At what point do collateral ligaments become taut during jaw movement?

The tautness of the collateral ligaments during jaw movement is critical for understanding the mechanics of the temporomandibular joint (TMJ). During the end of the rotation phase of jaw movement, the condyle and the disc have moved into a position where the collaterals are pulled taut, providing essential stability to the joint as the jaw transitions from rotation to translation.

At this point, the lateral and medial collateral ligaments help to control side-to-side movements and limit excessive movement of the condyle, ensuring joint integrity during functional activities such as chewing. This stability is especially important during movements that involve the maximum load, such as during occlusion or heavy bite forces.

In comparison, other phases of jaw movement do not engage the collateral ligaments in the same manner. During the beginning of rotation phase, the ligaments are not fully strained, as the condyle has not yet reached a position that stretches them. During maximum opening, the ligaments are at their greatest length but are not necessarily taut; they provide flexibility to allow for a wide range of motion. Lastly, during the closing phase, the ligaments remain passive until the joint reaches a position where they may begin to engage again.

Thus, the end of the rotation phase