What is the term for the junction of two internal walls in a cavity preparation?

The term that describes the junction of two internal walls in a cavity preparation is indeed identified as a line angle. In dentistry, when creating a cavity preparation for a restoration, various angles and junctions are formed where two wall surfaces meet. These junctions can be characterized in different ways.

A line angle specifically refers to the intersection of two plane surfaces within the cavity. It is significant because it helps dental professionals understand the structural integrity of the preparation and ensure that there is enough space for the filling material while maintaining the right contours for optimal healing and function.

Understanding line angles is crucial for effective cavity design and ensures that restorations fit properly and have the necessary strength and durability after placement. This term is distinct from other concepts. For instance, a point angle refers to the junction of three walls, and the cavo-surface margin is the area where the cavity preparation meets the enamel surface, which serves a different purpose in cavity assessment and preparation. The proximal surface refers to the sides of adjacent teeth and is not relevant when discussing internal wall junctions specifically.