CRDTS Local Anesthesia Practice Test 2026 – All-in-One Guide to Mastering Your Certification!

When you perform an infraorbital nerve block, the injection sits near the infraorbital foramen where the infraorbital nerve travels through the infraorbital canal and into the midface. The area also hosts branches of the facial nerve that supply muscles of facial expression (such as those around the eye and mouth). If the local anesthetic spreads beyond the intended target or is given in a larger or deeper volume, it can reach these motor fibers and temporarily disrupt their function on the same side. That transient diffusion can produce facial nerve paralysis, with weakness of facial muscles in the affected region, which typically resolves as the anesthetic wears off. The other blocks involve different nerves in the maxilla or mandible and are less likely to affect the facial nerve’s motor branches.