Which type of instrument is designed specifically for removing subgingival calculus?

The correct choice is the curette, which is specifically designed for the removal of subgingival calculus. Curettes have a rounded tip and a spoon-shaped blade that allows them to be gently inserted beneath the gum line. This design is particularly effective for scraping and removing hard deposits from the root surfaces of the teeth without damaging the surrounding soft tissue.

In periodontal therapy, it is essential to access the area below the gum line to ensure effective cleaning and to promote healing. The curved blade of the curette enables the dental hygienist or nurse to work efficiently in tight spaces and reach areas that may be challenging with other tools.

In contrast, while push scalers are used for supra- and subgingival scaling, their sharp point is primarily effective for harder deposits on the surface rather than delicate areas under the gum. Periodontal files are more suited for smoothing root surfaces after scaling but do not facilitate the removal of calculus themselves. Ultrasonic scalers work by using vibrations to break down calculus, and while they can be effective for subgingival cleaning, they are not as precise as curettes when it comes to meticulous removal in deep or sensitive areas. This makes the curette the best-suited instrument for accessing and removing subgingival calculus.