Draw and explain the Stephan curve in relation to diet and caries.
(5)
 pH of a caries free individual is generally higher (7) than someone with active caries (5.5).
 Repeated/frequent consumption of sugars, in the presence of Microbes, produces acid
dropping the pH value, thereby leading to demineralization.
 A glucose rinse in both caries free and caries active patients indicates that the fall in plaque
pH is greater in caries active individual.
 The pH of caries free patient is always higher even after glucose rinse.
 Return to normal pH after acid attack is quicker for caries free individuals.
 After attack it takes between 30-60 minutes to return to normal pH.