Which injection numbs the lower lip?

Which injection numbs the lower lip?

• A. Inferior Alveolar Nerve Block
• B. Posterior Superior Alveolar Nerve Block
• C. Infraorbital Nerve Block
• D. Mental Nerve Block

Answer: (A)

Lower lip sensation is carried by the mental nerve, a branch of the inferior alveolar nerve. When you give an inferior alveolar nerve block, the anesthetic is placed near the mandibular foramen where the inferior alveolar nerve is before it splits to the mental nerve. This blocks the nerve signals to the mandibular teeth and, via the mental branch, to the lower lip and chin, so the lower lip becomes numb. The other blocks target the maxilla or midface and don’t affect the lower lip. The mental nerve block would numb the lower lip specifically, but it’s a more localized approach; the inferior alveolar nerve block achieves that numbness as part of a broader mandibular anesthesia.

Lower lip sensation is carried by the mental nerve, a branch of the inferior alveolar nerve. When you give an inferior alveolar nerve block, the anesthetic is placed near the mandibular foramen where the inferior alveolar nerve is before it splits to the mental nerve. This blocks the nerve signals to the mandibular teeth and, via the mental branch, to the lower lip and chin, so the lower lip becomes numb. The other blocks target the maxilla or midface and don’t affect the lower lip. The mental nerve block would numb the lower lip specifically, but it’s a more localized approach; the inferior alveolar nerve block achieves that numbness as part of a broader mandibular anesthesia.