What can cause over contoured restoration?

Over contoured restorations occur when there is an excessive amount of material used in the restoration, leading to an unnatural contour that can affect both aesthetics and functionality. Insufficient axial reduction is a primary cause because it refers to not removing enough tooth structure from certain axial walls during the preparation phase. When the preparation lacks adequate reduction, any material added to restore the tooth can result in contour that is too bulky or excessive. This can lead to issues like improper occlusion, difficulties in flossing, and potential periodontal concerns due to inadequate interproximal space.

In contrast, other factors such as undercuts of preparation, overextension of margins, or incorrect material selection may influence the fit or longevity of the restoration but do not directly lead to over contouring in the same way. Under cuts might create retention problems, overextension could lead to issues with the margin, and material selection impacts durability and aesthetics, but they do not necessarily correlate with excessive restoration volume in the way that insufficient axial reduction does. Understanding the interplay between preparation techniques and restoration contouring is crucial for achieving optimal prosthetic outcomes.