Scarring of the proximal nail fold region involving the matrix (nail growth center) is referred to as pterygium (not to be confused with the common cuticle overgrowth that is often incorrectly referred to as pterygium). This disorder is actually an overgrowth of the proximal nail fold onto the nail bed. By definition, pterygium forms if there is scar tissue in the nail matrix. Since the nail matrix at that particular site cannot manufacture nail plate, the proximal nail fold skin grows out with the skin of the nail bed, giving rise to the triangular formation known as pterygium. A number of skin and nail disorders may cause pterygium to form. There are two approaches to treat pterygium. The first is used if the pterygium is permanent due to scarring, but the primary disease is now inactive. Under some circumstances, these clients may be helped by surgical reconstruction with the removal of the pterygium and the scar tissue in the matrix, which results in a nail more cosmetically acceptable than it was before. In patients whose pterygium formation is still in an active stage, then the treatment would be directed at the primary disorder. Once the disorder is brought under control, further scarring will not occur and pterygium can be reduced or even prevented.