Final answer:
To assist with a medical procedure, tilt the head back and pull the lower jaw forward by activating the masseter and temporalis muscles.
Step-by-step explanation:
To tilt the head back and pull the lower jaw forward to assist with a medical procedure, you can use the muscles involved in mandible protraction and retraction.
Protraction of the mandible occurs when you push your lower jaw forward, while retraction pulls it backward.
The main muscle used for this movement is the masseter muscle, which elevates the mandible to close the mouth. It is assisted by the temporalis muscle, which retracts the mandible.
By activating these muscles, you can tilt your head back and pull your lower jaw forward.