffman and Schour.4 This period of developmental time for the first and second molars roughly corresponds to the suckling period. The calcification of the third molars involves only the last quarter of the suckling period and extends approximately 14 days beyond this date. To determine the possible effects that various carbohydrates may have on the molars from the beginning of calcification to their eruption into the mouth, this study was conducted. EXPERIMENTAL Stock animals obtained from the Naval Dental Research Institute, Bethesda, Maryland, were known to be caries susceptible on the Hopper, Webber, Canniff diet. These animals were also found to be caries susceptible on a high sucrose diet.All animals, after weaning, were placed on a high sucrose diet (Table I).The following solutions were administered to 8 groups of young rats during the suckling period by means of a calibrated eye dropper, 20 per cent sucrose, 20 per cent lactose, 20 per cent raw-cornstarch suspension, 20 per cent glucose, 20 per cent equal parts of glucose and fructose, and tap water.

A Technique for Tube-Feeding Newborn Rats, and the Effects of Administration of Various Carbohydrate Solutions on their Subsequent Caries Susceptibility

“…Under the conditions of this study, no evidence was forthcoming to support the findings of Steinman and H aley [7], who dropper-fed rats with 20 % sugar solutions 3 times a day from birth until 21 days of age, and reported that the increase in caries susceptibility was highest with sucrose and least with lactose. The present figures did not even show trends to support these findings, despite the fact that the total quantities of sugar received by the rats were far greater than Steinman and H aley delivered to theirs.…”

“…B rown and B ibby [1] reduced the mortality rate by beginning when the rats were 10 days old: however, by this time much of the first molar crown has already formed. The dropper-feeding technique used by Steinman and H aley [7] is more physiological, but is time consuming and, in our hands, inac curate. By passing a tube into the oesophagus of the rat, one has the combined assets of speed, accuracy and the utilization of the gastro-in testinal tract.…”

“…Kruger [4] gave daily, intraperitoneal injections to suckling rats, but the method has a high mortality rate, is unphysiological and limits the substances that can be given. Steinman and H aley [7] used a method of dropper feeding suckling rats but in an attempt to use this technique, the present authors found that only very limited quantities could be given and the amount actually ingested varied from rat to rat and apparently from substance to substance.…”

“…A suggestion by Sognnaes [6] that the consumption of a high su crose diet by albino rats during the formative stages of the teeth may ren der them more susceptible to decay has been supported by Stf.in m a n and Haley [7], but not by Brown and Bibby [1].…”

Acute Hemiplegia in Childhood

“…7., 1962, 2, 108. 6 Davies, D. P., ibid., 1964, 1, 695. Natural History of Atherosclerosis SIR,-The paper by Drs. C. J. Schwartz and T. A.…”