Most people associate the name Gaten Matarazzo with the series Stranger Things and the character of Dustin—the curious teen with curly hair and a trademark smile. Many viewers also noticed that Gaten and his on-screen character have unusual teeth, slightly different facial features, and distinctive shoulder movement. This isn’t a makeup trick, but a sign of a real genetic condition Gaten lives with: cleidocranial dysplasia, a rare disorder that affects bones and teeth. It isn’t life-threatening and doesn’t affect a person’s intelligence.
Because Gaten speaks openly about his condition and the show’s creators worked it directly into the storyline, many everyday viewers first learned about cleidocranial dysplasia on a larger scale. His story shows that even a challenging diagnosis doesn’t have to define a person—it can become a catalyst to help others.
Who is Gaten Matarazzo, and how his diagnosis made it onto the screen
Gaten Matarazzo was born in 2002 in New Jersey, USA, and became widely known as Dustin Henderson in Netflix’s Stranger Things. As early as the first season, in one scene you can hear Dustin explain to the bullies that his teeth are delayed because he has “cleidocranial dysplasia.” That line wasn’t random—the writers took it straight from Gaten’s real life.
According to an interview at Rutgers University, Gaten had issues from childhood with baby teeth that wouldn’t fall out and adult teeth that didn’t come in. He also had extra—so-called supernumerary—teeth that dentists had to surgically remove. These difficulties are why his appearance changes from season to season—at one point he’s missing teeth, then he wears dental prosthetics, and later things change again depending on both the storyline and his real-life situation.
The show’s creators chose not to sideline Gaten or hide what makes him different; instead, they incorporated it into the character. Thanks to that, Dustin became not only a fan-favorite “geek,” but also one of the first major TV characters to openly mention a rare genetic disorder.
What is cleidocranial dysplasia?
Cleidocranial dysplasia (CCD) is a genetic condition that primarily affects the development of bones and teeth. The name refers to the collarbones (“cleido”) and the skull (“cranial”), which nicely describes the parts of the body most noticeably affected. In people with this condition, the collarbones can be weakened or even absent, and the skull develops more slowly and differently than in the general population.
According to expert sources, it’s a rare disorder—its prevalence is estimated at about one person in a million. Many cases may go undiagnosed, however, because symptoms can be very mild. Even though it’s a visible disorder of the skeleton and teeth, cleidocranial dysplasia doesn’t affect intellect, and with appropriate treatment patients have a normal life expectancy and a good outlook.
Doctors classify it as a congenital genetic disorder, meaning a person is born with it. The first signs are often noticed by pediatricians or dentists—fontanelles (soft spots on the head) that don’t close, an unusual skull shape, or delayed eruption of permanent teeth.
How cleidocranial dysplasia presents
Symptoms of cleidocranial dysplasia can vary widely—some people have only mild changes, while others have more pronounced signs. In general, it’s a combination of skeletal and dental differences that are relatively easy to recognize on closer inspection.
The most typical areas include:
- Collarbones and shoulders – the collarbones may be shortened, underdeveloped, or missing entirely. In practice, this can mean a person can pull their shoulders unusually close together in front of the chest—something we see in Stranger Things as a “trick” Dustin shows his classmates.
- Skull and face – in children, fontanelles (soft spots) may remain open for a long time, the skull sutures fuse later, the forehead may be more prominent, and the nose flatter. The upper jaw can appear narrower, and the eyes may seem slightly wider set.
- Build and limbs – some patients are a bit shorter than other family members and may have broader thumbs, shorter fingers, or mild spinal differences such as scoliosis.
- Teeth – this is one of the most common and most challenging areas. Baby teeth fall out late, permanent teeth erupt late, extra (supernumerary) teeth can be present, and the bite may be crowded and irregular.
In addition, some patients have more frequent sinus and middle-ear infections, which can also lead to hearing loss. Young children may have mild delays in motor development—for example, they may walk or climb later—but their mental abilities are fully preserved.
The cause: the RUNX2 gene and inheritance
In most cases, cleidocranial dysplasia is caused by a mutation in the RUNX2 gene. This gene contains the “instructions” for making a protein that is crucial for the development of bones and teeth—it helps regulate the activity of cells that become bone-forming cells (osteoblasts). If one copy of this gene doesn’t work properly, the body doesn’t produce enough functional protein, resulting in the typical features of cleidocranial dysplasia.
The condition is inherited in an autosomal dominant pattern. In practice, that means if one parent has cleidocranial dysplasia, each child has about a 50% chance of inheriting the mutated gene—and therefore the condition. At the same time, in some cases the mutation arises completely spontaneously, with no previous family history; this is called a “de novo” mutation.
Interestingly, even within the same family, people carrying the same mutation can have symptoms of very different severity. One person may have only mild skeletal changes and small dental differences, while another may need dozens of procedures from dentists and orthopedic specialists. That’s why the diagnosis can sometimes be missed until adulthood.
Treatment and living with cleidocranial dysplasia
Cleidocranial dysplasia can’t be “cured” in the sense of fixing the RUNX2 gene so bones develop like they would in someone without the condition. Modern medicine, however, can manage the individual symptoms very effectively, so most patients can lead full lives.
Treatment is always individualized and often involves a whole team of specialists—a pediatrician, orthopedist, geneticist, dentist, orthodontist, maxillofacial surgeon, ENT doctor, and physiotherapist. For skeletal differences, surgical correction is sometimes recommended; for skull-related issues, young children may need a special protective helmet. For hearing problems, ear tubes or hearing aids can help.
The most demanding part is usually dental and jaw care. Repeated surgeries are often needed to remove extra teeth, help permanent teeth erupt, followed by orthodontic treatment with braces and, in some cases, dental prosthetics. It’s a process that can take all of childhood and into adulthood, and in many countries it can be a significant financial burden for families—easily adding up to thousands or tens of thousands of euros.
