When is the articular capsule of TMJ most taut?

The articular capsule of the temporomandibular joint (TMJ) is most taut at the end of opening. This tautness occurs because, as the mandible opens, the condyle moves downward and forward along the articular eminence, which increases the tension in the capsule. By the time the mouth has opened fully, the capsule is stretched to its limit to accommodate the position of the joint and the movement of the mandible.

Understanding the mechanics of the TMJ is crucial, as different movements induce varying levels of tension in the joint structures. During mandibular retrusion, for instance, the articular capsule would not be as taut since the jaw is moving backward rather than down and away from its closed position. Similarly, at the start of opening, the movement has not yet progressed enough to create significant tension. When the jaw is fully closed, the elements of the joint are compressed, but the capsule is not under the same degree of strain as it is when the jaw is maximally opened.