Tooth Hurty: Time for a Different Perspective

Dr Jack Parry 3 May 2026

keywords: tooth pain bruxism trigeminal nerve root canal central sensitisation myelin white matter dental

I grind my teeth. Not consciously, not deliberately, but reliably, in response to stress, at night, in ways my dentist can read from the wear patterns on my lower front teeth as clearly as a geologist reads stress fractures in rock. The jaw is clenching against something that is not there. The body is doing what the restless leg does, what the Tourette’s tic does: expressing a signal that cannot find its proper arc.

My dentist says the nerve in one of my teeth is inflamed and that the only remedy is a root canal. He also says it will probably still hurt after the procedure. He said this casually, as though it were a minor caveat. I think it is the most important thing he said.

I do not give medical or dental advice, and nothing here should be read as clinical guidance. I hold a PhD, not a medical degree. But the Myelin Mind has a precise account of what is happening in the trigeminal system when stress expresses itself through the jaw, and that account suggests that before any irreversible procedure, the right question is not how to remove the inflamed nerve, but why the nerve is inflamed and where the pain is actually living.

The trigeminal nerve is the largest of the twelve cranial nerves, carrying sensory information from the entire face, teeth, jaws, and sinuses to the brainstem. Its three branches, ophthalmic, maxillary, and mandibular, cover every surface of the face and the full architecture of the mouth. The peripheral branches of the trigeminal nerve are Schwann-cell myelinated, making dental pain a peripheral chiasm story in exactly the same way that phantom limb pain is a peripheral chiasm story. The trigeminal ganglion, sitting at the junction between the peripheral Schwann-cell myelination and the central oligodendrocyte myelination of the brainstem, is the DRG of the face: the point where the accumulated peripheral condition meets the central nervous system.

Bruxism is what happens when this system is chronically overloaded by stress. Under sustained stress, the amygdala, the brain’s threat detection centre, overactivates the mesencephalic trigeminal nucleus, which controls the masseter inhibitory reflex, the mechanism that ordinarily prevents the jaw from clenching with excessive force. When the mesocortical dopaminergic pathway, which connects the amygdala to the motor system through the nucleus accumbens, is destabilised by chronic cortisol elevation, the inhibitory reflex weakens and the trigeminal motor nucleus drives rhythmic jaw muscle activity without adequate contextual control.

The grinding is the trigeminal motor arc misfiring. The same family of mechanism as the Tourette’s tic and the restless leg: a signal arriving through the limbic-motor interface that cannot complete the intentional arc with adequate contextual meeting, expressing itself through the motor system instead. The jaw is the stress finding its way out through the only route available at three in the morning.

The inflamed dental nerve is the consequence of what the grinding does to the tooth. Sustained compression of the pulp, the soft tissue inside the tooth containing the nerve and blood supply, produces inflammation. Pulpal inflammation sends continuous, high-intensity signal up the trigeminal pathway. If that signal is sustained long enough, something happens that changes the nature of the problem entirely.

The trigeminal ganglion and the central trigeminal pathways begin to inscribe the pain signal in the accumulated myelinated condition. The background firing rate of the trigeminal neurons increases. Neurons in uninjured branches of the trigeminal nerve become sensitised through nitric oxide signalling from the inflamed branch. The pain that began as a peripheral event, a genuinely inflamed tooth nerve, acquires a central character. The accumulated myelinated condition has learned the pain. It is now generating it partly from its own interior, not only from the peripheral source.

This is central sensitisation, and it is what the dentist is describing, without using the term, when he says the tooth will probably still hurt after the root canal.

A root canal removes the peripheral dental nerve. It eliminates the source of the original signal. But if the accumulated myelinated condition of the trigeminal pathway has already inscribed the pain, removing the source does not reset the inscription. The central condition continues to generate the pain experience from its own interior, in the same way that the accumulated visual condition of a person with Charles Bonnet syndrome continues to generate vivid hallucinations after the retina has failed. The phantom tooth is as real a biological phenomenon as the phantom limb, and for the same reason: the accumulated peripheral-central condition does not simply switch off when the peripheral input is removed.

The literature confirms this with painful clarity. Among patients who sought dental treatment for what turned out to be trigeminal neuralgia, a condition in which the trigeminal nerve generates intense pain in the absence of any dental pathology, nearly nineteen percent reported that their pain worsened after the dental procedure. Multiple documented cases exist of patients who underwent root canal treatment on healthy teeth before trigeminal neuralgia was correctly diagnosed. Once the right diagnosis was made, anticonvulsant medication resolved the pain completely. The tooth had never been the problem. The myelinated pathway had been the problem all along.

The question worth asking before any irreversible dental procedure is not only whether the tooth is the source of the pain but whether the tooth is still the source of the pain, or whether the central inscription has already taken over.

There are clinical signs that point toward central sensitisation rather than simple peripheral pulpal inflammation. Pain that is continuous rather than triggered, pain that spreads beyond the original tooth, pain that is accompanied by burning or electric sensations, pain that has persisted for months without clear resolution, and, most significantly, a dentist’s own prediction that the pain will likely continue after treatment: these are signals that the accumulated myelinated condition is involved, and that removing the peripheral nerve will not resolve the situation.

An orofacial pain specialist, a neurologist with expertise in trigeminal pain, or an endodontist who is familiar with the post-traumatic trigeminal neuropathic pain literature is better placed to assess whether the problem is peripheral, central, or both, than a general dentist working from the assumption that an inflamed nerve requires removal.

The bruxism also requires its own attention, separately from the tooth. Grinding the teeth at night under chronic stress is the trigeminal motor system doing what it does when the accumulated condition cannot adequately contextualise the stress signal. Treating the tooth without treating the stress, without addressing the cortisol elevation that is destabilising the dopaminergic pathway and disinhibiting the trigeminal motor nucleus, is treating the consequence while the cause continues to grind, nightly, against whatever is not there.

Dentistry has an unusual relationship with the nervous system, unusual because it works on the peripheral endpoint of one of the most elaborately myelinated cranial nerves in the body, using procedures developed before the central sensitisation literature existed, under the assumption that removing a peripheral source of pain resolves the pain. In many cases it does. The tooth is infected, the nerve is acutely inflamed, the root canal removes the source and the pain resolves. That is a legitimate procedure with a legitimate evidence base.

But in cases where the pain has been sustained long enough for central sensitisation to develop, where the accumulated myelinated condition of the trigeminal pathway has already inscribed the signal and begun generating it from its own interior, the peripheral intervention treats the wrong end of the problem. The nerve is removed. The inscription remains.

My dentist’s casual admission that it will probably still hurt is not a minor caveat. It is a clinical signal that the accumulated myelinated condition may already have taken over. It deserves more investigation before the nerve is removed.

The jaw grinds because the stress has nowhere else to go. The tooth hurts because the jaw grinds. The pain may persist because the white matter has learned it. These are three separate problems, connected in sequence, each requiring a different intervention. A drill addresses only the middle one.

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