Humans have always been plagued by toothaches, with reports of tooth infections dating back to ancient times. The Chinese thought they were caused by a worm living inside the tooth, a theory thatpersisted until the mid-18th century. Treatment involved killing the supposed worm with arsenic, a chemical that was used until the 1950s. The ancient Greeks destroyed the pulp of an infected tooththrough a variety of methods, including inserting a hot needle or a probe dipped into boiling oil.
Dental anthropologists have traced what may be the oldest root canal procedure (albeit a primitive one) to an ancient Roman soldier living in the Negev Desert (present-day Israel) in the 2nd or 3rd century B.C. A tooth in the telltale skull found in the 1980s contained a thin bronze wire in its pulp chamber, which the scientists believe was likely used to treat an infection there. Before this discovery, the earliest root canals were thought to have been done in the 17th century.
Over the centuries, various other crude techniques were used to destroy diseased tooth pulp, including pounding a tapered orangewood or hickory stick dipped in carbolic acid or creosote (which acted as antiseptics) into the tooth with a mallet, leaving it there for a few seconds, and then pulling it out, along with the pulp. Needless to say, these procedures were extremely painful, but when arsenic was poured into the tooth before the pulp was removed—as the ancient Chinese had long been doing—the procedure became painless (though very damaging to adjacent tissues).
It wasn’t until the early-to-mid 19th century that many tools and materials needed for performing a root canal were developed or adapted (such as from a watch spring). Among the materials used to fill the canal after the pulp was removed were gold foil and wooden plugs. The standard filling material today, gutta-percha, was first used in 1847. And the first sheet of rubber—the predecessor of today’s dental dam—was introduced in 1864.