Abstract
The lip is positioned in the highly aesthetic center of the face and contributes numerous vital functions for speaking and eating. Optimal perioral reconstruction restores natural appearance and normal function and sensation. Masterful anatomic knowledge and meticulous execution help preserve oral competence and minimize asymmetries and scarring. Surgical planning is assisted by identifying the precise location, size, and depth of the defect. Successful reconstructive strategies performed for other facial units also apply to the perioral area. These include: preservation of skin contour, avoiding disruption of the vermilion-cutaneous junction, and aligning incisions along cosmetic junction borders and relaxed skin tension lines. Preoperatively counseling patients about expected healing timelines and potential staged revisions assist with achieving optimal patient outcomes.
Keywords
perioral, reconstruction, mouth, lip, commissure
Introduction
Skin cancer frequently occurs on and around the lips, and repairs of perioral surgical defects present numerous unique reconstructive challenges. Asymmetries and visible scars in the centrofacial region are distracting to onlookers, reduce levels of perceived attractiveness, and can create profound psychosocial stigma. In addition to its highly aesthetic positioning, the lip is a mobile subunit that contributes to speaking, facial expressions, mastication, and oral competence. Its sensory capabilities also allow for it to examine the qualities and temperature of food prior to eating. Successful reconstructive efforts recapitulate natural perioral anatomy, hide incisions discreetly, and fully restore function and sensation. As with other anatomic sites, thoughtful surgical planning and meticulous execution facilitate desirable outcomes. Small perioral defects are repaired in a single stage but can sometimes take many weeks for patients to return to their “baseline” appearance and functioning. Larger lip defects may be exquisitely difficult to repair in a single stage and patients should be counseled that certain repairs sometimes benefit from revision or staging to achieve optimal cosmesis and functioning.
Perioral Anatomy
The lips are prominently positioned in the lower central face, bounded by the nose above, cheeks laterally, and chin below. Adult lips are approximately 7 to 8 cm long with 4 to 5 cm between commissures in repose. The upper lip lies slightly anterior to the lower lip and is approximately half the height of the lower lip and chin. Similar to the nose and eyelids, the lips are a trilaminar structure with multiple delicately shaped subunits. From superficial to deep, skin covers a concentrically oriented muscle that is lined posteriorly by buccal mucosa. The bulk of the lip is formed by the orbicularis oris muscle, which consists of four independent quadrants that arise from the modiolus. Each quadrant contains a larger pars peripheralis and a smaller pars marginalis, with the two divisions meeting along the vermilion cutaneous junction (VCJ) to create the bulge of the white roll. Rather than a single collection of encircled muscular fibers, the lip should be considered a collection of eight unique muscular segments that work together for dynamic movement.
Surface Anatomy
The cutaneous skin of the lips is similar in thickness and composition to other centrofacial skin such as the forehead. In men, the terminal hair follicles produce a porous texture, while women have smoother cutaneous skin. Since the orbicularis muscle directly inserts into the undersurface of the perioral skin, dynamic muscular movement creates circumferential radial lines around the lips that are accentuated with pursing. These lines are ideal to hide incisions when reconstructing the lip. Sun damage and chronic smoking ultimately leave these lines etched into the skin and visible at rest.
The perioral region can be divided into five distinct subunits: two upper cutaneous subunits, philtrum, lower lip/chin, and vermilion lip ( Fig. 16.1 ). The upper lip has paired lateral cutaneous subunits that begin laterally at the melolabial fold and end medially at the philtral column. Each superolateral portion of these subunits has a small triangular portion of skin adjacent to the ala that is distinctly lip skin and not cheek or alar skin; these concave apical triangles favor heavily into reconstructive designs and must be preserved for optimal cosmetic outcomes. The philtrum is the medial concave subunit of the upper lip, and it is bounded by the convex philtral columns laterally, the columella superiorly, and the Cupid’s bow of the vermilion lip inferiorly.
