Which instrument is used for shaping and smoothing cavities?

• A. Pear burs
• B. Fissure burs
• C. Light cure
• D. Shade guide

Answer: (A)

In shaping and smoothing a prepared cavity, the instrument should contour walls and floors with a rounded, forgiving tip. The pear-shaped bur fits this need best because its bulbous end allows efficient removal of imperfect surfaces while avoiding gouges or over-thinning at the margins. It lets you widen and refine the cavity gradually, creating smooth walls and a proper cavosurface finish that’s ready for the restoration. Fissure burs are more angular and are used for opening fissures or cutting grooves, not for smoothing wide cavity surfaces. Light cure and shade guide are not cutting instruments—one cures resin and the other helps match tooth color. So the pear-shaped bur is the most appropriate choice for shaping and smoothing cavities.