The GNM Convergence Pilot Study is an OcclusionConnections (OC) community effort to compile, in one place, what many of us have observed in our own practices for years: that GNM orthotic treatment moves a patient’s K7 measurements toward physiologic norms, and that those measurable changes track with how the patient actually feels.
OC dentists are beginning to compile their cases, treated according to the OC GNM teachings and orthotic adjustment protocols. This page presents the initial findings from the first 14 cases.
The clinical use of computerized mandibular tracking, electromyography, and joint vibration analysis in TMD diagnosis and treatment has been challenged in the published literature, most prominently by Manfredini and colleagues, who have questioned whether these instrumented measurements reliably distinguish disease states or detect treatment-related change. Cooper and Adib responded with methodological critiques of those studies in 2014, but the broader skeptical position has continued to be cited in TMD literature.
Much of what the neuromuscular and GNM community knows sits inside individual practices — in private files, charts, and decades of careful clinical judgment that has never been assembled anywhere outside our own offices. The intent of this pilot is to begin getting those observations into a durable, shared form before that knowledge is lost.
We use the term “convergence” to describe what we see clinically: when treatment is working, the separate K7 channels tend to move together toward a physiologic norm rather than drifting independently. The pilot is built to document whether that pattern holds up when the data is actually counted. It is framed as a question to examine honestly, not a conclusion to confirm.
For every case, four K7 channels are recorded before treatment and after, each paired with the patient’s own symptom scores:
| Channel | What it reads |
|---|---|
| Scan 2 / Scan 7 | Sagittal trajectory and AV ratio (before = Scan 2 in the habitual bite; after = Scan 7 with the GNM orthotic in) |
| Scan 9 | Resting EMG, eight channels |
| Scan 11 | Functional clench EMG — natural clench and cotton-roll clench |
| Scan 15 | ESG joint sounds |
| Patient Subjective Summary | Each symptom self-scored 0–5 (5 = severe), totalled |
| Measure | Before → after |
|---|---|
| Patient symptom scores | Lower in all 14 cases; median reduction 85%. One case changed very little (−2%). |
| Resting EMG (Scan 9) | Moved toward the OC normative values in 12 of 14 |
| Natural clench (Scan 11) | Moved toward the 250 µV norm in 12 of 14 |
| Recruitment gap (Scan 11) | Narrowed in 9 of 14 |
| Joint sounds (Scan 15) | Normal joint sounds (quiet, or low-amplitude soft-tissue sounds below 300 Hz) in 4 of 14 before treatment, and 12 of 14 after. 10 cases had pathologic high-frequency (>300 Hz) sounds before; 8 of them no longer did after (4 quiet, 4 soft tissue only). |
| AV ratio (Scan 2 / 7) | Group average 0.55 → 0.63 (see below); individual cases vary |
| Closing velocity (supplementary, 10 cases) | All 5 that began below 250 mm/s reached 250+; the other 5 were 250+ before and after |
Cases where a channel did not move are shown the same as cases where it did. They are part of what the pilot is meant to examine.
The AV ratio expresses the opening path as anterior-posterior movement over vertical movement. In the GNM framework, 0.618 — the golden proportion — is the harmonic reference, corresponding to a path about 58° from the occlusal plane. Each patient’s physiologic AV ratio is read in the context of their own skeletal architecture, so 0.618 is a reference, not a pass/fail line.
The compiled data are offered as clinical documentation, not as a controlled study. They neither prove that GNM orthotic therapy is uniquely effective nor that the K7 is a perfect diagnostic instrument.
This work doesn’t claim to meet methodological standards no one else meets, or even to meet the standards critics demand. It claims something simpler and more empirical: we measure things others don’t measure. We document what we measure. We compile that documentation across OC practices. We make it publicly accessible. We name our limitations honestly. We invite the field to engage with the data on its merits.
Limitations we name plainly:
The first step is simply to compile the cases honestly and see what they tell us. This page will be updated as more OC dentists contribute cases. How the study works and how to contribute a case: the study protocol. OC dentists who would like to take part can contact Dr. Clayton Chan at: clayton@drclaytonchan.com.