Zinc phosphate cement restorations showed what compared to those not sealed?

• A. More pulpal irritation
• B. Less pulpal irritation
• C. Greater marginal leakage
• D. Higher wear

Answer: (B)

Sealing zinc phosphate cement restorations reduces the diffusion of the cement’s acidic components into the dentin and pulp. Zinc phosphate cement is very acidic when it sets, and if dentin is not protected, these irritants can reach the pulp and cause irritation. Placing a varnish or liner creates a barrier that lowers tubule permeability and limits the chemical attack on the pulp, so sealed restorations show less pulpal irritation than those left unsealed. While non-sealed restorations can have more pulpal irritation and sealing can influence leakage or wear in other contexts, the key effect here is the decrease in pulpal irritation with sealing.