FORMA FEATURE / CHIN & JAWJaw angle: measurements, ratios, and research
The gonial region is where the ascending ramus meets the mandibular body. A surface-photo angle is not interchangeable with an X-ray skeletal gonial angle. This page separates published measurements from interpretation, preference experiments, and community speculation.
What jaw angle means
In a true profile, estimate the angle between posterior ramus and lower mandibular-border tangents. Soft tissue obscures both lines; do not read it from a three-quarter portrait.
Facial measurements only become comparable when the view, head position, soft-tissue landmarks, and endpoint definitions are held constant. A number copied from a profile photograph is not interchangeable with a value measured from a clinical scan or a front-facing portrait.
Official measurements, ratios & competing claims
130° Preferred in a published male-jaw survey
An Internet survey using photographs preferred a 130° profile jaw angle.
Study: A single survey using simplified, unbalanced rating scales, designed to inform implant contours; not a universal anatomical target. The ideal male jaw angle—An Internet survey
115–120° A sharper forum preference
One forum post lists 115–120° as its preferred range. Another guide gives 115–130°.
Forum claim: No controlled raters, standardized measurement, or validated outcome. The disagreement is itself a reason not to treat a forum interval as settled evidence. In-depth ratio discussion
Practical takeaway
Prioritize a clear corner within the whole jaw outline.
The published survey provides a concrete angle preference. Compare it with ramus slope and mandibular-body slope before using the sharper forum ranges.
What changes the answer
The corner angle is formed by two directions: changing either can produce the same number. Soft tissue and head rotation can hide the corner even when the underlying geometry is angular.
Use these ranges to ask a better question about proportion—not to grade a face or choose a procedure by number alone. A qualified clinician still needs to examine function, tissue, skeletal structure, and your goals in person.
Connected facial features
Read or start jaw angle discussions · Explore the interactive atlas