The common word in French for dental fillings is “plombage”, which may sound a little surprising since it roughly translates to “to fill with lead”. That is because if you had a cavity in France in the 18th century, a dentist would have filled it with that metal. Lead melts easily and the molten lead was poured into the cavity. Hopefully, the dentist had steady hands! Luckily, given that lead is highly toxic, dental fillings today do not contain it.
The most common kind of filling these days is composite resin, a substance applied while it’s malleable and then hardened through a polymerization process initiated by exposure to light. Still used but to a lesser extent are amalgam fillings, which contain a mixture of silver, copper, tin, and mercury. Concern about the toxicity of mercury, mostly unwarranted because the metal does not leach out of fillings to any appreciable extent, along with improvement in composite fillings has greatly reduced the use of amalgam.
What one may now consider a simple, standard procedure at your next dental appointment has a long and interesting history. One of the earliest known records of tooth fillings dates back to the ice age. Recently, researchers studied the remains of a person who lived 13,000 years ago, and whose front teeth had large holes in them, likely created by hand-held tools that were used to drill out cavities. These holes contained traces of bitumen, a derivative of petroleum, which the researchers believe to be possible evidence of the prehistoric version of modern dental fillings. Also discovered was a tooth containing traces of a beeswax filling, from a person that lived 6500 years ago in the Neolithic age.
Amalgam fillings are thought to be first used in ancient China, with the first written record of a “silver paste” being published in a Chinese medical text around 700 AD. Various combinations and formulations of materials containing silver and mercury began to be used widely in Europe and the Americas in the early 1800s. Whatever filling material was used over the ages, it was mostly for the rich. The poor simply had their decayed teeth pulled!
Caitlin Bard is completing her Bachelor of Science with a major in neuroscience at McGill University.