27 Lip Rejuvenation
The upper and lower lips respond differently to cosmetic procedures.
Many facial structures are involved with perioral aging.
Skin resurfacing techniques, lip augmentation procedures, nasal base resection, and vermilion advancement are often combined to achieve perioral rejuvenation.
Few other structures of the face carry such an important functional and aesthetic value as the lips. For thousands of years, the physical shape of the lips has had significant aesthetic connotations. Full lips are associated with beauty, fertility, health, and youth. Thin lips are associated with weakness, aging, and fragility. Even the fullest lips, however, will be subject to the many varied effects of the aging process in this anatomical region, resulting in loss of proportion and involution. Because of the special aesthetic and functional features of the lips, surgical rejuvenation of this area tests the skills of even the most experienced surgeons.
Many patients begin the consultation regarding lip rejuvenation with trepidation, for fear of receiving large unnatural features. Other patients may seek out cosmetic surgeons who prefer a more overdone or inflated look. It is important to discuss the patient′s goals and determine if the goals are consistent with your aesthetic preferences. If the goals are not in agreement, the surgeon may elect not to operate on the patient. The patient′s threshold for recovery, acceptance of possible complications, and realistic expectations are additional factors to evaluate.
Background: Basic Science of Procedure
The lip is not only an important aesthetic feature of the face, but also a very dynamic functional structure. Lip movements are an important element of speech, eating, digestion, and romance. Cosmetic alteration of the lips should therefore ideally seek to have minimal alteration of lip motion. When determining a treatment course, it is important to consider that the choice of procedures, combined with the patient′s healing, may result in temporary, or rarely, permanent alteration of lip function.
The ideal lower third of the face extends from the nasal base to the inferior aspect of the chin. It can be further subdivided into an upper third, extending from the nasal base to the inferior aspect of the upper lip vermilion, and a lower two-thirds extending from the superior aspect of the lower lip vermilion down to the inferior aspect of the chin. The lateral view should reveal a gentle curve from the nasal base to the upper lip vermilion. The lips should have a slightly rounded contour when viewed from the side. This feature is commonly called the projection of the lips ( Fig. 27.1 ).
Aesthetically, there is no ideal lip proportion relative to upper and lower lip projection. That is, some patients have a fuller lower lip than upper lip, others may be balanced, and some may have a fuller upper lip. Variations in the position of the underlying teeth, bone structure, and lip anatomy account for the multitude of lip variations.
The lip derives its unique shape from the fact that the upper lip forms from three subunits when viewed from the front. The condensation of these components results in a structure defined by two raised philtral ridges flowing from the nasal base to the vermilion-cutaneous junction. The ridges, combined with a central depression, the philtral sulcus, create the defining feature of the upper lip, known as the cupid′s bow.1–3
The embryology of the lower lip is very different from the upper lip. The lower lip forms from two subunits that merge together, resulting in a smooth lip border ( Fig. 27.2 ). The embryological differences result in two very different structures in regard to movement and response to surgical procedures. The upper lip flexes much more than the lower lip; therefore, it is less tolerant of lip procedures that restrict movement. Surrounding the lip vermilion-cutaneous junction is a raised non-hair-bearing white roll. This structure, originally described by Gilles and Kilner,4 is believed to act as a reservoir of elastic elements that allow the lips the flexibility to perform their many actions.
The bulk of the lip is composed of a sphincteric muscle, the orbicularis oris, covered by a thin mucosal layer. The orbicularis muscle condenses at the corner of the mouth into a modiolus. A few superficial fibers of the orbicularis muscle insert directly into the undersurface of the dermis. The depresso anguli oris is a small muscle that runs from the modiolus to the mandible; its path becomes more apparent with age due to frequent frowning. Both upper and lower lips act like curtains draped over the underlying teeth. Therefore, evaluation of the patient′s occlusion and tooth size is an important part of the pretreatment examination.r
The pink, or vermilion, portion of the lip is divided into a dry and wet surface separated by the “wet line” ( Fig. 27.3 ). The dry vermilion is exposed to the air, and the wet vermilion is bathed by oral secretions. After lip rejuvenation, commonly a small portion of the wet vermilion may be exposed to the air and remain dry and flaky until it has an opportunity to adapt to its new position.
As the lips age, the cutaneous portion of the lips may develop actinic changes, such as thickening of the epidermis and lentigines. With repeated pursing of the lips, vertical and horizontal rhytids begin to appear. Philtral ridges and white rolls begin to flatten as the collagen breaks down, resulting in a longer upper and lower lip. As the upper lip lengthens, the ability to see the inferior aspect of the upper incisors disappears.
