Why does infiltration anesthesia work better in the maxilla than the mandible?

Why does infiltration anesthesia work better in the maxilla than the mandible?

• A. Mandible more dense
• B. Maxilla more dense
• C. Mandible is thinner
• D. Maxilla bone is thinner

Answer: (A)

Infiltration anesthesia relies on the anesthetic diffusing through bone to reach the nerve fibers near the tooth apex. The maxillary bone is less dense and more porous than the mandible, with thinner cortical plates and more trabecular (cancellous) bone, so the anesthetic can diffuse to the nerve more readily. The mandible has dense, thick cortical bone that resists diffusion, making infiltration less effective there. So infiltration works better in the maxilla because the bone is less dense, which is why the statement that the mandible is more dense explains this difference.

Infiltration anesthesia relies on the anesthetic diffusing through bone to reach the nerve fibers near the tooth apex. The maxillary bone is less dense and more porous than the mandible, with thinner cortical plates and more trabecular (cancellous) bone, so the anesthetic can diffuse to the nerve more readily. The mandible has dense, thick cortical bone that resists diffusion, making infiltration less effective there. So infiltration works better in the maxilla because the bone is less dense, which is why the statement that the mandible is more dense explains this difference.