What is the main use of a straight fissure bur-plain cut?

The straight fissure bur-plain cut is primarily utilized in cavity preparation for cutting and shaping tooth structure. Its design allows for effective and precise angling of cavity walls, which is essential in the process of cavity preparation. In addition to this, it is also employed to create the main cuts in the cavity, allowing for efficient removal of decayed tissue.

The ability of the straight fissure bur to create angles and facilitate cavity formation is vital in ensuring that the restoration has optimal retention and is shaped correctly to restore tooth function. This bur's multifaceted use in both creating angles and cutting cavity walls exemplifies its importance in restorative dentistry, enhancing its value in various procedures.

In contrast, other options may focus on narrower aspects of its functionality, but the correct answer comprehensively covers its dual purpose, making it indispensable in cavity preparation.