The Vermillion Border of the Lip: Does Its Exclusive Terminology Make You See Red?

Purpose: The region of the facial lips commonly referred to as the “vermillion border” (VB) literally means “red outline”. Its exact classification, however, appears to vary between anatomical textbooks and in the scientific literature. This study sought to identify the anatomical (surface anatomical and histological) definition of the term VB and asks the question: in a modern multicultural society, where not every human has red lips, does the term VB require a shift to a more inclusive terminology?

Methods: Searches were performed on historical and modern anatomical literature to find the descriptions and definitions of the term VB.

Results: The term VB first appears in surgical and pathological descriptive literature around the 1850s, while its adaptation into anatomical texts appears to be more recent.

There is considerable variability in the literature regarding its classification, at both the surface anatomical and histological levels. For surface anatomy its classification ranges from the thin muco-cutaneous line of junction between the skin and coloured part of the lip up to the entire coloured region of the lip joining the skin to the internal oral mucosa. Histologically, its classification ranges from non-keratinised to keratinised stratified squamous epithelium (i.e. mucosa to thin skin).

Conclusion: The VB is a controversial anatomical feature of the human body. Not only due to the variability of its classification, but also to its exclusive, Caucasoidcentric terminology. The VM is described in Terminologica Histologica as Pars Intermedia of the Labia oris; therefore, I propose that the term VB be replaced with the term Intermediate Lip.