Damage and Regeneration of Hair Cuticles After Permanent Coloring: Sequential Microscopic Changes / 대한피부과학회지

ABSTRACT

BACKGROUND: The effects of external chemicals on the hair shaft are of great interest in both the medical field and the cosmetic industry. Current methods to analyze these effects consist mainly of macroscopic testing such as touch and tell little about the actual hair morphology. OBJECT The purpose of the present study was to evaluate the morphologic changes of hair shaft, especially cuticle, after aoplication of permanent dye. METHODS: The coloring was performed as routine procedures. The time of contact of the dyeing solution within the scalp and hair was 30minutes. The coloring process ends with a through rinsing with water, Scanning electron microscopic findings of hair cuticle was observed sequentially before and after application of hair dye. RESULTS: After 30minutes, cuticular swelling without degeneration was seen As the swelling improve, the cuticular degradation was noted initially at 90minutes, By the 2 hours to the 1 week gradual progression of cuticular degradation was noted. By 1week after coioring, cortical exposure due to extensive cuticular detachment was observed. The reaction reached a peak between 1 and 2 weeks. Then, damaged outicles were gradually regenerated and returned to pre-treatment states by 8weeks. CONCLUSION: The hair fibers take l month to grow out by 1cm, at which point a fresh dye application becomes necessary. However, aithough the cuticles were regenerating, the cuticular damage still remained after 6 weeks. So, we concluded that interval of coloring is required more than 8 weeks. But further study to protect cuticle and to improve regeneration will be needed for shortening of regeneration time.