Cervicocephalic artery dissections occurring during dental care have exceptionally been reported. We describe a case of internal carotid artery dissection, presenting as hypoglossal nerve palsy, occurring immediately after difficult inferior alveolar nerve anesthetic block for third inferior molar dental care. Carotid dissection was successfully treated with anticoagulation therapy while hypoglossal nerve palsy recovered with carotid dissection shrinkage. The etiopathogenetic mechanisms of this singular form of internal carotid artery dissection are discussed. The possibility of internal carotid artery dissection development during oral or dental procedure, specifically in cases of possible trivial intraoperative internal carotid artery injury, severe local periodontal infection, or prolonged cervical hyperextension should be considered. Every possible prophylactic measure should be taken (eg, sedating the patient during oral or dental procedures, aggressive preoperative management of general and local periodontal chronic infections, avoiding prolonged perioperative neck hyperextention) to prevent this very rare but potentially life-threatening complication.