Lip Lesion or Deformity

Bruce K. Tan

Lips form the anatomical boundary at which mucosalized epithelium transitions to become keratinized squamous epithelium. As a result, diseases affecting both mucosa as well as skin can manifest on the lips. Because lips play a prominent role in facial aesthetics, enunciation, and maintaining oral competence, lip lesions or defects are readily noticeable and can be devastating for social interaction. Lip abnormalities include congenital errors of embryological development, acquired lesions resulting from trauma and aging, manifestations of systemic disease or infection, and both benign and malignant neoplasms. This section focuses on those conditions that may involve treatment by the facial plastic surgeon.

Congenital Lip Abnormalities

Congenital lip abnormalities are among the most common craniofacial developmental abnormalities. Of these cleft lip is the most common, and is asso ciated with a cleft palate in 68 to 86% of patients.

Cleft lip: Can be either unilateral or bilateral and occurs only on the upper lip (Fig. 75.1). Cleft abnormalities result from the nasal and maxillary prominences failing to fuse in midline during the fifth and sixth week of intrauterine development. The severity of clefting can also vary:

Microform cleft lip is a dehiscence of the orbicularis muscle with associated vermilion notching but intact overlying skin.

Incomplete cleft lip spares some of the superior upper lip.

Complete cleft lip involves all three layers with none of the upper lip crossing midline.

Labial frenulum: May involve the upper or lower lips. In infants, the labial frenulum typically extends over the alveolar ridge and should regress after the eruption of teeth. An aberrant frenulum can lead to periodontal disease and bone loss.

Congenital double lip: May present in isolation or as a component of Ascher syndrome. Patients with a double lip have a fold of excess or redundant tissue that appears on the mucosal side of the lip when the lip is tensed during smiling.

Congenital lip pit: A depressed sinus lined with stratified squamous epithelium that communicates with the minor salivary glands. Saliva can be expressed from these pits when pressure is applied. This may occur at the oral commissure, the midline upper lip, or the lower lip. Children with the autosomal dominant Van der Woude syndrome have bilateral lip pits on the vermilion of the lower lip and cleft lip or palate.

Fig. 75.1 Infant with a unilateral cleft lip on the right side and a cleft-associated nasal deformity characterized by an inferior and lateral displacement of the nasal alar.

Microstomia: Commonly associated with holoprosencephaly as well as other congenital syndromes such as the Freeman-Sheldon syndrome.

Macrostomia: Extremely rare but can result from abnormalities of branchial arch development.

Lip Trauma

Lip trauma can result from a variety of mechanisms ranging from blunt force trauma to avulsion or electrical injury. In repairing traumatic injury to the lip, attention must be paid to restoring both cosmesis and functionality.

Lip contusion: Results from blunt force injury of the perioral soft tissue. Substantial soft tissue swelling can occur in this area.