Which muscle acts as a synergist to mandible elevation?

The pterygoid muscle, specifically the medial pterygoid, acts as a synergist in the elevation of the mandible. Its primary role is to assist in this action alongside the masseter and temporalis muscles, which are the main muscles responsible for elevating the jaw. The medial pterygoid originates from the pterygoid plates of the sphenoid bone and attaches to the mandible, allowing it to effectively contribute to the elevation and closing of the jaw during activities such as chewing.

In contrast, the other muscles listed do not primarily function as synergists for mandible elevation. The pectineus is primarily involved in hip adduction and flexion, while the mylohyoid and digastric muscles are more associated with the depression of the mandible and swallowing actions rather than elevation. The mylohyoid contributes to the floor of the mouth and assists in depressing the mandible, while the digastric muscle primarily aids in lowering the mandible due to its two muscle bellies that pull it downward when contracted.