Lip Augmentation

Cosmetic lip augmentation consists of the enlargement and reshaping of otherwise normal lips to improve their dimensional relation with the patient's nose, teeth, and surrounding facial structures. The appearance of the lips is determined by the spatial relation of the lip structures with the teeth in a 3-dimensional space and by their function during animation and speech.

According to a study by Popenko et al, which sought to establish the most attractive lip measurements in white women by using focus groups to evaluate facial images, the dimensions judged to have the greatest attractiveness included a lip surface area making up 9.6% of the lower third of the face and an upper/lower lip ratio of 1:2.[1]

For information on other lip procedures, see Medscape Reference articles Lip Reduction and Lip Reconstruction Procedures.

Lip augmentation has been described at least as far back as the early 20th century. Miller describes a procedure to evert the lip with multiple small incisions, giving it the appearance of increased size.[2]

Women of all ethnic and social backgrounds have applied cosmetics to their lips to define or alter their appearance since the Stone Age. Tribal ceremonies involving the introduction of various materials in the upper and lower lip to alter their shape, usually with the intent to enlarge them, have been practiced in African tribes for centuries.

Cosmetic lip augmentation is defined as the procedure designed to augment and improve the shape a lip that is not affected by trauma or congenital deformity. Typically, the upper lip is treated more frequently and to a greater degree than the lower lip.

Cosmetic deformities of the lips include both congenital and acquired etiologies. Some patients never develop adequate fullness in the lips; others develop atrophy of the soft tissue of the lips as they age.

Cosmetic indications refer to lip size and shape.

An accurate physical examination determines the specific area of deficiency or desired enhancement. Specifically, evaluate the patient's occlusion, maxillary-mandibular relations, and aging pattern. A general evaluation of the relation between the upper lip and the incisors reveals the appropriate course of action. Dr Bahaman Guyurion summarized the following algorithm approach to physical evaluation prior to lip augmentation:

• Optimal incisor show - Conservative augmentation by fat transfer or dermis fat graft

• Excessive incisor show - Augmentation by fat transfer or dermis fat graft

• Inadequate incisor show, long lip - Lip shortening and lift with incision at nasal base ("buffalo horn") in young patients with acute columella-labial angle or incision at vermillion border in older patients with perioral rhytids

• Inadequate incisor show, normal lip length - Maxillary lengthening with possible lip augmentation

Cosmetic indications include patients who desire a fuller or more shapely upper or lower lip and who are otherwise in good health.

Lip augmentation (see the image below) consists of the reshaping and/or enlargement of the visible portion of the lip, the vermillion. Alteration of the shape of the Cupid's bow and of the relation between the vermillion and the skin underlying the nasal columella also fall within the category of lip augmentation.

The upper lip extends from the base of the nose superiorly to the nasolabial folds laterally and to the free edge of the vermilion border inferiorly. The lower lip extends from the superior free vermilion edge superiorly, to the commissures laterally, and to the mandible inferiorly. Around the circumferential vermilion-skin border, a fine line of pale skin accentuates the color difference between the vermilion and normal skin. For more information about the relevant anatomy, see Lips and Perioral Region Anatomy.

Also important is to consider the relationship between lip height and incisor show in the anatomic analysis. Evaluate possible maxillary hypoplasia and protrusion and consider the patient's occlusion status.

Contraindications for cosmetic lip augmentation include facial nerve disorders, recurrent herpes simplex lesions, diabetes, severe hypertension, history of multiple allergies, and/or autoimmune disorders.

Various nonsurgical and temporary applications can plump the lips.[3] These topical applications usually work by causing a mild inflammatory response of the lip mucosa. They usually contain Capsicum annuum or Capsicum frutescens (the fruit of the red pepper plant, used for making cayenne pepper or Tabasco), although some may contain cinnamon oil or caffeine. Newer formulations contain palmitoyl oligopeptide and L-arginine for collagen synthesis.

