The AMSA injection: a new concept for local anesthesia of maxillary teeth using a computer-controlled injection system.

This article describes a new injection technique for the maxillary arch that achieves pulpal anesthesia of the central incisor through the second premolar without collateral anesthesia of the face and muscles of expression. This palatal injection can be delivered easily, consistently, and virtually imperceptibly with a recently introduced computer-controlled local anesthesia delivery system. The anterior (AMSA) middle superior alveolar block, is a single-site injection requiring less than one cartridge of anesthetic and is ideal for maxillary esthetic restorative dentistry because it does not distort the smile line. A clinical example is also presented.