Upon closing, what role does the lateral pterygoid play in mandibular movement?

The lateral pterygoid muscle plays a crucial role in mandibular movement, particularly during the opening of the jaw rather than its closure. This muscle is unique among the masticatory muscles because it is primarily responsible for the depression (opening) of the mandible. It also contributes to the forward and lateral movements of the jaw during chewing.

While the muscles responsible for the closure of the mandible are predominantly the masseter and temporalis, the lateral pterygoid's contraction facilitates the initial movement needed for the jaw to open. During mastication, the lateral pterygoid works in conjunction with these other muscles, but its primary role is to allow for the opening and some degree of lateral movement of the mandible, not for closing it.

Therefore, understanding the lateral pterygoid's function underscores its importance in the overall mechanics of jaw movement, especially in how it assists in the opening process rather than being associated primarily with closing the mandible.