Tuesday, May 22, 2007

HUMAN NUTRITION PART 2: THE TEETH

MAIN FUNCTION OF THE TEETH
To break down food into smaller pieces so as to increase the surface area so that chemical digestion can be facilitated.

THE STRUCTURE OF A TOOTH
  • Enamel is the hardest substance which is very difficult to break or chip. However it can be dissolved by acids produced by bacteria as a result of feeding on sweet foods left on the teeth.
  • Dentine is rather like bone. This is also hard but not as hard as the enamel. It has channels in it which contain living cytoplasm.
  • Pulp cavity contains nerves and blood vessels. The blood vessels supply the cytoplasm in the dentine with food and oxygen.
  • Cement has fibres growing out of it. These attach the tooth to the jawbone but allow it to move slightly when biting or chewing.
TYPES OF TEETH
MAMMALS HAVE TWO SETS OF TEETH IN THEIR LIFE
  • The first set is called the milk teeth consisting of 20 teeth (8 incisors, 4 canines and 8 premolars)
  • The second set is called the permanent teeth consisting of 32 teeth (8 incisors, 4 canines, 8 premolars and 12 molars)
GUM DISEASE


TOOTH DECAY

PREVENTION OF GUM DISEASE AND TOOTH DECAY
  • Stop or reduce taking too much food containing or made of sugar. Brush teeth or at least rinse mouth immediately after taking food containing sugar.
  • Use a fluoride toothpaste regularly. Fluoride make your teeth more resistant to decay.
  • Visit the dentist to have a dental check up at least twice a year.