Question

above it is written that tooth decay starts when pH of mouth is below 5.5 but in the lesson 4'strength of acids and bases' it is given that pH of saliva is 5.33.then why not tooth decay start only with saliva?

Answer 1

pH of saliva is close to limiting value of pH of mouth for tooth decay. Whenever we eat something, our saliva acts on it to digest the carbohydrates, this decreases the pH of the mouth well, below 5.5, which thus triggers the tooth decay.