When a person spikes the volleyball hard from the other team (or side), a person from the team opposite of the one who just spiked will block the ball and keep it off their si â¦ de.
Tooth decay is the destruction of your tooth enamel, the hard, outer layer of your teeth. It can be a problem for children, teens and adults. Plaque, a sticky film of bacteria, constantly forms on your teeth.
New research reveals that dental caries, also known as cavities or tooth decay, is actually an infectious disease. Dental caries cause the demineralization and break down of the enamel, dentin and cementum within teeth.