E-Line.

What the E-line is

The E-line — short for “Esthetic line” — was defined by American orthodontist Robert Ricketts in 1957 as a clinical tool for evaluating side-profile balance. It is a single straight line drawn from:

• Pronasale — the most projected point of your nose tip
• Pogonion — the most projected point of your chin

Drop a ruler against your side profile and connect those two points. That’s your E-line. Where your lips sit relative to that line tells you a lot about your side profile.

The ideal E-line position

Ricketts’ original measurements, still the standard reference:

• Upper lip: sits ~4 mm behind the E-line
• Lower lip: sits ~2 mm behind the E-line

So both lips should be behind the line, with the upper lip slightly more recessed than the lower lip. The whole lip area should be tucked just inside the nose-to-chin span, not pushing out into it.

When that’s the case, your side profile looks balanced — the nose-to-chin diagonal is clean, no lip pushing through it. When the lips push past the line, the profile reads as protrusive (often called “bimaxillary protrusion”). When the lips sit too far behind the line, the profile reads as recessed — usually because the chin is over-projected or the nose is too long.

What E-line position tells you

Four common patterns:

1. Lips behind the line, balanced — Ricketts ideal. ~50% of orthodontic patients.
2. Lips on or in front of the line — bimaxillary protrusion. Common in some ethnic profiles; can be reduced with orthodontic extraction or jaw surgery.
3. Lips far behind the line, weak chin — often a neotenous profile. Genioplasty (chin augmentation) is the common fix.
4. Lips far behind the line, long nose — the “Roman” or “aquiline” profile. The lips aren’t actually recessed; the nose is just pushing the line out.

The same lip position can be “ideal” or “protrusive” depending on what your nose and chin are doing. This is why side-profile evaluation is fundamentally relational — you can’t grade a lip in isolation.

E-line and ethnic variation

The original Ricketts measurements were taken on a Caucasian population. Reference values shift by ethnicity:

• East Asian populations average ~1–2 mm more forward lip position
• Black populations average ~3–4 mm more forward lip position
• South Asian populations track close to the Caucasian baseline

A face that’s “protrusive” by Ricketts numbers may be perfectly balanced by population-specific norms. Modern orthodontic practice uses ethnicity-adjusted E-line targets, and Fazly’s scan does the same — the app doesn’t penalize a Black or East Asian profile for sitting forward on the Ricketts scale.

How it relates to the golden ratio and ogee curve

The E-line is one of several side-profile aesthetic rules:

• The golden ratio governs vertical proportions (forehead, midface, lower face thirds)
• The ogee curve governs the S-curve from cheekbone to jaw
• The E-line governs the nose-lip-chin diagonal

All three need to work together for a “clean” side profile. A face can hit golden-ratio thirds perfectly and still look off because the E-line is wrong — and vice versa.

How to fix a poor E-line

Soft-tissue fixes (no surgery):

• Lip protrusive — lip exercises and posture won’t fix bimaxillary protrusion; lip filler dissolution can help if filler is causing it
• Weak chin — chin filler or genioplasty (the surgical option)
• Long nose — rhinoplasty
• Heavy upper lip from filler migration — dissolve, reset

Orthodontic fixes (over 1–2 years):

• Premolar extraction + orthodontic retraction — pulls protrusive lips back ~3–5 mm. Standard fix for bimaxillary protrusion.
• Distalization — moves teeth back without extraction; less retraction but less invasive

What Fazly does

The scan estimates your E-line from the side-profile photo and reports lip position in mm behind/in front of the line, adjusted for the closest ethnic baseline. It flags whether the issue (if any) is the lips, the chin, or the nose — the same “lips 2 mm forward of E-line” reading is a fixable lip problem on one face and a fundamental chin-deficiency problem on another, and Fazly tells you which.

Take side-profile scans with your head level (Frankfurt plane), camera at eye height, and a neutral lip seal — that’s the only condition where E-line readings are stable.