PSI Barbering Practice Exam 2025 - Free Barbering Practice Questions and Study Guide

Iontophoresis is specifically associated with the introduction of water-soluble products into the skin due to its use of electrical currents. This technique involves applying a mild electrical current to the skin, which facilitates the penetration of these products by using positive and negative charges to push the ions of the solution through the skin barrier.

Microdermabrasion primarily focuses on the physical exfoliation of the skin's outer layer and does not involve the introduction of products into the skin. Massage, while beneficial for increasing circulation and lymphatic flow, does not specifically aid in the penetration of water-soluble products at a molecular level. Exfoliation helps remove dead skin cells, enhancing the overall appearance and texture of the skin but does not directly facilitate deeper product absorption like iontophoresis does. Therefore, iontophoresis stands out as the process dedicated to effectively introducing water-soluble ingredients into the epidermal layers.