Hyung Jin Ahn1, Won-Soo Lee. 1. Department of Dermatology, Yonsei University Wonju College of Medicine, Kangwon-Do 220-701, Republic of Korea.
Abstract
INTRODUCTION: Hair fibers are comprised of non-nucleated keratinocytes and are biologically dead. Clinical damage to the hair shaft occurs with the application of hair dye. Whether this damage can be repaired and the time frame involved is of interest and may help to determine the optimal interval between repeat applications. AIMS AND METHODS: Ultrastructural changes of hair shafts after application of permanent hair dye were observed sequentially in a 26-year-old woman. The dye contained p-phenylenediamine, m-aminophenol, resorcin and hydrogen peroxide as an oxidizer. Scanning and transmission electron microscopy was performed immediately before application of the hair dye and again at 30 min, 1 h, 3 h, 6 h, 1 day, 3 days, 1 week, 2 weeks, 4 weeks, 6 weeks and 8 weeks. RESULTS: The hair showed cuticular swelling with focal degeneration. In some places there was exposure of the hair cortex due to extensive cuticular detachment. There were many holes of various size in the endocuticle, small focal lacunae along the intercellular space and an ill-defined A-layer especially beneath the area of cuticular detachment. The exocuticle appeared normal. The findings were most dramatic in the 6 h and 1 day specimens and tended to improve gradually thereafter. The 8 week specimen showed near complete restoration of the hair cuticle and return to the precoloring state. CONCLUSION: Hair returns to its precoloring state and this requires 8 weeks.
INTRODUCTION: Hair fibers are comprised of non-nucleated keratinocytes and are biologically dead. Clinical damage to the hair shaft occurs with the application of hair dye. Whether this damage can be repaired and the time frame involved is of interest and may help to determine the optimal interval between repeat applications. AIMS AND METHODS: Ultrastructural changes of hair shafts after application of permanent hair dye were observed sequentially in a 26-year-old woman. The dye contained p-phenylenediamine, m-aminophenol, resorcin and hydrogen peroxide as an oxidizer. Scanning and transmission electron microscopy was performed immediately before application of the hair dye and again at 30 min, 1 h, 3 h, 6 h, 1 day, 3 days, 1 week, 2 weeks, 4 weeks, 6 weeks and 8 weeks. RESULTS: The hair showed cuticular swelling with focal degeneration. In some places there was exposure of the hair cortex due to extensive cuticular detachment. There were many holes of various size in the endocuticle, small focal lacunae along the intercellular space and an ill-defined A-layer especially beneath the area of cuticular detachment. The exocuticle appeared normal. The findings were most dramatic in the 6 h and 1 day specimens and tended to improve gradually thereafter. The 8 week specimen showed near complete restoration of the hair cuticle and return to the precoloring state. CONCLUSION: Hair returns to its precoloring state and this requires 8 weeks.
Authors: Feroze Kaliyadan; B B Gosai; Walid Naief Al Melhim; Kaberi Feroze; Habib Ahmad Qureshi; Sayed Ibrahim; Joel Kuruvilla Journal: Int J Trichology Date: 2016 Apr-Jun
Authors: Gregoire Naudin; Philippe Bastien; Sakina Mezzache; Erwann Trehu; Nasrine Bourokba; Brice Marc René Appenzeller; Jeremie Soeur; Thomas Bornschlögl Journal: Proc Natl Acad Sci U S A Date: 2019-08-26 Impact factor: 11.205