A denture is a removable solution to filling the gaps made by losing teeth. They can either be partial denture if only a few teeth have been lost, or full dentures if all the teeth in one or both jaws have been lost
Full dentures are usually made of plastic, but partial dentures can be either made of plastic or a metal alloy. A partial denture would usually require clasps are the natural teeth and these can be visible in the smile.
Plastic partial dentures are less expensive to make. But unless they are designed very carefully they can damage the teeth they fit against. You can also get flexible plastic dentures. These dentures do not need clasps as they are held in place by flexing against your natural teeth. Metal partial dentures are usually from an alloy of cobalt and chromium and they are much stronger. They are lighter to wear and can be supported by the remaining teeth. Although the base is metal, they have gum-coloured plastic and natural-looking teeth fixed to them. They are more expensive than the plastic ones.