Teeth are strong bone structure that grew out of the soft gums. Teeth firmly in the upper jaw and lower jaw. Each tooth consists of the top and bottom. Adults have 32 teeth with various forms and functions. In each jaw there are four incisors (insisivus) chisel-shaped, useful for gripping and cutting food.
Two canine teeth (kaninus) pointed for piercing and tearing food, and four premolar teeth are flat, along with a large molar teeth, for crushing and chewing food. Humans have two sets of teeth along his life. The first set consists of 20 milk teeth, between the ages of 6 and 30 months. The second set consists of 32 pieces of permanent adult teeth lined up in the gums. Since the age of six years, adult teeth begin to appear, replace the milk teeth out one by one. The last permanent teeth are growing behind the molar teeth during adolescence.
Lips and front teeth pulled food into the mouth. Strong jaw muscles that move the lower jaw up and down to destroy the food was interrupted by a large molar teeth. Three pairs of salivary glands release saliva into the mouth, and tongue chewed food mixed saliva premises. Tongue pushing food slippery lump, called a bolus, into the esophagus. Bolus triggering reflex muscle contraction called peristalsis. This movement was encouraged chewed food into the abdominal cavity to digest at a later stage.