Effect of in vivo Addition of Selected Nitrofurans on Acid Production in Human Saliva.

Abstract

It had previously been demonstrated that 5-nitro-2-furaldehyde-2-B-methyl semicarbazone and 5-nitro-2-furaldehyde-2-B-hydroxy-ethyl semicarbazone are effective as inhibitors of acid production in human saliva when added in vitro in 500 [mu]g. quantities. In addition, these compounds are bactericidal against an oral strain of the Lactobacillus acidophilus when added in amts. of 3.5 mg. or more to yeast extract dextrose broth inoculated with the test organism. The incorporation of 1000 [mu]g. quantities of 5-nitro-2-furaldehyde-2-B-hydroxyethyl semicarbazone and 5-nitro-2-furaldehyde-2-B-methyl semicarbazone in paraffin blocks used as salivary stimulants completely prevented acid production in 38 of the 42 saliva samples obtained from caries-active individuals. A significant partial reduction in acid formation occurred in the remaining 4 cases. The findings indicate that 5-nitro-2-furaldehyde-2-B-hydroxyethyl semicarbazone and 5-nitro-2-furaldehyde-2-B-methyl semicarbazone are not rapidly destroyed or absorbed by the tissues and fluids of the oral cavity.