The lower lip and chin are considered a single aesthetic subunit, and similar to the upper cutaneous subunits, the skin is approximately 8 to 9 mm thick and tethered to the underlying musculature. Of the two lips, the lower lip plays the greater role in oral competence by functioning as barrier to retain intraoral contents such as saliva.
Upper and lower lip skin transitions to specialized mucosa at the VCJ, where there is a marked change in native skin color to a pink–red hue due the thin, nonkeratinizing epithelium and abundant vascularity beneath. The vermilion mucosa is a distinct subunit devoid of salivary glands, and a coronal plane divides it into two components: an internal wet portion and an external dry portion, analogous to the gray line division of the eyelid. The transition from vermilion to cutaneous lip is seamless and forms an ideal location where incisions may be hidden.
Neuromuscular Anatomy
The muscles of facial expression attach radially along the outer margin of the orbicularis muscle in bilaterally paired sets to allow for dynamic facial animation and function. These lip elevators and depressors are innervated by the zygomatic, buccal, and marginal mandibular segments of the facial nerve. Many of these muscular fibers intersect at the modiolus, a tissue thickening that can be palpated 1.5 cm lateral to the commissure. The modiolus contributes to dimple formation and can be used as a point of fixation for certain flaps. Sensation to the upper lip is provided by the infraorbital nerve and sensation to the lower lip is provided by the mental nerve ( Fig. 16.2 ).
Vascular Anatomy
The blood supply to the perioral region is supplied by the facial artery, which is consistently identified in its corkscrew configuration crossing the border of the mandible at the anterior edge of the masseter muscle. As the artery crosses over the buccinator muscle, it runs underneath the depressor anguli oris and orbicularis oris muscles, where it gives off the inferior and superior labial arteries in succession. The labial arteries originate approximately 10 to 12 mm from the oral commissures to encircle the mouth by running within the salivary glands or buccal side of the orbicularis oris muscle. At the lateral portions of the lip, the labial arteries are approximately 10 mm apart from the lip margin then run closer to the surface as they progress medially. Additional arteries that perfuse the central lip include the columellar and septal perforators that arise from the superior labial artery and the mental artery that perfuses the chin and lower lip ( Fig. 16.3 ).
Introduction
Skin cancer frequently occurs on and around the lips, and repairs of perioral surgical defects present numerous unique reconstructive challenges. Asymmetries and visible scars in the centrofacial region are distracting to onlookers, reduce levels of perceived attractiveness, and can create profound psychosocial stigma. In addition to its highly aesthetic positioning, the lip is a mobile subunit that contributes to speaking, facial expressions, mastication, and oral competence. Its sensory capabilities also allow for it to examine the qualities and temperature of food prior to eating. Successful reconstructive efforts recapitulate natural perioral anatomy, hide incisions discreetly, and fully restore function and sensation. As with other anatomic sites, thoughtful surgical planning and meticulous execution facilitate desirable outcomes. Small perioral defects are repaired in a single stage but can sometimes take many weeks for patients to return to their “baseline” appearance and functioning. Larger lip defects may be exquisitely difficult to repair in a single stage and patients should be counseled that certain repairs sometimes benefit from revision or staging to achieve optimal cosmesis and functioning.
Perioral Anatomy
The lips are prominently positioned in the lower central face, bounded by the nose above, cheeks laterally, and chin below. Adult lips are approximately 7 to 8 cm long with 4 to 5 cm between commissures in repose. The upper lip lies slightly anterior to the lower lip and is approximately half the height of the lower lip and chin. Similar to the nose and eyelids, the lips are a trilaminar structure with multiple delicately shaped subunits. From superficial to deep, skin covers a concentrically oriented muscle that is lined posteriorly by buccal mucosa. The bulk of the lip is formed by the orbicularis oris muscle, which consists of four independent quadrants that arise from the modiolus. Each quadrant contains a larger pars peripheralis and a smaller pars marginalis, with the two divisions meeting along the vermilion cutaneous junction (VCJ) to create the bulge of the white roll. Rather than a single collection of encircled muscular fibers, the lip should be considered a collection of eight unique muscular segments that work together for dynamic movement.
