How Invisalign Became the World’s Biggest User of 3D Printers

Joe Hogan sees a lot of smiles. When people ask him where he works, he responds with “Align Technology,” which inevitably prompts the follow up, “What’s that?” It’s the $12 billion company behind Invisalign, the hellish and expensive pieces of clear plastic worn about 22 hours a day that brute force teeth into better alignment. After months, sometimes years, the discrete rival to braces promises to give people smiles they will want to show off. Hogan gets a look at them all. And he’s eager to see more.

Align is embarking on its biggest manufacturing overhaul since it was founded by two Stanford Graduate School of Business classmates 29 years ago. The company is preparing to begin directly 3D printing the aligners at the core of its business, ditching what Hogan describes as a longer, more wasteful process that involves making molds. A successful transition could lower costs and make treatment more affordable in the long run, bringing Invisalign to more customers and boosting Align’s profits.

It also, according to Hogan, would entrench Align as the world’s biggest user of 3D printers. Hogan isn’t a founder or a scientist, though he has raised honeybees for over 25 years. He also doesn’t have a Wikipedia page, despite having run three multibillion-dollar international companies. But he’s a manufacturing veteran who knows about plastics and 3D printing, especially after over a decade at Align.

Shares of the company have tripled in price during his tenure as it outlasted failed upstarts and surged past other competition. Align handled a record 2.6 million cases last year, including a high of 936,000 kids and teenagers. Altogether, 22 million patients globally have worn Align’s growing portfolio of aligners.

The company controls nearly every step of the process. It develops the scanners that map patients’ teeth, the AI-powered software that helps doctors plan their treatment, and the boxy machines that will soon drip out aligners and retainers. On that foundation alone Hogan expects decades of growth ahead.

Last month, Hogan spoke with WIRED at Align’s lab in Silicon Valley about his predictions for the future, his tips for patients, and why he believes my recent Invisalign experience was an anomaly.

This interview has been edited for clarity and length.

WIRED: Have you ever been an Invisalign user? What's your journey with teeth been like?

Joe Hogan: I didn't know anything about teeth before I came here. I didn't even know how teeth moved your entire life. The first thing I did is I got my teeth scanned and started a treatment so I could really learn. So that was 10 years ago. I can't tell you that I always wear my retainers. My wife always wears hers. I tell my wife sometimes and I say, “Kate, you don't have to wear them every night, like every other night.” She goes, “You're not a doctor, Joe. You just run the company.” But the journey was good.

In the clear aligner market globally, Invisalign represents 60 percent to 70 percent of the market share, but within all of dentistry, where do you sit?

We're not a dental company. We're an orthodontic company. We did roughly $4 billion in revenue last year. If you look at what we measure on orthodontics, you have to measure against wires and brackets. There's no one even close. I don't want to be overly business to you, but we sell roughly $3 billion of aligners and $800 million of scanners. Then we sell roughly $3 million of retainers. So there's no other company in orthodontics that large.

What allowed you to succeed where other companies have not taken off?

It's time. We were the first ones to what I call mass customization, to be able to 3D print a million different aligners a day. It took us years to figure out how to do that. When these guys started, if they did five cases a day, they were excited. We had to take 3D printing equipment and modify it massively because most 3D printing was a prototype business at that point in time.

This team—this was before I got here—had to learn how to make these things at mass and at a scale that has never been done. I'd say we have a massive first mover advantage of not just the clinical setups, the material science, and the technical part of how you set up cases, but also the raw how you produce this at scale.

Your colleague was saying that you're probably the largest user of 3D printing machines.

Not probably. By far. [Two 3D printing industry experts tell WIRED they agree that Align prints more parts in house than anyone in the world.]

That seems crazy to me that a $4 billion business is the biggest consumer, not one of the businesses that have hundreds of billions of dollars in revenue.

That seemed crazy to me when I walked in too. That whole industry got lost because it really wasn't scaling. It was trying to appeal to a whole number of hobbyists. When I came in here, I realized that we really didn't 3D print those aligners—that we were 3D printing molds and vacuum-forming a plastic over them.

