Which instrument is most suitable for removing subgingival calculus from root surfaces?

• A. Mouth mirror
• B. Sickle scaler
• C. Periodontal curette
• D. Spoon excavator

Answer: (C)

Removing subgingival calculus relies on an instrument that can safely reach beneath the gumline and conform to the contours of the root surface. A periodontal curette has a rounded toe and two cutting edges specifically shaped to scale and plane root surfaces below the gingival margin, minimizing tissue trauma while effectively removing calculus and biofilm from root surfaces.

The other instruments aren’t suited for subgingival work: a mouth mirror is only for vision and illumination, not calculus removal; a sickle scaler is sharp and pointed mainly for supragingival deposits and can injure soft tissue if used below the gumline; a spoon excavator is designed for caries removal and scraping dentin, not for root surfaces or calculus.