In the ongoing Truth storyline currently underway in Action Comics, Superman has a new power in his arsenal: the ability to hear radio waves. While the caped hero had to expose himself to a huge dose of kryptonite to gain this ability, many IRL humans claim to have achieved it by other means — namely, going to the dentist.
The hypothesis that dental fillings can pick up radio waves and render them into intelligible sound remains unproven but persistent. No, our mouths aren’t radios, but radios are startlingly simplistic machines.
The idea of the accidental radio implant seems to endure because it makes a surface sort of sense: Radio waves interact with metal and humans hear jawbone vibration. It also has (or had) a celebrity spokeswoman in Lucille Ball, who talked all about her condition on The Dick Cavett Show in 1974, retelling a story in which “[the] music was getting louder and louder, and I realized it was in my mouth!” A similar, fictionalized scene played out in an episode of Gilligan’s Island where Gilligan’s mouth turns into a radio receiver after he’s hit in the head. For whatever reason, people were really into this in the ’60s and, since then, there’s been an aggregation of anecdotal evidence online.
All of these stories suggest that the body can act as a sort of antenna for radio waves, and the mouth’s metallic fillings can translate those waves into some type of sound.
Here’s the part that makes sense: You have your radio signals, which are transmitted by, say, a local radio station and picked up by antennas all over the region. In theory, a receiving antenna can be any metal or conducting substance, including, yes, a metal filling. The conductive, which is to say water filled, body of a human might legitimately amplify a filling’s ability were a person to stand close enough to a transmitter.
Picking up the radio signal is the conceptually easy part. But to actually turn those radio waves into sound, you need two other elements: a demodulator, which turns the radio waves into an actual audio signal that we can hear, and a transducer, which acts as a speaker. The human jaw can potentially pull of the latter trick so demodulation is the real issue here. How is audio information being pulled out of a radio wave by a filling? Realistically, it’s not. Though it’s possible that a filling could pick up a signal and that a human might feel or hear that signal on some level, it is profoundly unlikely that anyone could get the latest Taylor Swift jam through a molar. This, alas, is where the theory loses its legs.
Superman remains, like Lucille Ball, super.
Could our bodies receive radio waves? Sure. Might those waves cause our crappy metal dental work to vibrate? Probably not, but it’s not impossible. But most importantly, would we be able to make out actual sounds or music from those vibrations? Absolutely not — that’s where kryptonite comes in.