AUTHORS: 1Thomas M. Beachkofsky, MD, 2 J. Scott Henning, DO, 2Chad M. Hivnor, MD

RESEARCH SITES: 1U.S. Air Force, Kunsan Air Base, Republic of Korea. 2Department of Dermatology, Wilford Hall Medical Center, Lackland Air Force Base, Texas

PUBLICATION: Dermatol Surg. 2011 Sep, 37(9):1365-8

YEAR: 2011

For many years, the human hair follicle was thought to form only during primary development and to be unable to be regenerated if destroyed or lost. Although its complex development has been intensely studied, the morphologic stages and numerous biochemical cascades characteristic of human hair follicle growth and development are poorly understood. Consequently, it is a source of intense research.

More than 50 years ago, Kligman and Strauss described the regeneration of vellus hair follicles and sebaceous glands on the face after dermabrasion. Gillman and Penn showed similar findings during healing of incised wounds. Although the validity of these findings has been questioned, numerous researchers have shown post-traumatic de novo hair follicle regeneration in many nonhuman mammalian species, including mice, rats, rabbits, and guinea pigs, although there continues to be a paucity of human studies, and published case reports are rare and offer incomplete detail.

Here we present original case reports of three patients with scarring of distinct etiologies. All experienced new hair growth within fractionated carbon dioxide (CO2) laser treatment areas. We believe these incidental findings may represent de novo hair follicle regeneration inside the borders of post-traumatic hypertrophic scarring or grafting.