Surface Anatomy
The cutaneous skin of the lips is similar in thickness and composition to other centrofacial skin such as the forehead. In men, the terminal hair follicles produce a porous texture, while women have smoother cutaneous skin. Since the orbicularis muscle directly inserts into the undersurface of the perioral skin, dynamic muscular movement creates circumferential radial lines around the lips that are accentuated with pursing. These lines are ideal to hide incisions when reconstructing the lip. Sun damage and chronic smoking ultimately leave these lines etched into the skin and visible at rest.
The perioral region can be divided into five distinct subunits: two upper cutaneous subunits, philtrum, lower lip/chin, and vermilion lip ( Fig. 16.1 ). The upper lip has paired lateral cutaneous subunits that begin laterally at the melolabial fold and end medially at the philtral column. Each superolateral portion of these subunits has a small triangular portion of skin adjacent to the ala that is distinctly lip skin and not cheek or alar skin; these concave apical triangles favor heavily into reconstructive designs and must be preserved for optimal cosmetic outcomes. The philtrum is the medial concave subunit of the upper lip, and it is bounded by the convex philtral columns laterally, the columella superiorly, and the Cupid’s bow of the vermilion lip inferiorly.
The lower lip and chin are considered a single aesthetic subunit, and similar to the upper cutaneous subunits, the skin is approximately 8 to 9 mm thick and tethered to the underlying musculature. Of the two lips, the lower lip plays the greater role in oral competence by functioning as barrier to retain intraoral contents such as saliva.
Upper and lower lip skin transitions to specialized mucosa at the VCJ, where there is a marked change in native skin color to a pink–red hue due the thin, nonkeratinizing epithelium and abundant vascularity beneath. The vermilion mucosa is a distinct subunit devoid of salivary glands, and a coronal plane divides it into two components: an internal wet portion and an external dry portion, analogous to the gray line division of the eyelid. The transition from vermilion to cutaneous lip is seamless and forms an ideal location where incisions may be hidden.
Neuromuscular Anatomy
The muscles of facial expression attach radially along the outer margin of the orbicularis muscle in bilaterally paired sets to allow for dynamic facial animation and function. These lip elevators and depressors are innervated by the zygomatic, buccal, and marginal mandibular segments of the facial nerve. Many of these muscular fibers intersect at the modiolus, a tissue thickening that can be palpated 1.5 cm lateral to the commissure. The modiolus contributes to dimple formation and can be used as a point of fixation for certain flaps. Sensation to the upper lip is provided by the infraorbital nerve and sensation to the lower lip is provided by the mental nerve ( Fig. 16.2 ).
Vascular Anatomy
The blood supply to the perioral region is supplied by the facial artery, which is consistently identified in its corkscrew configuration crossing the border of the mandible at the anterior edge of the masseter muscle. As the artery crosses over the buccinator muscle, it runs underneath the depressor anguli oris and orbicularis oris muscles, where it gives off the inferior and superior labial arteries in succession. The labial arteries originate approximately 10 to 12 mm from the oral commissures to encircle the mouth by running within the salivary glands or buccal side of the orbicularis oris muscle. At the lateral portions of the lip, the labial arteries are approximately 10 mm apart from the lip margin then run closer to the surface as they progress medially. Additional arteries that perfuse the central lip include the columellar and septal perforators that arise from the superior labial artery and the mental artery that perfuses the chin and lower lip ( Fig. 16.3 ).
Evaluation of the Patient and Defect
Perioral reconstruction, similar to other highly mobile and aesthetic facial units such as the eyelids, can be equal parts challenging, humbling, and rewarding. Algorithms for perioral reconstruction abound and may be a useful means early in one’s career to develop a conceptual framework. However, each patient’s face is unique and each patient’s aesthetic goals may vary. When embarking on lip reconstruction three fundamental pieces of information allow for development of an appropriate reconstructive plan:
- 1.
Where upon the lip is the defect located?
- ▪
Defects spanning more than one cosmetic subunit require more attention and effort than defects contained within a single subunit.
- ▪
Upper lip defects have different reservoirs of skin for reconstruction than lower lip defects.
