What is the side bond that is of the greatest concern to a salon professional?

The side bond of greatest concern to salon professionals is the disulfide bond, which is crucial for the structural integrity of hair. These bonds can be broken and reformed through chemical processes like perming or relaxing, affecting hair strength and elasticity. When damaged, they can lead to hair breakage and overall health deterioration, making it essential for professionals to understand how to protect and restore these bonds during treatments.