Artificial teeth; dental crowns and bridges; [ dental implants; ] dental prostheses [ ; dental handpieces; dental pins for artificial teeth; dental X-ray film duplicators; dental X-ray mouth props and dental X-ray film hangers being structural parts of X-ray appliances for dental use; dental moulding apparatus, namely, dental impression trays; dental articulators; denture parts, namely, dental clips for securing pre-existing dentures ]