STUDIES OF CHANGES IN pH PRODUCED BY PURE CULTURES OF ORAL MICRO-ORGANISMS
II. COMPARISON OF DIFFERENT MICRO-ORGANISMS AND DIFFERENT SUBSTRATES
ROBERT M. STEPHAN 1 and
ELIZABETH S. HEMMENS 1
1 Walter G. Zoller Memorial Dental Clinic, University of Chicago, Chicago, Ill.
A comparison has been made of the pH curves produced by pure cultures of different types of oral micro-organisms at high cell-concentrations (33% by volume) with various carbohydrates, lactic acid and urea as substrates. The differences in the pH curves produced by different micro-organisms suggest that in addition to the ability of micro-organisms to produce acid, the inability to consume acid and the inability to produce alkaline substances are also of importance in regard to the etiology of dental caries.
Submitted on October 18, 1946
