What is the main characteristic of a round bur?

The main characteristic of a round bur is that it is designed specifically for the removal of caries. This type of bur features a spherical shape that allows it to efficiently excavate decayed tooth structure. The rounded design facilitates access to the cavity while minimizing damage to surrounding healthy enamel and dentin.

Round burs are commonly used at the initiation of cavity preparation because their shape allows for effective breakdown and extraction of carious tissue. This characteristic is especially important when preparing teeth for restorative procedures, ensuring that all decay is completely removed to promote optimal healing and restoration success.

Other options describe different types of burs or uses. For instance, tapered shapes indicate a different bur design that may be used for different purposes, such as creating an undercut in preparation for a filling. A pointed tip typically belongs to a different bur type used for shaping and finishing rather than caries removal. While cavity preparation is a broader category, not all burs are designed for this specific function, making the round bur's primary feature as a tool for caries removal distinctly important.