Sensory innervation of mandibular teeth by the nerve to the mylohyoid: implications in local anesthesia

Abstract

Traditionally, the nerve to the mylohyoid has been considered a motor nerve. However, dissection and clinical studies have challenged this dogma implicating the nerve to the mylohyoid as a nerve of accessory sensory innervation to mandibular teeth. Within the infratemporal fossa, the nerve to the mylohyoid branches from the inferior alveolar nerve and may be anesthetized with an inferior alveolar nerve block. However, because of the variability in location of branching and the potential barriers formed by both the pterygomandibular fascia and the sphenomandibular ligament, the nerve to the mylohyoid may escape anesthesia in an inferior alveolar nerve block. This may prevent profound local anesthesia of the mandibular teeth and may account, at least in part, for the high failure rate of the inferior alveolar nerve block. Alternative local anesthesia procedures may be employed to ensure adequate anesthesia of the nerve to the mylohyoid is achieved. This review provides a background of anatomical and clinical research of the nerve to the mylohyoid and outlines techniques suggested for providing a neural blockade of the nerve to the mylohyoid.