Most snakes have two rows of teeth on each upper jaw and one row on each lower jaw. All of the teeth are short and hook like. All non-venomous snakes have constrictor dentition, regardless of whether or not they actually constrict their prey.

Venomous (toxic) snakes are either groove fanged or hollow fanged.

Groove fanged snakes have only one row of teeth on each upper jaw, plus a pair of fangs. The fang has a groove that serves as a path for the venom to flow into the prey from the venom glands located on the top of the head.

With hollow-fanged snakes, their teeth serve the same purpose as with groove fanged snakes, but their fangs are more like a hypodermic needle through which the venom flows. Snakes with hollow fanged teeth can be either erectile or fixed. The erectile teeth are retracted into a groove on the roof of the mouth and extend when the mouth opens to strike. In snakes that have fixed fangs, they are always extended.

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