In a Class II amalgam, where are retentive grooves typically located?

In the context of Class II amalgam restorations, retentive grooves are typically placed at the axiogingival point angles. These grooves serve a crucial role in enhancing the retention of the amalgam material within the cavity preparation. Specifically, the axiogingival area is where the axial wall of the cavity meets the gingival floor, and this positioning provides a mechanical interlocking of the restorative material, reducing the likelihood of displacement or failure over time.

Creating these grooves at the axiogingival point angles helps to not only retain the amalgam securely but also to ensure that the restoration has sufficient resistance against the forces that may be applied during chewing and other functional movements. This technique reflects best practices in conservative cavity preparation aimed at maximizing the longevity of the restorative materials used while minimizing compromise to the tooth structure.