The trigeminal nerve is the fifth cranial nerve. It is composed of three branches on each side of the head (hence “tri” and “gemini”). It has the largest number of sensory neurons of any nerve in the body (100 times more dense than any other nerve) and is represented on the brain sensory cortex by 28% of the surface area. The trigeminal nerve has three sensory nuclei that it sends information to in the brain, and one motor nucleus. One of the nuclei, for proprioception, is composed of the only sensory cell bodies in the brain. This is a very important aspect of the trigeminal nerve and accounts for much of why it has a major influence on brain function and health in general.
The fact that the trigeminal nerve has such a high density of pain fibers also makes it very special and influential on homeostasis (body health). With bite disturbances, the trigeminal becomes activated leading to the release of pain neuropeptides (substance P and calcitonin gene related peptide). Substance P is known to regulate many body functions, hence alteration in its normal level leads to a wide spectrum of medical disorders (Associated Medical Disorders). Elevated substance P has two primary effects on the body:1) hyper sensitizes all sensory neurons 2) primary mediator of inflammation. With hyper sensitization, the body over reacts to sensory input causing frequent illness. With increased inflammation, many neurogenic inflammatory disorders typically develop (cardiac disease, arthritis, IBS, migraine, skin disorders, seizures, auto immune disorders, etc.).
Correction of trigeminal nerve disturbances most often involves jaw alignment (TMJ treatment), but can also involve abscessing teeth, failed root canals, cavitations (osteonecrosis), broken jaws, etc. Jaw alignment is done with removable appliances with multiple adjustments (it is a process and not a procedure). An extreme case of trigeminal disturbance would be trigeminal neuralgia: typically treated improperly with surgery and not jaw alignment.