What is an Enlarged Jaw Muscle?
An enlarged masseter muscle means the masseter muscles at the back corners of your jaw have grown larger than usual.
Masseter enlargement can happen because of chronic teeth grinding, jaw clenching, stress, or genetics. For some people, it mostly changes facial shape. Others may feel discomfort or tightness from the overactive muscle. This muscle enlarges with repeated strenuous use, similar to how a bicep might get bigger after repeated bicep curls at the gym.

