Which muscles are primarily involved in opening the mandible?

The primary muscles involved in opening the mandible are indeed the hyoids, digastric, and lateral pterygoid muscles. The lateral pterygoid muscle plays a critical role in depressing the mandible and allows for the mouth to open. This muscle provides the necessary movement to move the head of the mandible forward and downward, facilitating the jaw's opening.

The hyoid muscles, particularly the digastric and mylohyoid muscles, assist this action as they also help to lower the mandible. These muscles act in concert with the lateral pterygoid to effectively initiate and control the opening of the jaw.

While other muscles, like the masseter and temporalis, are responsible for closing the jaw and elevating the mandible, they do not contribute to the action of opening the mandible. Understanding the specific actions of these muscle groups is essential in both anatomy and clinical applications related to TMJ dysfunction and disorders.