Dentures

Having a general discussion can dentures be classed as an aid

Prosthetic device designed to replace teeth and their various functions so theoretically yes. In practice it will depend on the extent to which the relevant function was aided or replaced and that will surely depend on the extent of the dentures and other teeth. If they could bite; chew and swallow without the dentures then it could be problematic. If the time they took to do so was more than double then you have the beginnings of a case and similarly if they could not do so safely or reliably.

A quick search suggests this has already been chewed over (sorry, but not much :)).

https://www.rightsnet.org.uk/forums/viewthread/9446/#42699

Certainly comes into play for ESA. See https://wcainfo.net/issues/aids-and-appliances