When I was growing up, people were trying to straighten their teeth to have better smiles, not necessarily resolve a medical issue. How many cases these days are for beauty versus health?

Over the last three or four years, I'd say we have many more that have to do with functionality. When I walked in, we primarily were about aesthetics, and our demographic would've been women within a certain age group.

But the industry became more aware about the long-term viability of your ability to clean teeth and having spaces between them, so you can floss on a regular basis. As you go forward, I think it'll end up being 50-50 where the younger patients will probably be worried more about aesthetics and the older patient is going to be worried about how do I maintain my teeth for life?

When I was going through the Invisalign process, I was looking at studies on the efficacy of Invisalign to understand if it is as good as braces, and it seemed like a lot of those studies were done on a narrow demographic group. What are you doing to expand the research, especially as you go into new markets around the world?

As you move into areas in the Middle East, in Asia, you see China is completely different from Japan in the sense of the way their teeth align or don't align. We had to adopt our technology around those things. What we do about being able to address these other demographics or other nationalities is we have to put a ton of money into expanding our portfolio of products. [Hogan later declined to point to specific public studies with broad racial demographics.]

You've spent a considerable time talking about teens and kids products recently. Was someone asking for these things?

If you ever saw an Essix device that they used to expand kids’ palates, I had that in 1993 with my younger kid. I remember refusing to go into his bedroom at night and turn that crank. I'd send my wife in. “You have a better way with him.” That's what a coward I am.

You walk in there with this Allen wrench, and you have to turn that thing 360 degrees. It hurts. When I came here I remember thinking about that and talking to the team. We had ideas that we could put in a palate expander every night and make that move. And so I thought what we were addressing with that is a way to … have it much easier on parents and kids than turning that screw every night.

One of the biggest frustrations, at least in the North American market, is the pricing, especially with the way dental insurance works, or doesn't work. Like the price ranges, I saw, anywhere from $3,000 to $8,000. Your average selling price to doctors is about $1,200. But help me understand the pricing.

Remember, this is a medical device that in the end, we don't set the price. We charge a doctor for that particular case, how many aligners is it going to be or whatever. A doctor decides what they are going to charge a consumer. Orthos tend to charge more for teens because they think teens are more difficult. Most of the general practitioners would primarily do adults, but some do kids and they have their own pricing structure. We set the price for our product line. It's probably in the end 25 percent of what the total price will be.

When we say that overseas we charge less, that's sometimes because they're moderate cases. They don't want to do a full case. They just want to do 30 aligners or so. The doctors can charge less too because they're not doing a full case. But orthodontics is expensive. It really is. And it takes time. It is one of the most expensive procedures that you can get.

One of our biggest costs is just shipping. We're probably one of the largest small volume shippers in the world, and it's getting to a point as we've reduced our internal costs that a lot of what we do is transportation costs. If you look at our margins, you'd say they’re margins of a good company. It does well, but not extravagant margins.

I was encouraged to eat with my aligners and warned that certain foods would stain them. Is there a way to develop a plastic that doesn't stain so you can eat anything with them in?

First of all, I would tell you, don't eat with your aligners.

You're not a doctor. I'm not trusting you.

We can't control exactly what's conveyed to patients at times. But no, I'd say that that's not a good experience. [Hogan later adds that eating with aligners could increase the risk of cavities, permanent discoloration of teeth, and compromising the fit.]

The outsides are polyurethane, very soft plastics, so it can grab your teeth and hold them. The inside’s polyester. It gives you the rigidity to move it. It's kind of an oxymoron to say, give me a product that really can move my teeth and won't stain.

Going back to 3D printing, you've said you’re trying to directly print the aligners. But it sounds like you still need to have a breakthrough in terms of a material that'll go into these machines and be able to do that.

We feel we have that material. We do. That's why we bought Cubicure in Austria. It bothered me to death that we couldn't 3D print an aligner. We tried to work with chemical companies, everyone, to make this, and we couldn't find anyone that could do this. We hired our own polymer chemist, and then over time, we figured out how to make a resin that would have the properties of our current material that we vacuum form, but be able to 3D print.

