Final answer:
The kind of bur used to create the divergence of an inlay Class II preparation is typically a tapered diamond bur or a tapered fissure bur. These burs allow for outward tapering of the cavity walls, which is essential for the retention and proper fit of the inlay.
Step-by-step explanation:
In dentistry, particularly when preparing a tooth for an inlay, creating divergence is an important step. The divergence is necessary to ensure that the inlay can be properly placed without binding and to secure a tight fit once cemented. The kind of bur typically used to create divergence of an inlay Class II preparation is a tapered diamond bur or a tapered fissure bur. These burs are designed to provide the desired taper to the walls of the preparation. It is essential for the bur to have a tapered shape to allow for the divergent walls that are needed for the retention of the inlay.
During the tooth preparation process, the dentist uses these burs to create a cavity form that slightly tapers outward from the interior of the preparation to the outer surface. This ensures that when the inlay is seated, it will not be obstructed by any undercuts and can be easily placed and removed prior to cementation. Once the final inlay is cemented, the divergence aids in retention and prevents dislodgement during function.