What occurs during the closing phase of the jaw movement?

During the closing phase of jaw movement, the primary action is the elevation of the mandible. This process involves the muscles responsible for closing the jaw, predominantly the masseter and temporalis muscles, which contract to lift the mandible up towards the maxilla (upper jaw).

Elevation is crucial for functions such as chewing and biting, allowing the teeth to make contact and effectively grind food. Understanding this mechanism is vital in TMJ practice, as dysfunction in the muscles involved in elevation can lead to difficulties and pain in closing the jaw properly.

The other movements described, such as depression, protrusion, and lateral movement, pertain to other phases of jaw mechanics. Depression refers to opening the jaw, protrusion involves moving the mandible forward, and lateral movement describes the side-to-side actions that can occur during chewing. Each of these movements serves distinct functions in the overall mechanics of the jaw, but they are not part of the closing phase.