Hair breakage is a multifactorial phenomenon involving bending,
stretching and torsion deformations and includes:
• Tangle formation with hair fibers looped over other hairs with
severe bending deformations as shown by Brown and Swift31
• Knots that form more in hair with high curvature and are
easily fractured32
• Treatments and weathering: Chemical damage increases
breakage and conditioners decrease breakage33-38
• Relative humidity (RH) or water content of the hair: Highly
coiled hair breaks more by dry state grooming, while straight
to wavy hair provides more short segment breaks (< 2.5 cm)
when dry, but more long segment breaks when wet38, 39
• Impact breakage or pulling a comb or brush through a tangle
with breakage40
• Physical damage or wear by abrasion from specific grooming
devices such as combs, picks or brushes and to some extent a
fatiguing action