Reconstruccion De Labio

LIP RECONSTRUCTION
H.D. Vuyk and Ch.R. Leemans

INTRODUCTION Cancer of the lip is a relatively common malignancy of the head and neck region. Squamous cell carcinoma most frequently occurs in the mucosa of the lower lip, while basal cell carcinoma is the most common cancer of the cutaneous portion of the upper lip. Obviously cure should always be prioritised over reconstruction. As tissueconservation is critical in this location, tumour extirpation is ideally accomplished through meticulous margin control as permitted by Mohs micrographic surgery. For reconstruction of the lip unit, a large spectrum of modalities have been described. To obtain consistent optimal results, a combination of reconstructive skills and aesthetic sensitivity is required.

ANATOMY The lips comprise twomobile structures that represent the anterior boundaries of the oral cavity. The lips function dynamically in deglutition, speech and facial expression9. The skin of the lip is intimately attached to the orbicularis muscle. The orbicularis oris muscle forms the bulk of the lip and is arranged in a circular fashion. Maintenance of continuity of the orbicularis is highly important for oral competence.In opening and closing of the mouth the orbicularis works synergistically with a group of dilator muscles arranged in a radial fashion around the mouth. Blood supply comes from superior and inferior labial arteries, which are branches of the facial artery. These arteries run submucosally just on the internal side of the lip vermilion forming a vascular arcade. The buccal and marginal mandibularbranches of the facial nerve supply the motor innervation. The first echelon lymphatic drainage is to the submental and submandibular lymph nodes (level I). Boundaries of the anatomic lip unit include melo-labial creases, base of the nose and mental crease (Fig. l). The upper lip itself may be divided into 3 smaller topographic units. The philtral column, nostril sill, alar base and nasal-labialcrease border both lateral subunits. The medial topographic subunit includes the philtrum itself 4. A thin pale junction zone of skin (white line) separates the cutaneous part of the lip from the vermilion portion. This junction zone should be aligned correctly for adequate aesthetic lip repair. The lower lip presents as a separate anatomic unit. The borders of the aesthetic units afford an excellentlocation for camouflage of scar lines in lip repair. When a large part of the subunit of the lip is missing, consideration should be given to replace the entire subunit rather than simply patching the defect. In essence, a relatively larger operation aims to place the scar at the subunit transition zones4. As the creases often distinctly outline the anatomic unit, distortion of these lines inreconstruction should be prevented. In general, incisions should preferably be
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Lip reconstruction

Fig. 1. Lip anatomy with defined structural boundaries and surrounding aesthetic units. Delineating 2 lateral and 1 central upper lip sub-units, whereas the entire lower lip represents a separate aesthetic unit.

limited within the lip unit and not extend across these anatomic borderlines.Relaxed skin tension lines of the lip are oriented in a radial fashion around the mouth. They have a perpendicular orientation with respect to the underlying circular orbicularis oris muscle28. Age related wrinkle lines do follow these relaxed skin tension lines and thus are indication for preferred incision placement.

RECONSTRUCTIVE STRATEGIES OF THE UPPER AND LOWER LIP Functional goals of lipreconstruction include maintenance of oral competence, sufficient oral access and preservation of sensation. Aesthetically, facial units should be reconstructed with adequate tissue match in terms of colour and texture, aiming at symmetry as well as preservation of the apparent commissure and philtral structures9. The four main reconstructive options include secondary intention healing, skin...