Which injection is typically used to anesthetize the mandibular teeth on one side?

• A. Inferior alveolar nerve block
• B. Posterior superior alveolar injection
• C. Mental nerve block
• D. Incisive block

Answer: (A)

Anesthetizing the mandibular teeth on one side is achieved most effectively by blocking the inferior alveolar nerve as it enters the mandibular foramen. This nerve carries sensation to all the lower teeth on that side (molars through canines and often premolars) and, as it travels with the lingual nerve, also provides sensation to the floor of the mouth and the tongue. Depositing anesthetic in the pterygomandibular space interrupts the nerve before it branches, producing profound numbness of the teeth and adjacent tissues on that side.

The other options don’t fit as well. A posterior superior alveolar injection targets maxillary teeth, not mandibular. A mental nerve block only numbs the soft tissues of the chin and lower lip (and the mucosa near the mental foramen), not the teeth. The incisive block can numb the anterior mandibular teeth on one side but typically does not cover the posterior teeth like molars.