Description

Impression compound is a rigid, reversible dental impression material that sets through a physical change, primarily used for making impressions of edentulous ridges. It is classified into two types: Type I for general impressions and Type II, known as tray compound, which is used to prepare trays for more detailed impressions. The material is supplied in various forms including sheets, sticks, cakes, and cones, and has seen decreased use due to the rise of acrylic tray materials.