CHEMICAL PRODUCTS FOR INDUSTRIAL USE-NAMELY, PLASTICS IN THE FORM OF PASTES OR POWDERS AND MATERIALS MAINLY CONSISTING OF PLASTICS IN THE FORM OF PASTES OR POWDERS FOR TOOTH CROWNS, TOOTH BRIDGES, ARTIFICIAL TEETH AND PLASTIC PROSTHESES; PLASTICS FOR USE AS MODELLING MATERIAL FOR DENTAL PURPOSES, IMPRESSION MATERIAL FOR DENTAL USES, DENTAL FILLERS, DENTAL LACQUERS, INSULATING MATERIAL FOR DENTAL USES, SUCH AS GYPSUM MODELS FOR THE MANUFACTURE OF PLASTIC TOOTH PROSTHESES; DRYING AND CLEANING M...