Forces resisting jaw displacement in relaxed humans: a predominantly viscous phenomenon
Bibliographic record
Abstract
Forces opening the relaxed human jaw are resisted by intrinsic restraints, including passive tensions in the jaw-closing muscles. These muscle tensions have been modelled as viscoelastic elements, and static measurements suggest their elastic portions contribute approximately a total of 5 N resistance at wide gape. As the viscous damping properties of muscles which affect the jaw's dynamic behaviour are unknown, we measured the jaw opening force required to reach maximum gape during fast and slow opening in six relaxed subjects. These data were then incorporated in a dynamic mathematical jaw model to determine the damping properties of the masticatory system. During the 3 and 8 s opening trials, forces increased with gape (6.7 +/- 3.3 and 3.9 +/- 2.3 N, respectively, at 50% gape) and reached their maxima at wide gape (19.9 +/- 4.5 and 13.2 +/- 4.4 N, respectively). The muscle damping constant needed by the model to emulate these results was 150 Nsm(-1), approximately 25% lower than the calculated critical damping constant. This study suggests low forces are required to open the jaw in relaxed humans, and that jaw viscosity, not elasticity, provides the major resistance to motion.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".