In order to facilitate impression making, which factor is considered incorrect?

In the context of facilitative impression making in prosthetic dentistry, starting the preparation with guiding grooves is not considered an effective method. Guiding grooves may not provide the necessary clarity or precision needed to properly delineate the margins and contours required for an accurate impression. This could potentially lead to errors in the final restoration.

In contrast, creating proximal clearance of at least 0.6 mm ensures that there is sufficient space for the impression material and for the proper flow of the material around the prepared tooth, which enhances detail capture. A well-finished and smooth finish line configuration is critical because it helps the impression material to flow better and capture the precise details of the preparation, leading to a more accurate fit of the final prosthesis. Additionally, using a retraction cord is a standard practice that helps to manage soft tissue during the impression-taking process, preventing it from interfering with the impression and ensuring that the margins are clearly recorded. All these practices contribute significantly to achieving an optimal impression, while starting with guiding grooves does not align favorably with these objectives.