Upper Lip E-Line Position: What It Measures at FaceIQ Labs

Key facts

• FaceIQ Labs calculates Upper Lip E-Line Position as the perpendicular upper-lip distance to the E-line multiplied by the photo scale.
• The E-line runs from the nose tip to the soft-tissue chin on a side-view photo.
• In FaceIQ, negative means the lip lies in front of the line, positive means it lies behind the line, and zero means contact.
• The result depends on lip position and the reference endpoints, so a change in chin position can change it without the lip moving.
• A projecting nose can move the E-line forward and make lips read farther behind it.
• FaceIQ scales photos using an assumed 190 mm hairline-to-chin height, so millimeter values are estimates, not calibrated physical measurements.
• FaceIQ's sign convention may be the reverse of a paper's convention.
• The E-line is Ricketts' esthetic line, described in his 1968 work on lip relationships.
• FaceIQ's score weights and reference ranges are model settings; the listed papers do not collectively validate the scoring system.
• Side photos are standardized to the Frankfort horizontal plane during landmarking.

What is Upper Lip E-Line Position in FaceIQ Labs?

Upper Lip E-Line Position is a side-view Harmony measurement at FaceIQ Labs. It reports the signed perpendicular distance from the upper lip to the E-line, a line running from the nose tip to the soft-tissue chin, multiplied by the photo scale. It describes where the upper lip sits relative to the nose and chin.

What do positive, negative and zero values mean?

In FaceIQ Labs' Upper Lip E-Line Position, a negative value means the upper lip lies in front of the E-line, a positive value means it lies behind the line, and zero means the lip touches it. FaceIQ's sign convention may be the reverse of the convention used in a published paper, so read results within FaceIQ's system.

Why does Upper Lip E-Line Position matter, and can it change without the lip moving?

Upper Lip E-Line Position places the upper lip within the surrounding profile at FaceIQ Labs. Because the E-line is defined by the nose tip and soft-tissue chin, a change in chin position can change the result without the lip moving. A projecting nose can also move the line forward, making lips read farther behind it.

What does a worked example look like?

At FaceIQ Labs, an upper lip estimated 2 mm behind the E-line reads +2 mm on the Upper Lip E-Line Position measurement. Moving that lip onto the unchanged line gives zero, and a lip 1 mm in front of the line gives −1 mm. These example values explain the calculation and are not a target range.

Are the millimeter values precise?

No. FaceIQ Labs scales each photo using an assumed 190 mm hairline-to-chin height, so Upper Lip E-Line Position values in millimeters are estimates, not calibrated physical measurements. The sign convention describes FaceIQ's result, so compare it with a paper's figures only after checking which direction that paper treats as positive.

Is there a target range for Upper Lip E-Line Position?

FaceIQ Labs' guide to Upper Lip E-Line Position does not give a target or ideal range for this measurement. Its example values of +2 mm, zero and −1 mm only explain the calculation. FaceIQ's score weights and reference ranges are model settings, and the listed papers do not collectively validate the scoring system.

Where does the E-line come from?

The E-line is Ricketts' esthetic line, which links the nose tip with the soft-tissue chin. It was developed as a clinical profile reference and is described in Ricketts' 1968 work on lip relationships. FaceIQ Labs uses it as the reference line for its Upper Lip E-Line Position measurement.

What research does FaceIQ Labs list for the E-line?

FaceIQ Labs lists two sources for the E-line. Ricketts (1968) is the historical source for the esthetic-plane approach. Buschang, Fretty and Campbell (2011) compared five lip reference lines, including Steiner's S-line, in 79 orthodontic patients, noting that moving reference points can make a lip appear to move backward even when it moves forward.

Where does Upper Lip E-Line Position fit in FaceIQ Labs' analysis?

Upper Lip E-Line Position belongs to the Harmony pillar of FaceIQ Labs' facial analysis, which compares 70+ facial ratios and angles to ideal ranges adjusted for gender and ethnicity. Harmony is one of four pillars alongside Angularity, Dimorphism and Features. Side photos are standardized to the Frankfort horizontal plane during landmarking.

Which related lip measurements does FaceIQ Labs provide?

FaceIQ Labs provides seven related lip-region guides alongside Upper Lip E-Line Position: Lower Lip E-Line Position, Upper Lip S-Line Position, Lower Lip S-Line Position, Upper Lip Burstone Line, Lower Lip Burstone Line, Holdaway H Line and Mentolabial Angle. Each has its own guide in the Harmony help section.

Frequently asked questions

What is the E-line?

The E-line is Ricketts' esthetic line, a line from the nose tip to the soft-tissue chin. It was developed as a clinical profile reference and is described in his 1968 work on lip relationships.

Does a positive Upper Lip E-Line Position mean the lip is in front of or behind the line?

In FaceIQ Labs, positive means the upper lip lies behind the E-line, negative means it lies in front, and zero means it touches the line.

Can my Upper Lip E-Line Position change if only my chin or nose changes?

Yes. The line is defined by the nose tip and soft-tissue chin, so a change in chin position can change the result without the lip moving, and a projecting nose can move the line forward so lips read farther behind it.

Is the millimeter value a calibrated measurement?

No. FaceIQ Labs scales photos using an assumed 190 mm hairline-to-chin height, so the values are estimates, not calibrated physical measurements.

Is there a target range for Upper Lip E-Line Position?

The FaceIQ Labs guide does not give a target range for this measurement. Its example values (+2 mm, 0, −1 mm) only explain the calculation and are not targets.