Surgical lip augmentation can be achieved with injectable fillers, implants, and surgical advancement, roll, or lift.[4]

Injectable fillers

Lip augmentation with the use of injectable fillers obtains quick results with minimal downtime and repeatable applications.[5, 6, 7]

Lip augmentation with collagen and other fillers can be performed by injecting the material in any or all of the anatomic parts of the lip, allowing for a very controlled and predictable result. Precautions regarding mode of injection and quantity of the substance injected vary widely within this family of products.

Materials and products that have been used commonly overseas include hyaluronic acid preparations such as Restylane and Perlane. Restylane was approved by the US Food and Drug Administration (FDA) for lip augmentation in October 2011. Another hyaluronic acid, Juvéderm Ulta XC, received FDA approval for lip augmentation in 2015.[8, 9, 10]

When injecting filler composed of small-particle hyaluronic acid gel plus lidocaine for lip augmentation and perioral rhytid improvement, a multicenter, open-label, prospective study by Chopra et al indicated that a blunt-tipped microcannula can safely and effectively be substituted for a needle. There were no reports of serious adverse events in the study, and the Global Aesthetic Improvement and Medicis Lip Fullness scales showed clinically significant rates of lip improvement.[11]

A study by Rho et al indicated that hyaluronic acid fillers with intermediate cross-link density can produce a more pronounced upper lip augmentation than can lightly cross-linked hyaluronic acid. Specifically, the intermediate cross-link density filler used in the report was associated with a greater reduction in the columella–labial angle (CLA) than was the lightly cross-linked compound employed. In patients who received the filler with lighter cross-linking, the CLA changed from a mean pretreatment value of 104.4° to 102.8° at 12 weeks, while in individuals who were injected with the intermediate cross-link density filler, the angles were 103.2° and 96.3°, respectively.[12]

Autologous fat has gained increased popularity as a filler. The distinct advantage of fat as a volume augmenter is that the results obtained are long-lasting (in some cases, permanent), depending on the amount of tissue injected and the location treated. Moreover, the risk of allergic reactions is avoided since the fat used is autologous tissue. Fat is obtained from the patient's donor site under local anesthesia; prepared with saline wash, decantation, or centrifugation; and then injected in the lips. As much as 30% of the injected fat can persist after transplantation with appropriate technique, and, in some patients, almost complete survival of the graft has been reported. Lip augmentation with autologous tissue is a viable alternative to injectables and can produce durable long-term results.[13]

Taking into account the typical pattern of the labial arteries, Tansatit et al reported that superficial filler injection can be safely performed in the vermilion borders of the upper and lower lips, as well as in all parts of the lower lip. Upper lip injection should be to the middle body, according to the investigators, in order to avoid injuring the anastomotic arch of the superior labial arteries.[14]

Implants

Synthetic materials such as Gore-Tex/PTFE have been used successfully and allow for a controlled application with ease of use. Expanded tetrafluoroethylene is available in tubes with diameters of 2.4 mm and 3.4 mm. They are applied with a disposable applicator and implanted in the subdermal plane at the vermillion border.

Biologic materials are available commercially in the United States and consist of decellularized dermal matrix products. AlloDerm is a harvested dermis that is prepared through a proprietary process and is available for implantation.[15] Other materials, such as porcine submucosa (Surgisis), provide a nonreactive basis for native tissue integration in the lip.[16] Various reports are available, indicating that the decellularized dermis becomes a scaffolding for neovascular ingrowth, and full integration in the patient's tissues has been verified experimentally. While these materials may have additional costs, they are available off the shelf and avoid both donor site morbidity and the use of prosthetic materials.

