Upper Lip Anatomy, Mechanics of Local Flaps, and Considerations for Reconstruction.

Reconstruction of defects involving the upper lip can be challenging. The purpose of this review was to analyze the anatomy and function of the upper lip and provide an approach for reconstruction of upper lip defects. The primary role of the upper lip is coverage of dentition and animation, whereas the lower lip is critical for oral competence, speech, and eating. The orbicularis oris (OO) and several other muscles contribute to upper lip function. There are various insertion points for animation muscles, including the upper lip dermis, OO, and modiolus. Special attention should be paid to the philtrum, Cupid's bow, and vermilion border during reconstruction. Advantages and disadvantages of the Abbe, Estlander, and Karapandzic flaps are presented. Knowledge of mechanics, indications, and properties of local flaps while considering unique characteristics of upper lip anatomy and function are crucial for optimal aesthetic and functional outcomes.