The patient/client is sitting (or standing) and either facing a mirror or facing the person who will demonstrate clenching the teeth. After showing a picture or demonstrating this motion, ask the patient/client to clench the teeth. With permission and either clean hands or gloves, gently place one or two fingers on the inside of the mouth, deep to the cheek. Keep your finger out of the path of the closing teeth or block the attempt to contact the teeth with an object, such as a cork. With the muscle relaxed initially, ask the patient/client to clench the teeth, then relax and repeat this motion if necessary. If permission is not granted, then observe as the person clenches the teeth, relaxes and then repeats this motion if necessary. While you are not able to observe the muscle contraction, you can assess ability to clench the teeth and the symmetry of jaw closing, knowing that other muscles are involved in this action.

Many people can not reliably distinguish the lateral pterygoid from the medial pterygoid, even though the actions on the temporomandibular joint are opposite.

Palpation of this muscle can not be demonstrated by video from the outer aspect of the face as the muscle is palpated on the inside of the mouth. There is no audio pronunciation for this structure.