Which bur is used for shaping and outlining cavities?

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

Answer: (B)

Shaping and outlining cavities needs a bur that can create precise margins and clean line angles with controlled tooth reduction. Fissure burs have a narrow, straight or slightly curved cutting edge arranged along a fissure, which lets you cut along the cavity walls and outline with accuracy. This design makes them ideal for defining the internal geometry and establishing the outline before deeper shaping or restoration. Pear burs, while useful for broader reduction and contouring, are larger and less suited for precise outlines. Light cure and shade guide aren’t cutting tools at all—they’re a curing light and a shade-matching device, respectively.