Dan,
We worked on a site in southern Illinois in 1995 which turned up
two sets of dentures, one had a vulcanized rubber palate and the
other was just a porcelain upper incisor. I talked to a local dentist
here in Chicago who is a specialist in historic dental stuff and got
a couple of references. Vulcanized rubber began to be used in the
1860s for dentures. We were able to date the one that we had to
somewhere around 1870. The closure date for our cemetery was
1872, so we knew the upper limit, and the style of the dentures
indicated the bottom limit. The dentist's name is Richard Glenner
and I'm sure he'd be thrilled to talk to you about the materials.
Let me know if you find out anything more,
Diane Houdek
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