Time-saving occlusal rims for dentists or technicians. Straight blocks are a large size with a curved base to fit the model. Blocks can be easily adapted to shape and carved with a wax knife when warm, and maintain contour when cooled. Using preformed blocks prevents the risk of porosity which may occur when sheets of wax are hand-rolled. Precurved blocks are designed to represent the tooth position and are even quicker to use.