Autologous dermis, dermal fat, tendon, and fascia grafts are obtained from the patient, shaped, and implanted.[17] In some patients, the grafts may be obtained from skin resected during local procedures such as lip lift or advancement, de-epithelialized, and then grafted. Once the tissue is harvested and shaped, it is threaded through a tunnel within the lip. A curved tendon passer facilitates this procedure. They provide a natural autologous option for both primary and revisional lip augmentation.[18]

A study by Tabrizi et al of 15 patients supported the use of dermal fat grafting as an effective treatment for thin lips, finding significant improvements in vermilion show (mean change 1.73 mm) and upper lip projection (mean change 2.33 mm) 12 months after the procedure. No serious complications occurred during the study.[19]

Surgical procedures

Surgical procedures involving advancement, lift, and roll are designed to enhance various parts of the lip anatomy using the patient's local tissues. Z-plasty, V-Y, and W advancement flaps are intended to project and fill the central and lateral parts of the vermillion.[20, 21, 22] The flaps are designed on the oral-wet vermillion-mucosal aspect of the lip and dissected just superficial to the muscle, containing the mucosa and submucosal elements. Lip lifts can be designed to shorten the distance between the Cupid's bow and the base of the columella by lifting the lip and enhancing the vertical height of the dry vermillion.[23] Reshaping the lower lip also can be performed in this fashion.

Accurate preoperative planning is mandatory since even minor asymmetries are always clearly evident to the patient and observers. In addition, accurate psychological evaluation should focus on identifying patients with unrealistic expectations. Preoperative digital imaging or photo modifications can help in illustrating postoperative outcome and in operative planning.

Fat transfer

The procedure includes the following steps:

• Inform the patient of the need for a donor site and determine an appropriate site. In general, the periumbilical fat can be accessed quickly with a small incision within the umbilicus, which heals quickly and inconspicuously.

• Block the periumbilical fat tissue with an injection of local anesthetic solution of 1% lidocaine with epinephrine 1:100,000.

• After performing a small incision, harvest the fat tissue with 1.5-mm cannula and syringe suction. The volume obtained is variable but in general 20 mL of fat fraction results in 8-10 mL of injectable fat after decantation or centrifugation.

• Anesthetize the upper and lower lips, preferably by infraorbital and submental nerve block.

• Place the access incisions at the corner of the mouth, within the wet vermillion.

• Graft the fat in several layers through the vermillion and lip border, using the injection cannula in multiple passes of small volume to allow for better vascularization of the grafted fat. The injection ports may be left to naturally approximate or may be closed with a fine absorbable suture.

Tissue transfer - Superficial musculoaponeurotic system (SMAS)

At the time of the SMAS-ectomy face lift, retain strips of the SMAS removed. For the upper lip, tailor the strip approximately so that it is 4-6 mm in the center portion and tapered at the tip of each end. The length should be approximately 4-7 cm total. The lower lip graft should be 50-75% the size of the upper lip graft.

Block the lip with local anesthetic solution of 1% lidocaine with epinephrine 1:100,000 at least 10 minutes before augmentation and ideally a minimum of 20 minutes. Create a small incision at each lateral margin of the lip near the commissure. Pass a tendon passer from one end to the other.

Place the appropriate graft within the grasp of the tendon grabber and pull through the lip until the central portion is inline with the lip midline. Release the tendon grabber and trim any excess graft.

Massage the graft through the lip vermillion. Suture the access incisions with 5-0 fast absorbing plain gut suture.[24]

Implants

In general, implants are used as vermillion augmenters. The most commonly used biomaterial is AlloDerm, which in many cases has replaced synthetic fillers and PTFE. The implant procedure includes the following steps:

• Prepare AlloDerm according to manufacturer's specifications.

• Infiltrate the upper and lower lips with local anesthetic solution and make two small incisions in the corners of the mouth in the wet vermillion. A special passer is available for delivery of the graft or a standard tendon passer can be used to bluntly tunnel from one incision to the other in the submucosa-subcutaneous plane.

• Grasp the AlloDerm sheet and carry it through. Massaging the graft smoothes out the material and allows for better placement.

• Close the access incisions with fine absorbable sutures.

Surgical advancement

Preoperative evaluation of the lip anatomy is critical in assessing the position and size of the V-Y incisions. A 2:1 relationship exists between the length of the Y limb and the obtained increase in lip height. Therefore, the appropriate V-shaped incisions must be planned symmetrically on each side of the frenulum.

