Impression materials Any substance or combination of substances used to record an impression or negative reproduction those are called as impression materials. Impression technique A method and manner used in making a negative likeness. Classification 1. Based on material use A. Inelastic or rigid Impression plaster Zinc oxide eugenol Compound
Introduction The term instrument refers to a tool, device on an implement uses for specific purpose or type of work and is preferred in profession or scientific field as precision items are generally required to perform specific procedure. G.V. Black Classification is first acceptable nomenclature and classification for hand instrument.