The upper tray is of gilted bronze, probably French, and is originally from the Charrierie, Collin and Gentile collection, made in about 1840. The other is porcelain, probably English and inscribed 1861. Impresion trays of this type are filled with a soft putty and inserted into the patient's mouth. An impresion is made, which is then used as a model for a set of dentures.
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