As we age, the upper lip sags downwards due to the effects of gravity and decreased perioral muscle tone, reducing the visibility of the upper teeth when speaking or smiling, while the lower lip muscles relax, making the lower incisors more prominent; this creates an aged expression in facial aesthetics. In aesthetic rejuvenation treatments, this is compensated by lengthening and volumizing the upper incisors (especially their incisal edges) by 1-2 mm with laminate veneers or zirconium crowns. This mechanically supports the upper lip from behind, restoring the visibility of the upper teeth (smile window) to the proportions of youth, while pushing the dominant appearance of the lower teeth into the background, resulting in a more energetic and dynamic facial profile.
