An orthodontic plaster cutter is a specialized tool used in orthodontics to cut or shape plaster models of a patient's teeth and oral structures. These models are used to create custom orthodontic appliances, such as retainers, aligners, and expanders. Orthodontic plaster cutters are usually manual and have a sharp blade that can cut through the plaster quickly and cleanly. Some orthodontic plaster cutters also have features that help measure and mark the plaster model before cutting.