Which injection technique provides the longest duration of anesthesia?

The nerve block technique provides the longest duration of anesthesia compared to the other methods. This is primarily because a nerve block targets specific nerves that are responsible for sensation in a larger area, inhibiting their ability to transmit pain signals over an extended period. By causing a deep penetration of anesthetic into the vicinity of a nerve, it can effectively numb a broader region.

In contrast, infiltration and field block techniques are more localized. Infiltration involves injecting the anesthetic solution directly into the tissue, which typically results in a shorter duration of anesthesia because it affects only the immediate area surrounding the injection site. Similarly, a field block creates a barrier along the nerves that innervate a specific area, but it does not have the same lasting effect as a nerve block since it does not directly target the nerve trunk.

Thus, while all techniques have their uses and can provide effective anesthesia, the nerve block stands out for offering a longer duration because of its ability to more thoroughly obstruct nerve transmission over larger areas, making it a favored approach in various dental procedures that require extended periods of pain control.