- ▪
Philtral reconstruction is often more challenging than lower lip reconstruction.
- ▪
- 2.
What is the size and shape of the defect?
- ▪
The width of the lip that the defect spans is often the main determinant of repair type.
- ▪
The percentage of lip missing is a helpful guide for repair selection, but each patient’s skin laxity must be tested so as to avoid incisional tension or iatrogenic microstomia.
- ▪
Because of natural relaxed skin tension lines (RSTLs), defects that are greater in the vertical dimension are often less challenging to repair than defects that are greater in the horizontal dimension.
- ▪
- 3.
What is the defect depth?
- ▪
Dermatologic surgeons most frequently encounter partial-thickness lip defects that extend to the orbicularis muscle. When located on nonvermilion lip, these always benefit from suturing.
- ▪
Thin defects on mucosa granulate well.
- ▪
Full-thickness defects through muscle and mucosa require reapproximation of all three layers of tissue.
- ▪
General Principles of Perioral Reconstruction ( Box 16.1 )
- ▪
Three goals of perioral reconstruction:
- ▪
Maintain oral competence; preserve mobility and sensation; maximize cosmesis
- ▪
- ▪
Second intention works well for superficial vermilion defects.
- ▪
Incisions heal well when placed in relaxed skin tension lines (RSTLs) and within or parallel to aesthetic subunit boundaries.
- ▪
Oblique scars and skin grafts on the cutaneous lip are often conspicuous.
- ▪
The vermilion cutaneous junction (VCJ) is best marked with indelible ink or a scalpel before anesthetizing.
- ▪
Minimize swelling of local anesthesia by utilizing nerve blocks.
- ▪
Recruitment of skin for flaps is lateral to medial.
- ▪
Scar inversion is a greater risk in men because of a dense supply of folliculosebaceous structures.
- ▪
Muscular activity of the orbicularis oris increases likelihood of scar inversion and patients should be counseled to avoid opening their mouth widely in the postoperative period.
- ▪
Revisions may be necessary to achieve optimal results, especially for larger, composite defects.
Methods of Closure
Second Intention Healing
Second intention healing is a reliable approach for partial-thickness upper or lower mucosal lip defects, particularly in patients seeking to avoid additional reconstruction after tumor extirpation. Superficial defects restricted to the mucosal lip are often best managed with granulation alone ( Fig. 16.4A–B ). Patients are counseled to apply a thin coat of petrolatum after they cleanse their wound one to two times per day. With proper wound care small mucosal defects heal rapidly, and defects spanning the breadth of the entire mucosal lip will reepithelialize in less than 4 weeks because of rich anatomic vascularity ( Fig. 16.5A–B ). Larger lip defects with partial resection of orbicularis muscle and defects that cross the VCJ onto the cutaneous lip still may heal satisfactorily with second intention ( Fig. 16.6A–B ). Disadvantages of the second intention healing include visible stellate scarring, which may be more conspicuous when larger sized defects are allowed to granulate. Once fully healed, these smaller scars can be resected and repaired with minimal effort and recovery.
Mucosal Advancement Flap
Large mucosal defects, with or without muscle involvement, may be repaired with a mucosal advancement flap. This closure obviates the need for diligent daily wound care that must be performed for second intention healing. Flaps are designed off of the lateral aspect of the defect along the VCJ ( Fig. 16.7A ). Incisions are often carried from commissure to commissure, and redundant mucosal cones are removed in order to camouflage scarring (see Fig. 16.7B ). Undermining is performed posterior to the orbicularis oris by spreading the scissor tips to bluntly release the glistening yellow salivary glands off of the muscle (see Fig. 16.7C ). Elevating mucosa down to the gingival sulcus is often not necessary to facilitate stretching of mucosa to the VCJ, and minimizing the extent of undermining reduces postoperative hypoesthesia.
