Epithelialized

Epithelialized is an adjective used in biology and medicine to describe tissue surfaces that are covered by epithelium. Epithelium is a cellular tissue that lines body surfaces and cavities and forms glands; it provides barriers against injury and infection, regulates permeability, and supports secretion and sensation. A surface described as epithelialized has a continuous layer of epithelial cells overlaying the underlying tissue, often reflecting the tissue’s normal lining such as stratified squamous or simple columnar epithelium.

In wound healing, epithelialization refers to the regrowth and migration of epithelial cells across a wound bed from the edges toward the center, restoring the epithelial barrier. The rate and quality of epithelialization depend on factors including wound size and depth, moisture, infection, and systemic health. When a wound is too large or compromised, medical or surgical interventions—such as skin grafts, dermal substitutes, or barrier dressings—may be employed to support epithelialization.

In clinical practice, the term may describe surfaces that have re-epithelialized after injury, surgery, or the placement of implants or grafts. An epithelialized surface is generally more resistant to infection and fluid loss and better suited for protection and function in the respective anatomical site, whether skin, mucosa, cornea, or other linings.

Terminology note: epithelialization is the process by which epithelium forms a new surface, and epithelialized tissue denotes completion of that epithelial layer. The specific epithelium type and location vary by organ system.