The Nerve Blocks animations shows where Dr. Mark Piper injects a nerve blocking agent during a patient examination. Learning how to perform nerve blocks can help a dentists to determine the orginin of a patient's pain. Many patients with migraine pain are misdiagnosed by their physicians as having TMJ pain, while many patients with TMJ pain are misdiagnosed by their dentists as having migraine pain. So, how do physicians and dentists accurately identify the real cause of pain? The nerves in the head and neck may provide the answer.