3D RECONSTRUCTION OF HUMAN HAIR BY CONFOCAL MICROSCOPY

Confocal microscopy is a highly original, non-destructive method for o bserving objects in three dimensions and in their natural environment. As such, it is well suited to studies of human hair. The tandem-scann ing reflected-light microscope was used to study the hair surface in i ts natural environment, which included sweat and sebum. Micrometric me asurements assessed the effects of classical treatments (permanent wav ing and bleaching), swelling in water and urea solution, and stretchin g. A confocal laser scanning microscope was used to reconstruct a volu me of hair shaft. The internal structures (cortex and medulla) were co ntrasted using a fluorescent marker (rhodamin) and could be observed i n both longitudinal and transverse optical sections at all levels. Our results demonstrate the value of confocal microscopy in describing ha ir structure and the effects of treatments on the cuticle. Methods bas ed on classical optical and electron microscopy are far more complex a nd time-consuming than confocal microscopy, which represents an extrem ely promising technique for cosmetic research.