Dakota Johnson Says Her Tooth Gap 'Closed By Itself'—But Can That Really Happen?

It's been a few days since the internet began mourning Dakota Johnson's recently closed tooth gap—and in the face of rumors that the actress had dental work done, Dakota came clean about what really happened to her signature smile.

During an interview with Jimmy Fallon on Tuesday's episode of the Tonight Show, Johnson, 29, said that the change wasn't necessarily planned. "I had a permanent retainer since I was 13 and it was just glued to the back of my teeth," Johnson told Fallon. "I was having a lot of neck problems recently, so my orthodontist decided it would be a good idea to take it off and see if my jaw expanded."

Apparently removing the retainer helped her neck pain—at the expense of closing her tooth gap. "My gap closed by itself and I’m really sad about it, too," she said, referencing those who came out in droves on social media to mourn her loss. (Seriously, a Twitter user even made a "Celebration of Life" video for her former tooth gap).

Anyway, sad news I guess (not really—Johnson herself even commented, "The fact that this is a newsworthy event in our world right now is pretty sha-ka-khan to me," which, hard agree). But it got me thinking: How much do your teeth really shift throughout your life—and how quickly can it happen, say, if you take your permanent retainer out? (Or, for my fellow nightly retainer wearers, if you forget to wear them for a while.)

Johnson gave her own, uh, medical reasoning as to why her gap closed: "As you grow as a human being, your skull expands and your jaw and your teeth move," she continued. "Your teeth don't look like they did when you were a baby." And yeah, I can see where she's coming from—but what do actual doctors of dental medicine and surgery have to say?

Apparently, Johnson's right: Our teeth definitely move throughout our lifetimes. That's because teeth are essentially set in bone, and bone is alive, which accounts for all of that movement, says Matthew Messina, DDS, an associate professor at The Ohio State University College of Dentistry and a consumer advisor for the American Dental Association. "We tend to think of our teeth as being set in cement, but they're not," says Dr. Messina.

He says it sounds like Johnson had a bonded retainer—and when that retainer was removed, her teeth drifted into a more comfortable position. It just so happens that her teeth wanted to move closer together than farther apart. "It's hard to predict in advance what kind of motion [the teeth] will have," says Dr. Messina.

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And as for all of my fellow nightly retainer-wearers out there, your teeth may also move if you take your retainers out. As far as the question of "How long will I have to wear my retainers?" goes, Dr. Messina says he has to answer that question with another question: "How long do you want your teeth not to move?" (Sorry to be the bearer of bad news—it sounds like you and I will be wearing our retainers until we lose them or until we get sick of them; whichever comes first).

But another interesting part of Johnson's story, according to Dr. Messina, is the connection between her jaw and the rest of her body. "Neck pain, shoulder pain, and back pain are very common problems with TMJ ( the temporomandibular joint, which connects the jaw to the skull)," he says. "If someone's bite is out of alignment, those are very common problems."

The good news, for Johnson at least? The gap can return. "It's gonna come back" Johnson told Fallon—and she's also right about that. "Moving it back is orthodontics—whether that means braces or wires or computer-generated retainers," says Dr. Messina. "Especially if there are models of her teeth before, so if we know where she came from, it's just a matter of recreating an appliance for recreating the space."

Looks like Johnson's tooth-gap fans can breathe a sigh of relief. But for the rest of us retainer-wearers, if you like your teeth where they are, make sure you keep that retainer in there or at least don't lose it.

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