Edentulous Model Cast Upper and Lower Set

small. UPPER. LOWER. is a negative imprint of hard teeth and soft tissues in the mouth from which a positive reproduction cast or model can be formed. It is made by placing an appropriate material in a stock or custom dental impression tray which is designed to roughly fit over the dental arches. Impression material is of liquid or semi-solid nature when first mixed and placed in the mouth. It then sets to become an elastic solid usually takes a few minutes depending upon the material), leaving an imprint of person's. dentition. and surrounding structures of oral cavity. A positive likeness of the part s of the oral cavity for the purpose of study, treatment planning, and/or fabrication of final impression trays. are made from an impression of the oral tissues