Thin Lips

Thin lips describe a naturally smaller lip volume, often combined with a less defined vermilion border, a shorter philtrum or a flat Cupid's bow. The lips are made of skin and mucosa over a fibrous and muscular layer (primarily the orbicularis oris). Their shape is determined by bone structure beneath, by the balance of soft tissue between upper and lower, and by the elasticity of the surrounding skin. Lips thin with age because the tissue volume gradually decreases, the perioral skin develops fine rhytides, and the philtral columns flatten. Some patients also present with thin lips throughout life, simply as a genetic feature rather than an age-related change. Several factors influence how visible lip thinness becomes. Sun damage accelerates the development of perioral vertical lines, often called smoker's lines or barcode lines, which make the lip border look less crisp even when the lip volume is preserved. Smoking produces both dermal damage and repeated contraction of the orbicularis oris, deepening perioral lines and shortening the lip. Tooth position and dental changes in middle age (wear, recession, loss of molars) subtly reduce the anterior support of the lip and make it appear flatter. Previous oral surgery or cleft repair can leave scarring that limits how the lip responds to treatment. The mainstay of treatment is hyaluronic-acid lip fillers. Modern products come in a range of viscosities, from very soft gels that hydrate and subtly define the lip border without adding bulk, through to slightly firmer gels that can lengthen the philtral columns or project the lip forward. The right product and technique depends on what the patient actually wants: a soft natural enhancement, better definition of the Cupid's bow, correction of asymmetry, or specific restoration of an aged lip to its earlier shape. Good injectors use small volumes at a time, build over several sessions rather than injecting a large volume at once, and discuss proportions between upper and lower lip openly. Dermal fillers of slightly firmer grades are occasionally used in the perioral area (for example in the philtral columns, or for support at the oral commissures) to complement the lip work itself. Patients with a history of severe cold sores, active oral infection, autoimmune conditions affecting the mucosa, or previous lip surgery should be assessed carefully. Anyone under 18 cannot receive lip fillers in the UK regardless of consent.