What type of perm uses heat to process the hair?

A hot perm utilizes heat to process the hair, which differentiates it from other perm types that operate without added warmth. The heat facilitates the chemical reactions necessary to break down the hair's disulfide bonds, allowing it to be reshaped. This process encourages the cuticle to remain more open and allows for a more thorough penetration of the perm solution, resulting in looser, more defined curls that can withstand humidity and maintain their shape longer.

While other perms may utilize different methods, such as the cold perm, which relies solely on the chemical solutions without heat, or the alkaline perm, which also operates at room temperature, the hot perm stands out for its use of heat. Digital perms, specifically, use a heat-controlled process but involve a more modern machine that regulates temperature digitally for optimal results. Understanding these differences is essential for cosmetologists to choose the right perm method based on desired outcomes and hair types.