5 Materials for dental prosthesis, included in this class, namely, materials for crowns and bridges for dental use and for oral prophylaxis, in particular discs made from ceramics, from metals or metal alloys or from plastics as blanks for the fabrication of dental restorations; materials for facing artificial teeth and teeth prosthesis, in particular metal ceramics, dental ceramics and dental restoration compounds of plastic; dental restoration compounds of metal, precious metals and dental alloys thereof as well as ceramic masses and plastics for dental restoration use; dental fillers for teeth, dental filling materials, materials for sealing teeth and veneering materials for dental use, composite materials for model preparation and model processing composite materials for dental use; modeling materials, in particular waxes for dental use; dental impression materials, duplicating materials, namely, orthodontic alginate for dental impressions; investment materials, namely, materials for repairing dental crowns and bridges and fixing materials for dental use, namely, material for repairing teeth