Infiltrate the lip tissue with a solution of 1% lidocaine and 1:100,000 epinephrine and anesthetize it by local nerve block.

Make the incisions and extend the dissection toward the lip margin in the submucosa plane, just superficial to the muscle, to avoid injury to the small sensory nerve branches in this area.

Once the planned advancement is obtained, carefully approximate the wounds with 4-0 absorbable sutures.

Lip lift

Preoperative markings are critical. Accurately mark the patient prior to injection and ask the patient to review and approve the markings. Even a 0.25-mm difference in vertical height between the peaks of the Cupid's bow can be noticed clearly postoperatively.

Anesthetize the upper lip and perform the planned full-thickness skin resection starting from the vermillion border. To decrease the chances of hypertrophic scarring, do not include the vermillion and skin directly within the philtral columns, corresponding to the prolabium, in the resection.

Close the wound with interrupted half-buried 5-0 Prolene sutures tied on the vermillion side of the wound.

See the list below:

• The areas treated with injectable materials require little postoperative care. Coat lips treated by surgical advancement or implantation with antibiotic ointment 3-4 times per day for 1 week postoperatively.

• Ice packs are used extensively in the first 24 hours.

• Encourage patients to limit talking, smiling, and laughing for 5-7 days postoperatively.

• Provide oral analgesics and instruct patients to rinse the mouth with saline solution 4-6 times per day for the first week postoperatively.

• Remove nonabsorbable sutures 5-7 days postoperatively.

See the list below:

• Significant postoperative swelling is common to all techniques of lip augmentation. The swelling usually resolves within 7-10 days, but it may persist for several weeks. Recommended postoperative care includes ice packs, sun avoidance, liquid diet, perioral care with saline rinses, and rest for 24-48 hours, depending on the extent of surgery. Inform patients of the significant swelling and bruising that may develop with this procedure; usually, they are able to tolerate it well.

• One of the most common complaints after surgical advancement is persistent numbness and/or paresthesias around the augmented lips. This problem usually resolves in 4-6 weeks but may become a significant nuisance for patients.

• Inform patients of the approximate duration of the significant swelling of the augmented lips; they should plan their social calendar accordingly.

• Follow-up care consists of office visits 1, 7, and 30 days postoperatively, at which time shape, symmetry, function, and wound healing are assessed.

Complications of collagen injection include allergic reaction to the compound, possible intravascular injection, skin slough, scarring, granuloma formation, and hematoma. Testing for sensitivity to bovine collagen must be performed prior to injection and observed for 4 weeks.

Complications of fat transfer include donor site hematoma, scarring, infection, lumpiness, asymmetry, infection, hematoma, intravascular injection, and possible skin slough.

Complications of synthetic material implantation include infection, asymmetry, sensitivity to the material, extrusion, need for removal of the implant because of hardening, interference with lip function, and sensation changes.

Complications of surgical advancement, lift, and roll include hypertrophic scarring, asymmetry, numbness, and lumpiness.

Outcome is generally good. Adequately informing patients of the expected postoperative course, possible complications, and required postoperative care is essential.

All available techniques of lip augmentation have advocates and critics. To date, a single most effective technique has not been identified, partly because of the wide variety of individual cosmetic complaints. Research in long-lasting injectables will likely lead to improved results.

The use of silicone oil injections has long been condemned in the United States because of the high rate of complications and tremendous difficulty in correcting the problems seen in patients who have undergone these procedures. Although this technique is not recommended in the United States, silicone oil injection has been reported as safe and successful outside the United States. The accuracy and long-term outcomes of these studies remain to be seen.[25, 26]

The future of soft tissue augmentation of the lip may be the use of combination therapies. Using the strengths of multiple injection materials could offer off-the-shelf convenience with safe and long-lasting results. For example, using hyaluronic acid (Restylane) in conjunction with calcium hydroxylapatite (Radiesse) minimizes complications seen with the latter when used alone and offers improved outcomes. In any event, any injectable material combination will be measured against the longevity and safety of dermal fat grafts.