Dilated human hair fiber after exposure to flames for 'split ends' cutting.

Abstract

Studies show that split ends are often caused by grooming abrasion, especially in hair sensitized by chemical treatments. Standard treatment involves cutting the affected area with sharp scissors. New techniques, like nanostructured lipid carriers, are being tested to address split ends. In Brazil, the candle flame technique "velaterapia," based on the ancient practice of Brûlage, is gaining popularity. However, exposure to flames can cause hair damage, as hair fibers begin to denature at 237ºC, leading to issues like bubble formation. SEM-FEG images of virgin Caucasian hair samples show that these bubbles damage the cuticle by inflating the cortex, exposing and unprotecting it. The thermal protector used in velaterapia, while not fully insulating, does protect cuticles from melting. Due to the technique's rising popularity, further studies using tensile strength testing and spectroscopic analyses are needed to evaluate other potential damage to hair fibers.