Indications A painful dental condition (toothache) or its treatment: Fracture (bone, alveolar ridge, or teeth) Dental caries Dry socket Mild to moderate tooth abscess (only if the abscess is sufficiently small that local infiltration will provide adequate anesthesia; otherwise, a nerve block is used) Contraindications Absolute contraindications Allergy to the anesthetic agent or delivery vehicle (can usually choose different anesthetic) Absence of anatomic landmarks needed to guide needle insertion (eg, due to trauma) Relative contraindications Infection in the path of needle insertion: Use nerve block, or other anesthesia.