The Toothache That Ended in a Small Explosion

Before modern dentistry settled into predictable routines, a trip to the dentist's chair in the 1800s could end in genuine terror. Patients with severe, throbbing toothaches sometimes reported sensations no one could explain. Doctors scribbled down their accounts, unsure what they were even witnessing.

In 1871, a dentist named J. Phelps Hibler published a case in the journal Dental Cosmos that still startles readers today. He described a young woman whose molar suddenly burst with a concussion and report loud enough to nearly knock her off her feet. The blast left her temporarily deaf for days afterward.

Hibler wasn't describing a one-off fluke. Similar reports appeared throughout the century, with patients describing a sharp crack inside their own mouths, followed by sudden relief from the pain that had tortured them for days. Doctors at the time had no modern diagnostic tools to make sense of it.

Early physicians floated a theory involving mysterious internal gases building up inside the tooth itself, like a tiny pressure cooker waiting to pop. It sounded plausible enough for the era, but it never fully explained why the explosions happened to some patients and not others.

Modern dentists and historians now believe the real cause was far stranger than trapped gas. Dentists of the time often filled cavities using mismatched metals like lead, tin, and silver, without understanding the chemistry involved. Those combinations weren't inert once they sat inside a mouth.

Inside a decaying, acidic tooth, those mismatched metals essentially formed a tiny battery. Saliva acted as an electrolyte, and the chemical reaction slowly generated hydrogen gas trapped beneath the filling with nowhere to escape.

Eventually, the pressure had to go somewhere, and it went out with a literal bang. Standardized mercury amalgam fillings in the 1920s quietly ended the era of exploding teeth, closing one of dentistry's strangest and least-discussed chapters for good.