Major landmarks on the mandible, or lower jaw bone, pertinent to Asian jaw reduction surgery include the body, ramus, and the area of junction between body and ramus known as the angle.

The masseter muscle attaches to the mandible over most of ramus extending all the way to the angle.

Patients with a relatively prominent or "square" jaw possess an angle that is more horizontal in its excursion and/or a ramus that is thicker and thus flared outward. A masseter muscle that is overly developed is sometimes said to be "hypertrophied."

Asian jawline reduction involves sculpting and reshaping of these main structural landmarks using surgical and non-surgical methods.

The maxilla, or upper jaw bone, unlies the midface and bears the upper teeth.