E-line

The E-line, or Ricketts' aesthetic line, is a straight line drawn in profile from the tip of the nose to the most projected point of the chin. It is named after the orthodontist Robert Ricketts, who proposed it in the 1950s as a way to judge whether the lips sit in balance with the nose and chin. The convention places the upper lip roughly four millimetres behind the line and the lower lip roughly two millimetres behind it, though the figures differ by ancestry and by the reference population a given textbook used. Orthodontists use it as one input when deciding whether a case needs jaw surgery, lip treatment or nothing at all. It cannot be measured from a front-facing photograph, which is why this site does not offer a tool for it: the E-line is a profile measurement and needs a profile.