Oral Starch Degradation and Its Influence on Acid Production in Human Dental Plaque

Abstract

Enzymatic hydrolysis of starch by salivary α-amylase, its time dependence and influence on plaque acid production was investigated. Analysis of the composition of starch digests was performed with gel filtration chromatography. Wheat starch in solution, in bread and in biscuit was hydrolyzed rapidly mainly to maltose, maltotriose and limit dextrins. In vivo enzymatic degradation of wheat starch caused marked drops in interdental plaque pH to 4.75 measured by intraoral plaque pH telemetry, most probably as the result of the fermentation of low molecular weight maltodextrins by plaque bacteria. On this basis starch may contribute to cariogenesis.