Every night before bedtime, my daughter tilts back her head so that a pair of metal plates inside her mouth can be cranked apart another quarter of a millimeter. We turn a jackscrew with a wire tip; it spreads the bones within her upper jaw. At times she groans or even cries: she says that she can feel the pressure up into her nose.
This is normal. My daughter is 9 years old. She has a palate expander.
So does her best friend, and, by her count, so does nearly one in four of the kids in her fourth-grade class. On Reddit’s r/braces forum, a practitioner based in Frisco, Texas, said he was surprised by “how many parents ask me, ‘Hey, does my child need an expander? Everyone else seems to have one.’” His colleagues seemed to notice something similar. “Everybody’s being told they have a narrow jaw, and everyone’s being given an expander,” Neal Kravitz, the editor in chief of the Journal of Clinical Orthodontics, told me.
A generation ago, getting braces was a rite of passage into seventh grade. Today, the reshaping of a child’s smile may commence a few years earlier, at 7, 8, or 9 years old. At that point, the two sides of the upper jawbone haven’t yet joined together, a fact that is propitious for a different orthodontic process: instead of straightening, expansion. During this phase of life, when kids still have some baby teeth, a tiny dungeon rack may be wedged between a child’s upper teeth, then used to spread her upper jaw and—proponents say—introduce essential room for sprouting teeth.
The expander is an old device; debates about its use are hardly any younger. What seems to have been the first expander was described in 1860, in the journal The Dental Cosmos, by a San Francisco dentist named Emerson Angell. He wrote of “an apparatus, simple and efficient,” that he’d placed into the mouth of a young patient. Then he’d told her to expand it, day by day, by advancing a central screw—just as my daughter does today. But the journal’s editors were skeptical of Angell’s work. We “must beg leave to differ with the writer in the conclusion arrived at,” they announced in a prefatory note, foreshadowing a long disagreement within the field.
This concerned the merits of expansion versus those of extraction—whether a child’s jaw should be broadened to accommodate her teeth, or whether certain teeth should be pulled to accommodate her jaw. Around the turn of the 20th century, the influential orthodontist Edward Angle favored jaw broadening; he believed that all children should have their teeth intact, nestled in a capacious jaw, as exemplified by a human skull that had been ransacked from an Indian burial mound not far from where he practiced, which he called “Old Glory.” A few decades later, though, orthodontic research found that expanded jaws might still “relapse” into a narrow shape. By the 1970s, pulling teeth became the rule, Daniel Rinchuse, a Seton Hill University professor of orthodontics, told me.
This consensus was itself short-lived, he said—not because the field had come across some new and better mouth-expanding tech but because of fears about the supposed ill effects of doing too many extractions. Some dentists claimed that what was then the standard approach in orthodontics could even lead to painful disorders of the temporomandibular joint, or TMJ. In the face of these concerns, expanders made a comeback.
Eventually, some orthodontists started claiming that expanders had another major benefit—that prying open a child’s palate could improve her breathing and prevent sleep apnea. Some now recommend this airway-focused intervention not just for kids my daughter’s age but for toddlers too.
The basis for the trend was never really scientific, though. “Do expanders prevent obstructive sleep apnea? In capital letters: NO WAY,” Kravitz said. “There are endless research papers on this stuff.” The problem isn’t that expanders have no value, he continued; it’s that they’re clearly overused. According to Rinchuse, who co-edited the book Evidence-Based Clinical Orthodontics, the idea that extracting teeth will lead to joint disorders has never been proved. Indeed, no “high-quality evidence” supports expansion of the upper jaw for any reason, he said, except in cases where a child has been diagnosed with posterior “crossbite.” He said that, overall, orthodontic practice is less constrained by evidence than other fields of health care are, because the ill effects of bad decisions will be slight. As he put it, “In orthodontics, no one dies.”
Steven Siegel, the current president of the American Association of Orthodontists, acknowledged that some practitioners may be inclined to put a rack on every child’s palate: “There are some abuses,” he told me. But he also argued that the recent increase in expander use hasn’t really been dramatic, and that for the most part, the devices are used to positive effect. For people with a narrow jaw and crowded teeth, he said, expanders can prevent the need for extractions down the road; some kids, at least, could see improvements in their breathing. When I noted that I’d heard the opposite on both counts from Kravitz and Rinchuse, he responded that they simply disagreed. “I have great respect for both of them,” he said. “I would say that there is a controversy.”
For the record, my daughter is delighted by the treatment she’s received: In a recent family interview, conducted over breakfast, she described her course of orthodontics as “cool and fun.” Her orthodontist (who happens to be a former high-school classmate) has been thoughtful and communicative, and I’ve recommended her to several other families. Still, despite the fact that no one dies from orthodontics, one might also choose to avoid a treatment that costs several thousand dollars, has disputed benefits, and may cause modest pain—not to mention any moral injury that may accrue from tilting back your daughter’s head and cranking open metal plates to wrench her face apart.
And despite whatever caused expander mania, its existence can be jarring for a parent who grew up in the prior era of orthodontics. Indeed, the period during which this trend developed—from, say, the late 1980s until the early 2020s—happens to coincide with the stretch that intervened between my own entry into middle school and my daughter’s. For my fellow members of this cohort, expansion of the fourth-grade palate appears to be a strange and sudden social norm. During one visit to the orthodontist, my daughter and I found a handful of children about her age seated in a line of dental chairs, with technicians leaning over each of them to turn the screw of their expander. It was like we’d all gathered there for some initiation rite for children of the tribe that dwells on Cobble Hill in Brooklyn—a ritual of widening.
Not long after that, I called up Luke Glowacki, an anthropologist at Boston University who co-directs a research project in Ethiopia’s Omo Valley, where body modifications—and dental modifications in particular—are not uncommon. He told me about social groups there and elsewhere in which a child’s teeth might be filed down to points or a person’s lower lip stretched out with a plate.
Is orthodontics any different? It presents itself as curative and scientific, but many orthodontists’ websites are replete with beauty claims as well: An expander may “protect your child’s facial appearance” or provide “enhancement to the facial profile.” Siegel said that a broadened palate gives “a more aesthetic width of the smile.” Kravitz said that it could help shrink the unattractive gaps inside a person’s cheeks—“dark buccal corridors,” in the language of the field.
In East Africa, dental and other body modifications carry similar ambiguities of purpose. Filing down a person’s teeth, for instance, or removing them altogether “may also be done for ostensible health reasons,” Glowacki said. Some body-modification rituals could be understood to ward off harmful spirits, for example. In other words, they’re prophylactic. Glowacki also told me about a Nyangatom woman he knows who has scars carved into both her shoulder and forehead. The former are purely decorative, but she’d received the latter on account of being sick.
Glowacki is a parent, too, and I asked him whether his training as an anthropologist affected how he thought about expanders or other anatomical procedures, such as ear piercing, that are carried out on children in the United States at industrial scale. “You’re not gonna find any society in the world that doesn’t modify their body in some way in accordance with their ideas of beauty or of health,” he said. “We’re doing what societies all over the world do.” If now I’ve paid an orthodontist to reshape my daughter’s mouth, maybe that’s just human nature.