Decomposition of Carbohydrate Substrates by Dental Plaque Material

Histotopochemical Determination of Metabolic Activity of Carbohydrate Metabolism in Plaque from Sound and Carious Enamel

“…A comparison of enzyme histiograms of both kinds of plaques, however, shows that the LDH activity found in plaque from carious enamel is only insignificantly higher than in plaque from sound enamel. This is in accordance with the findings of several investigators who were able to show by quantitative determination of lactate or enzyme activities in plaque homogenates that the amount of lactate or LDH activity did not differ strikingly in samples from 'caries-susceptible' and 'caries-resistant' subjects [Etherington and T rimble, 1934;M iller et al, 1940;T overud and H agen, 1957;EggersLura, 1958]. Due to the relatively low level of LDH activity which, incidentally, had also been demonstated by quantitative determination [G ari.ichs et al, 1969], it can be stated that the plaque microorganisms of both groups (PSE and PCE) meet their energy requirements both by anaerobiosis and (to a major extent) also by aerobic degradation of carbohydrates.…”

A Quantitative Method for Evaluating Physical and Chemical Agents which Modify Production of Acids in Bacterial Plaques on Human Teeth

“…Since some buffers, sulch as A1/10 N1a2FHI)4 were found to exert. only a negligible: ehfeet oni the 8 If the individuals studied by this method are allowed to partake of whatever food they may choose, many will eat a large amount of carbohydrate before the experiment. The effect of this carbohydrate may reduce the individual's initial pH values to such an extent that the effect of the experimental glucose rinse is considerably obscured.…”

“…"3 It has also been shown by Stephan (7) that plaques react rapidly with carbohydrates to produce acid, in some cases reducing the pH to as low as 4.0. Miller, Muntz, and Bradel (8) demonstrated that plaque material produces considerable quantities of lactic acid from glucose, sucrose, fructose, maltose, lactose, and starch. In susceptible individuals this acid may attack the underlying enamel and initiate dental caries.…”

The Respiration of the Salivary Microbial Flora and its Relation to Dental Caries Activity

“…DISCUSSION The rapid oxidation of glucose by caries-active saliva and the considerably slower reaction of caries-inactive saliva on this substrate could logically have been expected, although it was not previously found by others. 3 4, 4, , 10 Neuwirth and Summerson and many others5' 18,19 have shown that acid, especially lactic acid, is a major product of this oxidation. However, intensive investigations into the salivary pH and its relation to dental caries activity by numerous workers30-33 and others have failed to demonstrate any correlation between salivary pH and dental caries activity.…”