What areas are anesthetized by local infiltration?

What areas are anesthetized by local infiltration?

• A. Pulp and root of the tooth, buccal periosteum, connective tissue, and mucous membrane
• B. Pulp only
• C. Lingual mucosa only
• D. Buccal mucosa only

Answer: (A)

Local infiltration anesthesia works by placing the anesthetic solution directly into the tissues around the tooth apex. In the maxilla, the bone is porous enough that the drug diffuses from the injection site to reach the tooth’s pulp and its root, numbing the tooth itself. At the same time, the surrounding soft tissues—buccal periosteum, the connective tissue around the tooth, and the overlying mucous membrane—absorb the solution as it diffuses, so these tissues become numb as well. That combination is why the best answer includes the pulp and root of the tooth along with the buccal periosteum, connective tissue, and mucous membrane. Infiltration doesn’t reliably anesthetize only the lingual mucosa or only a single tissue type; those areas would require different techniques or additional infiltration.

Local infiltration anesthesia works by placing the anesthetic solution directly into the tissues around the tooth apex. In the maxilla, the bone is porous enough that the drug diffuses from the injection site to reach the tooth’s pulp and its root, numbing the tooth itself. At the same time, the surrounding soft tissues—buccal periosteum, the connective tissue around the tooth, and the overlying mucous membrane—absorb the solution as it diffuses, so these tissues become numb as well. That combination is why the best answer includes the pulp and root of the tooth along with the buccal periosteum, connective tissue, and mucous membrane. Infiltration doesn’t reliably anesthetize only the lingual mucosa or only a single tissue type; those areas would require different techniques or additional infiltration.