Extracellular Administration of Lactate Dehydrogenase and Its Effects on Human Plaque pH and Acid Anion Concentrations

Abstract

The effect of lactate dehydrogenase (LDH) on human plaque pH and acid anion concentrations in vivo was investigated. Rinsing with sucrose solutions supplemented with LDH (1 or 2 U/ml) gave rise to reduced pH fall, decreased cH area and an increase in the mean minimum pH when compared with rinsing with sucrose only (p < 0.05). Mean acid anion estimations showed that plaque fluid concentrations of lactate, acetate and proprionate significantly decreased (p < 0.05) following rinsing with sucrose containing LDH at both levels and decreases in succinate when 1 U/ml LDH was present, whereas formate concentrations were only significantly lower when 2 U/ml LDH was added to sucrose rinses. It is thought that the ability of LDH to produce an alteration in the acid end-products of plaque metabolism may provide some protection against dental caries.

Comparative Reduction of Enamel Demineralization by Calcium and Phosphate in vitro

“…In principle, the chemical properties of this interface can be altered to decrease the cariogenic challenge originating from the metabolism of the oral flora. Several agents have been advanced as constituents of mouthwashes to minimize enamel demineralization, for example, lactate dehydrogenase [Higham and Edgar, 1991], urea and fluoride [Pearce, 1982[Pearce, , 1984Pearce and Nelson, 1988;Pearce et al, 1991], calcium phosphate [Stralfors, 1964;Rankine et al, 1989], calcium lactate [van der Hoeven, 1985;Shrestha et al, 1982;van der Hoeven et al, 1989;Kashket and Yaskell, 1992], calcium glycerophosphate [Bowen, 1972;Grenby and Bull, 1975;Sidi and Wilson, 1991] …”