What is a potential result when peroxides reach pulpal tissue through enamel?

• A. Cytotoxic effects on pulpal tissue
• B. Increased enamel thickness
• C. Pulpal mineralization
• D. No effect on pulpal tissue

Answer: (A)

Peroxides that reach the pulp through enamel introduce oxidizing agents that generate reactive oxygen species. These species can diffuse into pulpal tissue and attack cellular components—membranes, proteins, and DNA—causing oxidative stress, inflammation, and potential cell death. That cytotoxic effect is the main risk when peroxide penetrates toward the pulp, which is why whitening agents can produce transient sensitivity or, with higher exposure, more significant pulpal irritation. The extent of this effect depends on factors like peroxide concentration, exposure duration, and the thickness of enamel and dentin protecting the pulp.

Enamel thickening is not a consequence of peroxide reaching the pulp, and pulpal mineralization is not a typical immediate outcome of peroxide diffusion. While some mild, reversible pulpal irritation may occur with whitening, a complete lack of effect is unlikely if peroxide actually reaches the pulp.