Oldest Known Tooth Fillings Were Made of Tar

Researchers in Italy have discovered what they think are the oldest known examples of dental fillings. When these fillings were placed 13,000 years ago, people didn’t have much ability to synthesize filling materials, so they had to go with what was handy. Although other prehistoric dentists used beeswax, these particular dentists used something a little less palatable: tar.

All That Remains

Teeth are often the only thing that remains from finds of prehistoric people. That’s because they’re harder and more mineralized than other tissues, so they don’t break down as quickly. So it’s not too much of a surprise that the two incisors are the only remains of this individual who was discovered at a site near Lucca.

What was a surprise was what researchers found when they looked at the teeth. The teeth both had holes drilled in them from the top, which ran deep into the pulp chamber. These holes had horizontal grooves on the side showing that they had been drilled out and enlarged with stone tools. Even this was just unusual for the area–researchers had discovered that people were drilling holes in teeth as much as 1000 years earlier than the current teeth were dated.

But unlike those older teeth, these teeth had another important clue in the development of dentistry: remnants of filling materials.

The old fillings were made from tar (bitumen) that had been stuffed into the hole. Researchers speculate that the tar was used as a filling material. But the filling wasn’t just tar. Inside the tar were hairs and plant fibers. Researchers believe these materials were placed at the same time as the tar. The herbs might have been for pain relief, and the hairs for strength, making it similar to a composite material.

Dental Advancements

Although bitumen is not a material we would choose to use for a filling today, it does share some basic similarities with later filling materials. First, it’s malleable, so dentists can push it into a tooth after a cavity has been drilled out, similar to amalgam or composite fillings. The material is also resistant to dissolution by saliva. And it can create a barrier against oral bacteria that would otherwise continue to invade the damaged tooth.

But obviously bitumen has many shortcomings as a filling material. It doesn’t harden the same way other fillings do. It would have to go in hot, then cool, which, we imagine, could be quite uncomfortable for the person getting the filling. Of course, it’s not like the experience of having a metal amalgam filling shoved into your tooth is particularly pleasant, either.

And then there’s the shortcoming that bitumen shares with metal amalgam: color. Tar is black, like amalgam fillings after they get oxidized.

Fortunately, we now have better, tooth-colored filling materials. Dental composites are highly durable and they create a tight seal with your tooth. Ceramic inlays are even stronger, which makes them more durable, and these match not only the color of your teeth, but the luster as well.

If you would like to learn more about your modern filling options in Scripps Ranch, please call today for an appointment at Oasis Dental Arts.