The type of teeth a snake has is dependent upon how the species catches food.
All non-poisonous snakes have teeth on the upper jaw and the lower jaw. A snake can often grow more teeth as needed because teeth are sometimes lost while feeding. The teeth are hook-shaped and angle toward the throat.
Poisonous snakes have either grooved or hollow fangs. The poison, which comes from glands located under each eye, flows down the groove or through the hollow portion of the fangs and is injected into the prey.