The cavosurface angle for inlay cavity preparation
**Core Concept**
The cavosurface angle is a critical aspect of dental cavity preparation, influencing the strength and durability of the restoration. In dental anatomy, the **cavosurface angle** refers to the angle formed by the prepared cavity wall and the surface of the tooth.
**Why the Correct Answer is Right**
For an inlay cavity preparation, a **90-degree cavosurface angle** is typically recommended to maximize the strength of the tooth-restoration interface and minimize stress concentrations that could lead to fracture. This angle allows for an optimal seal and supports the restoration, enhancing its longevity.
**Why Each Wrong Option is Incorrect**
**Option A:** An angle less than 90 degrees may lead to inadequate support of the restoration, potentially causing it to fracture under occlusal forces.
**Option B:** An angle greater than 90 degrees could result in a weaker tooth structure, as more tooth material is removed.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the ideal **cavosurface angle** for inlay preparations is 90 degrees, which provides the best compromise between preserving tooth structure and ensuring the restoration's durability.
**Correct Answer:** C. 90 degrees