One of these are Cribbin's Teeth. For those of you who don't recognise the name, Cribbins was Most Von Lipvig's old companion who shows up and tries to blackmail him in Making Money:
Making Money wrote: It was Cribbins! It could only be Cribbins!
Moist's memory sandbagged him, one bag after another. The teeth! Those damn false teeth! They were that man's pride and joy. He'd prised them out of the mouth of an old man he'd robbed, while the poor devil lay dying of fear! He'd joked that they had a mind of their own! And they spluttered and popped and slurped and fitted so badly that they once turned round in his mouth and bit him in the throat!
He used to take them out and talk to them! And, aargh, they were so old, and the stained teeth had been carved from walrus ivory and the spring was so strong that sometimes it'd force the top of his head back so that you could see right up his nose!!
According to What The Victorians Did For Us, beginning in the Victorian era diets became sweeter and tooth decay started becoming a major problem. At the same time ether allowed rotten teeth to beremoved without pain. This led to the invention of dentures.
The first dentures were known as "Waterloo Teeth". They were made of real human teeth (some of them from Waterloo victims, but most from robbed graves) which were set into ivory "gums" carved out of hippo jaws. Because they never fitted well, they were held in place by springs which pushed the upper and lower teeth apart and would, occationally, shoot the dentures out of the mouth!
I wonder if this might have represented a secondary income for un-ethical priests in the catacombs...
Apparently wearing dentures were so stylish and modern that some people just had all their teeth pulled out to save and pain time later on.