Even so, the overall outlook for cleidocranial dysplasia is very good. With proper care, patients have a normal life expectancy and can study, work, play sports, and build careers much like people without the diagnosis.
Gaten Matarazzo: personal experience with the diagnosis
Gaten Matarazzo has never really spoken about his condition as a “tragedy,” but rather as something he has to learn to live with. In an interview for Rutgers University, he said that as a child he felt different when he saw classmates had all their teeth while he was still missing his upper front teeth. He also had extra teeth in his gums that had to be removed surgically over time, and he endured years of dental procedures.
He has said that finding dentists who had experience with cleidocranial dysplasia wasn’t easy. Some surgeries lasted for hours and removed several teeth at once, while other procedures focused on helping permanent teeth erupt properly. These experiences are indirectly present in the show—Dustin’s “disappearing” and reappearing teeth aren’t just a visual joke, but reflect the real course of Gaten’s treatment.
School is a separate chapter. Many children with visible differences experience bullying and teasing, and it was no different for Gaten. In Stranger Things, we see Dustin become a target of ridicule for his appearance and speech, but the response of his friends—acceptance, support, and humor—shows how important a role the people around you play. Today, Gaten often emphasizes that being open and explaining the diagnosis to others helped him get rid of shame and make it “just another part” of his identity.
How the diagnosis influenced his career and the character of Dustin
At first, cleidocranial dysplasia made it harder for Gaten to start an acting career—in his teens, without front teeth and with an atypical facial profile, he didn’t fit the usual Hollywood idea of a “perfect” teenager. In the end, though, it turned out that his difference was exactly what made him memorable and authentic.
After casting Gaten, the creators of Stranger Things even reworked the character of Dustin to reflect his real diagnosis. In one of the first scenes, Dustin stands up to the boys bullying him and explains that he has “cleidocranial dysplasia.” For many viewers with the same condition, that moment was the first time they “saw themselves” on screen—suddenly they heard the name of their diagnosis in a popular series, not only in a doctor’s office.
Importantly, Dustin isn’t defined by his diagnosis. He’s a smart, inventive kid who loves science experiments, Dungeons & Dragons, and talks exactly as things come to mind. In the story, cleidocranial dysplasia is more of a detail that explains his appearance and some gags, but it doesn’t cast him as a “sick” or “tragic” hero. That’s also why many experts point to Stranger Things as an important example of inclusive representation of people with rare conditions.
CCD Smiles: when an actor uses his fame to help others
Gaten Matarazzo didn’t stop at talking about cleidocranial dysplasia in interviews. Together with his family and advocate Kelly Wosnik, he helped support the creation of the nonprofit organization CCD Smiles, which focuses on improving the lives of people with this diagnosis. The organization was founded in response to the fact that many patients face years of painful dental procedures, demanding surgeries, and often high costs that insurance doesn’t always recognize as “medically necessary” treatment.
CCD Smiles provides information about the condition, connects families with specialists, supports research, and offers a space where people with cleidocranial dysplasia can share their experiences. On the website you can find ways to request help, patient stories, and scientific information about the diagnosis. The fact that Gaten Matarazzo is one of the organization’s public faces helped bring the topic into the media and also motivated Stranger Things fans to learn more about the condition.
Together with the series, this created an interesting effect: fiction and real life came together with a shared goal—to show that even with a visible genetic condition, you can be successful, confident, and also change other people’s lives for the better.
Video: Gaten Matarazzo speaks openly about his condition
If you want to hear Gaten talk about cleidocranial dysplasia in his own words, it’s worth watching interviews and features where he explains the topic in more detail. In the following video, he shares his experience with the diagnosis, bullying, and dental surgeries, and explains why speaking up about the condition matters to him.
What we can take away from Gaten Matarazzo’s story
Gaten Matarazzo’s story shows that a health-related difference doesn’t automatically hold someone back from doing what they love. In his case, cleidocranial dysplasia became part of a unique look that directors and audiences remembered, but also a topic he speaks about openly and tries to destigmatize. What used to be a reason for ridicule is now becoming a source of strength and a platform for helping others.
From a medical standpoint, it’s important to know that while cleidocranial dysplasia can mean long-term and expensive care, with proper management it doesn’t prevent a full life. Families who encounter the diagnosis should seek genetic counseling, a team of specialists, and shouldn’t be afraid to ask about all treatment and support options—either within their healthcare system or through organizations such as CCD Smiles.
And finally, there’s a social dimension. Characters like Dustin Henderson make visible people who previously almost didn’t exist in popular culture. Thanks to that, the name “cleidocranial dysplasia” no longer appears only in specialist articles and genetic counseling offices, but also in conversations among TV fans and on social media. That, too, is a small but important step toward seeing people with visible differences not through the lens of pity, but of respect.
Sources
- Cleveland Clinic – “Cleidocranial Dysplasia”
https://my.clevelandclinic.org/health/diseases/24090-cleidocranial-dysplasia - MedlinePlus Genetics (NIH) – “Cleidocranial dysplasia”
https://medlineplus.gov/genetics/condition/cleidocranial-dysplasia/ - Rutgers University – “Stranger Things Star Gaten Matarazzo Talks About His Rare Genetic Condition With Dental School Dean”
https://www.rutgers.edu/news/stranger-things-star-gaten-matarazzo-talks-about-his-rare-genetic-condition-dental-school-dean - CCD Smiles – “About”
https://ccdsmiles.org/about/
Jana
I like turning curiosity into words, and writing articles is my way of capturing ideas before they slip away — and sharing them with anyone who feels like reading.
