Lip Length

Mean lip length is 23mm in males and 20mm in females and generally increases with age.¹¹ Lip length should be measured in repose from the sub-nasal to the most inferior visible portion of the upper lip at the midline. In a harmonious smile, lip length is nearly equivalent in length to commissure height. When an individual smiles, the commissures of the mouth move outward and upward and create an arched lip form. This shape is considered ideally esthetic. It should also be noted that decreased upper lip length can lead to lip incompetence, excessive gingival display, and/or a reverse resting upper lip line, which can all negatively impact perceived smile esthetics.²⁵