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Animated Tutorial of the Temporomandibular System
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Non-working posterior inference causes non-working side joint and disc strain.    In the Class III scheme.
Upon engagement of a posterior interference following slight translation, the temporalis can maximize contraction intensity.

With the resistance to the ipsilateral LP being anterior, the strain provided is inconsequencial, as it braces the condyle against the eminance.  However, the superior head of the LP contracts simultaneously with the temporalis, thereby creating considerable compaction and strain to the disc and condylar head.


Above, the practitioner focuses on the canine rise, and may miss the contralateral posterior resistance.

 

 
Boyd Classification of Parafunction
2b: Unilateral posterior resistance;
Ipsilateral joint strain/load
How the Class III occlusal scheme allows joint strain in excursive movments
In the event there is a parafucntional excursive movement with the Class III occlusal scheme (in the absence of canine rise, which would thereby disclude the posterior teeth), one condyle translates, while the other pivots.  The loction of the resulting posterior contact dictates the potential activity of the superior belly(s) of the Lateral Pterygoid(s), and the strain/conpaction placed on the condyle/disc assembly.
Next: Comparing the NTI's occluding scheme with other occluding schemes.
1. Introduction of normal function versus parafunction
2. The simultaneous combination of condylar rotation and translation
3. Normal unilateral activity and effect of a Lateral Pterygoid muscle
4.  Parafunctional clenching activity of the Temporalis
5.  How various occlusal schemes alter Temporalis clenching intensity
6.  The maximum clenching intensity occurs in the musculoskeletally stable position
7. How "canine rise" serves to diffuse parafunction
8. Working posterior interference causes non-working side joint strain during occluding
9. Non-working posterior inference causes non-working side joint and disc strain,  and CLASS III complications
10. Comparing the NTI's occluding scheme with other occluding schemes.
11. How excess vertical dimension provided by the NTI can be straining to a joint
12. Clenching in a protrusive position can cause/perpetuate facial/sinus symptoms and cervical tension.
13. The  Parafunctional Nature of Articulators