Dental Curing Flask

Circa 1880s

Porcelain teeth, rather than being held in place by pins and soldered to a denture’s cast metal base, were inserted into the upper or lower denture while it was cradled within the lower half of a metal dental flask. Strips of prepared rubber material were packed into the mold, and the upper half of the dental flask screwed down tight. The flask and its contents were steam-heated under pressure in a vulcanizer oven. 

Initially, the rubber became soft enough to fill the mold crevices and surround the porcelain teeth. With additional heating, the rubber continued to cure, becoming vulcanized. Ideally, the process made a denture with teeth securely fixed in a fully hardened but flexible plate and gums.

Vulcanite as a denture material had its disadvantages for the patient. Being porous, when improperly cured it succumbed to the moist environment of the mouth, becoming discolored and foul-smelling over time. Despite the dangers of its curing and the shortcomings of its use, vulcanite remained the denture material of choice from the mid-1800s to the 1930s.