Which instrument is commonly used to explore for calculus on root surfaces?

• A. Scaler
• B. Explorer (periodontal probe/explorer)
• C. Curet
• D. Chisel

Answer: (B)

Exploring for calculus on root surfaces relies on tactile feedback. An explorer has a fine, pointed tip and a flexible shank that lets you glide along the root and feel differences in texture. This sensitivity helps you detect calculus deposits, grooves, or rough areas that are often subgingival and not visible, allowing precise localization and assessment of irregularities beneath the gingival margin. Because its purpose is to sense and map surface texture rather than remove deposits, it’s the tool of choice for exploring root surfaces.

Scalers and curets are designed to remove calculus and smooth root surfaces, not to probe for delicate textures. Their broader blades and working ends aren’t suited for feeling fine detail, and using them as explorers could damage tissues. A chisel is used mainly for shaping or removing hard tissue in different contexts, not for periodontal exploration.