The flap is sutured in place with a single layer of sutures due to the thinness of the mucosa ( Fig. 16.7D–E ). When performed on the upper lip for philtral mucosal defects, a gull wing design for the mucosal advancement flap can restore the Cupid’s bow. Another variation of the mucosal advancement flap incorporates an axial myomucosal design by bluntly dissecting the labial artery and including it in the flap by incising through the orbicularis muscle, elevating the flap below the vessel, and sliding the flap laterally toward the defect.
While advancement of the mucosa provides immediate closure of certain lip defects, it possesses inherent disadvantages. The new lip is prone to cracking, and patients may find the need to moisturize with lip balm routinely. Patients frequently report loss of lip sensation, which can impair eating and drinking. Mucosal advancement flaps also decrease the anterior–posterior dimension of the lip, particularly for larger defects, and secondary flap motion can redirect beard hairs in men causing lip irritation.
Linear Closure
As with other facial subunits, linear closures (LCs) in the perioral region are a workhorse repair that can produce excellent results. When designed for appropriately sized lip defects within RSTLs or along cosmetic junction borders, scar visibility is reduced and free margin position is preserved. The ideal defect for an LC is partial thickness, situated in the middle of the lateral cutaneous subunit, and is taller than wider. LC of defects greater than one-fourth the width of the upper lip or one-third of the lower lip risks excessive incisional tension, displacement of the philtrum, or extending incisions perpendicularly beyond cosmetic junction borders.
Standard design of the LC creates straight tissue incisions off of the defect that form a rhombus shape with apical angles of 30 degree or less. The final length of most LCs is approximately 3 to 4 times longer than the short axis diameter of the defect. Burow triangles, approximately the same length or slightly larger than the defect diameter, may be designed off of the defect parallel to the lip’s radially oriented RSTLs. As defects are positioned more laterally on the subunit, the final design will be drawn more obliquely in order to mimic the RSTLs. Lateral-most defects can mirror the melolabial fold curvature if tissue approximation does not excessively displace the lip or commissure ( Fig. 16.8 ).
Contour of a scar should not be compromised in order to reduce scar length, because persistent tissue redundancies will negatively impact cosmesis. Redundant cones on the upper lip that extend past the VCJ or alar sill are precisely reapproximated to preserve the aesthetic junction lines. Tissue cones may be carried into the apical triangle/alar-facial sulcus with minimal aesthetic penalty if 1 to 2 mm of skin is preserved lateral to the ala ( Fig. 16.9 ). However, if the anticipated LC design extends perpendicularly past the NLF onto the cheek, then an alternative repair is better selected in order to avoid a noticeable step-off scar. Lower lip scar length can be reduced with implementation of an M-plasty ( Fig. 16.10 ).
Execution of LCs on the lip is identical to other locations on the central face. Redundant tissue cones (RTCs) are removed to the SMAS/muscle layer. In order to minimize incisional tension, the wound margins are sharply undermined with scissors to release skin from the tethering of the orbicularis oris. Undermining is performed up to 1 cm from the wound margin. Elevating tissue beyond this distance increases the possibility of postoperative bleeding and does not facilitate further tension reduction. Once meticulous hemostasis is achieved, suturing the lip is performed in a bilayered fashion, first with buried vertical mattress sutures and then with a cuticular layer of sutures.
There is little margin of error for suturing the cutaneous lip. Misalignment of the VCJ results in a jarring appearance and can detract from an otherwise seamless scar. In male patients the high density of follicular structures reduces the surface area of collagen gripped with each suture bite, thus increasing the risk of scar inversion ( Fig. 16.11 ). Attempts should be made to take greater bites of dermis in order to accentuate eversion and combat the natural forces that pull the scarline apart. Displacement of the VCJ can occur despite prudent LC design because of “central axis lengthening” that pushes the free margin away from the defect. Direct primary closures on the lip may also result in fullness of the lip due to an external rolling of the labial mucosa or compression of the underlying orbicularis oris muscle ( Fig. 16.12 ). While typically unfavorable, this pushing effect tends to be transient or can be revised with minor tissue resection. Asymmetry from inferomedial displacement of the melolabial fold may also occur if too large a redundant cone is removed from the lip’s apical triangle.
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
