Anatomically short lips that cannot close properly at rest are termed incompetent lips. This condition leads to inadequate lip seal, resulting in problems such as dryness, increased risk of dental caries, and altered facial esthetics. In contrast, competent lips can comfortably close without strain. Recognizing lip incompetence is crucial in pre-surgical assessment for procedures involving the perioral region, such as cleft lip repair, to ensure restoration of proper function and facial balance. Surgical correction often involves techniques to lengthen or reposition lip tissues to achieve competent closure.

Reference: Gray's Anatomy, 42nd Edition.