Lesson 3: Saliva

Image:  Mouth with saliva.

Dr. Lee to Sara: "Have you ever wondered why your mouth makes spit? It is very important for healthy teeth."

The liquid in your mouth is called saliva, or spit. Healthy saliva is pH neutral or slightly alkaline. pH is a term used to indicate acid or alkaline, 7 is neutral, below 7 is acid and above 7 is alkaline. Saliva has five major functions:

  1. Lubrication of the mouth, tongue, and teeth. Xerostomia is a condition also known as dry mouth because not enough saliva is produced.
  2. Self-cleansing.
  3. Digestion of carbohydrates.
  4. Neutralization of acid caused by plaque bacteria.
  5. Remineralization, which is the opposite of demineralization, whereby tooth enamel is restored.

The amount of protective saliva in the mouth decreases at night, which makes brushing well before bed especially important.