19.3 Lesson 3: Other Acquired Hair Fiber Problems

Structural defects of the hair shaft can cause significant cosmetic problems, or they may render the hair abnormally susceptible to injury by minor degrees of trauma:
- - Using a dryer that is too hot can boil the water in the hair shaft and cause “Bubble Hair” where the hair strand is weakened as bubbles form in the hair shaft.
  - Trichorrhexis Nodosa is where cuticle cells become damaged due to chemical or physical trauma, which causes the cortical cells to splay out and form nodes. These nodes are usually very weak and allow for the hair to break easily at these points.
  - Trichoptilosis describes the longitudinal splitting of the hair shaft. It is also called split ends. This condition is also caused by chemical or physical trauma.
  - Trichonodosis is the knotting of the hair. It can occur spontaneously or through styling mistakes. Breakage frequently occurs, especially as the knot is removed.
  - Trichoclasis is hair breakage that is seen as a clean fracture across the hair fiber.
  - Plica Polonica is where the hair irreversibly tangles and is matted together; usually due to poor grooming (unwashed hair for considerable length of time).