Lip volume, which peaked at puberty, begins to deflate. Therefore, the once full vermilion of the lips extending from commissure to commissure begins to shorten, losing the outer corners first, followed by loss of central volume. The amount of lip vermilion show begins to decrease as the lips lose volume and the white roll flattens. Rhytids begin to develop in the vermilion portion of the lip. As the vermilion portion of the lip loses volume, the cutaneous portion is generally losing volume from a decrease in subcutaneous fat and orbicularis muscle mass. This will commonly deepen the horizontal lines across the central upper lip and vertical lines surrounding the lips. Often the teeth, which have helped support and add projection to the lips, begin to decrease in vertical height, move, and turn inward. The supporting maxillary and mandibular bone also loses volume, contributing to the involution of the lower third of the face with age.
Repeated action of the depressor anguli oris, a small muscle at the corner of the mouth, combined with loss of soft tissue volume, results in a downturning of the lip corners. As this process occurs, the smooth jaw line of youth is erased and replaced with a wide, irregular jaw line ( Fig. 27.4 ).
Patients undergoing lip procedures should have realistic expectations. Physical examination involves an assessment of the overall proportions of the face, length of the upper and lower lip, definition of the lip structures, lip projection, amount of vermilion show on frontal and lateral views, quality of cutaneous and vermilion skin, amount of dental show, occlusion, and tooth appearance.
Technical Aspects of Procedure
Lip rejuvenation procedures are divided into four categories based on the patient′s anatomy.
Rejuvenation of the perioral and vermilion skin
Autogenous, hyaluronic acid (HA)
Autologous fat transfer
Acellular human dermal matrix
Long upper lip with adequate cupid′s bow definition—nasal base resection
Long upper lip with poor cupid′s bow definition—vermilion advancement
The first section touches on the importance of the quality of the overlying skin when rejuvenating the lip area. The next sections transition into structural changes that occur with the aging process. To achieve the desired lip rejuvenation, the cosmetic surgeon will often perform several lip procedures simultaneously.
Lip Anesthesia/Patient Preparation
There are a variety of topical anesthetics currently available to apply to the cutaneous or vermilion lip. Care should be taken to check the patient′s history of medication allergies. Choose topical anesthetic agents that will not interact with the patient′s medications and have a low incidence of adverse reactions. Patients with a history of herpes simplex should receive systemic antiviral agents in the periprocedure period.
Topical anesthesia can be further supplemented with topical ice, held directly on the lip until the lip is adequately chilled. With the advent of fillers containing lidocaine, the use of regional blocks has ceased in the author′s practice, though the blocks do continue to be utilized in other practices. The very nervous patient could be placed on an anxiolytic agent and/or oral pain medication, to help make the procedure a more comfortable experience.
Excision techniques require the injection of a local anesthetic with epinephrine, mixed with hyaluronidase, to help minimize tissue distortion. If a HA filler is present or placed simultaneously, or if an acellular dermal matrix graft is used, hyaluronidase should not be used.
If a patient has a history of herpes simplex, then systemic antiviral treatment is initiated prior to the procedure.
Rejuvenation of the Perioral and Vermilion Skin
The perioral skin aesthetic unit tends to be prone to rhytid formation due to the frequent muscle action of the area. Patients display a reactive thickening of the epidermis in response to years of sun and wind damage. Smoking also affects the appearance of the lips and leads to increased risks in any lip rejuvenation procedure. Nightly application of topical retinoids, coupled with daily use of sun protection, is often the first step in softening these actinic changes. As the aging process continues and exposure to environmental factors and lip pursing activities occur, perioral lines develop. In-office treatments for the perioral lines involve the use of botulinum toxin, fillers, and chemical peels.
Technical Aspects of Procedure—Botulinum Toxin Type A
Botulinum toxin type A is commonly used for the treatment of mild perioral rhytids, though it should be noted that this is a U.S. Food and Drug Administration (FDA) off-label use. It is important to understand the different types of botulinum toxins and use their appropriate doses. Generally, if onabotulinum toxin is used, 1 to 2 units are placed in the center of each lip rhytid. The technique involves placing the toxin immediately underneath the dermis in the middle of the wrinkle with a 30-gauge needle ( Fig. 27.5 ). If treating a downturning corner of the mouth, 2 units of botulinum toxin can be placed 1 cm lateral and 1 cm inferior to the oral commissure. Injecting medial to this point or along the mandibular edge should be avoided to minimize affecting the depressor labii inferioris. Inadvertent action of botulinum toxin on this muscle will cause the lower lip to rise up on that side. Patients should be advised that lip sphincter function may be affected, and the procedure should be avoided if this cannot be tolerated.