Figure 2: (A and B) Rest position linear measurements. (a) upper lip length. (b) upper lip thickness. (c) interlabial gap. (d) outer intercommissural width. (e) commissural height. (C, D) Smile photograph linear measurements. (a) upper lip length. (b) upper lip thickness. (c) interlabial gap. (d) outer intercommissural width. (e) commissural height