Which instrument is used to remove any unsupported enamel from cavity edges?

• A. Enamel chisel
• B. Mouth mirror
• C. Flat plastic
• D. Amalgam plugger

Answer: (A)

Removing unsupported enamel at the cavity edge requires a cutting instrument with a sharp, beveled edge designed to pare away enamel without damaging the surrounding dentin. The enamel chisel fits this purpose perfectly. Its blade is shaped to bite into the thin, unsupported enamel and cleanly remove it, creating a true, supported margin that’s less prone to fracture or marginal leakage when the restoration is placed. It’s used with controlled tapping or light blows to avoid gouging dentin and to keep margins neat and true.

The other tools don’t serve this purpose. A mouth mirror is for indirect vision and retraction, not cutting enamel. A flat plastic instrument is typically used for shaping or carving soft materials, not for removing hard enamel. An amalgam plugger condenses material and helps carve the restoration after placement, but it cannot cut away unsupported enamel.