Once we had that material science done, we knew it was going to have to be high viscosity. Watery resins cannot deliver the combination of complex material properties and performance characteristics required for our applications. And that's why we bought Cubicure, because they have machines that know how to process high viscosity, performance resins. We have a resin we want, and that resin is as good or better than SmartTrack [Align’s current material]. And then we have a process to make aligners. Remember, we have to make a million of these a day. That kind of scale is monstrous, and we have a brand new process. That's what we're going through now.

But what is the scaling challenge here? Is it just making enough of the machines? Is it getting quality control?

First of all, how do you print these things to limit the amount of resin that's used on them? Do you print them vertically? Do you print them horizontally? Do you print them sideways? Where do you put the runners, where the material actually goes into? Do you put it on the outside? Do you put it on the inside? Do you put it on the label side? Do you cut it with lasers?

When we vacuum formed, all you had to do was laser the gingival area, and you were done. In this case, it's a completely different story. It's a really dynamic and incredible engineering problem. We certainly have to be efficient enough to make sure that when we go into the marketplace, that it's a profitable equation. At scale, we should get to a point where the resin is less expensive and that will help. But that takes years.

Should people be worried about chewing microplastics?

No, we've never had one complaint about microplastics since I've been here. If you do enough research, there’s a lot to be learned on what's real and what's not real, what's toxic. There's so much plastic use in medicine, and it's all over the place. Water. All these plastics have different compositions. When we start to look for a plastic that you're going to wear, we don't use any components that have any degree of toxicity, so that we know when we move into FDA approval or regulatory approval of it, we know we're good. We didn't put anything in there that would be considered toxic.

On the treatment plan, one thing that I would've loved is a way to know which aligner was going to be most painful. Was this week going to be a painful week or a not painful week?

That's funny. I just had another person tell me the same thing. My son told me that, Tyler.

Great minds think alike. It seemed to me that AI should be able to solve that if you collect enough data. There were some weeks that were like, I can eat anything, do anything. It's great. And other weeks I wanted to punch a wall.

I've actually talked to Srini [Kaza, Align’s executive vice president for research and development] about it. He looked at me cross-eyed the first time I told him. But now that I have two data points, I can draw a line through it.

Really, I think it's viable and it's not like it's a big deal for us. We know when a massive movement's coming that's going to upset you. And we know the delicacy of certain teeth that will be affected.

In terms of efficacy, one thing that I noticed was you said “touchup cases” shipped last year were over 136,000, which was up 36 percent. Isn't that bad? Shouldn't you be doing less touchup cases?

That touchup is when someone didn't wear the retainers and the doctor said, “Oh, I have to touch that up because you got some lower crowding or whatever,” and they'll order anywhere between five and 10 to 15 aligners.

There's also a lot of passion, excitement right now in the country for bringing back manufacturing to the US. You’re in Mexico, Poland, and China currently. Is it ever going to be viable to make aligners in the US?

It could be. Labor is a huge component. As we get to manufacturing that's much more automated, having it in the United States could make sense. We'll certainly look at that as the time comes. Because I do think that, again, that shipment cost that we talked about, there is a piece to that, too.

How many people does it take to make these in Juarez, Mexico right now?

Thousands.

That seems crazy. Isn't it just a machine doing all these things?

Oh my goodness, 3D printing at this level is a monster. You can 3D print these things, but remember, you have to take these aligners and you have to put them in bags. Sometimes, you have to treat them in some way. It's hard to explain, but it looks like the inside of a Costco in a lot of ways.

But we're not talking about an iPhone. This seems so simple relative to something like an iPhone that has hundreds of components.

It does seem simple, but it's a very sophisticated process, too. We have centrifuges that are used to recapture resin. We have washing stations. You’re 3D printing and then your vacuum forming. Lots of software engineers down there as well. It sounds easier than what it is. But I do think as we direct 3D print, there'll be less of a labor component to it.

Look, I'm a US citizen. If I can support the country, I'll support it. But I feel like NAFTA's been a help over the years. We just want to do what makes sense for the business.

The other thing in politics right now, you mentioned the FDA. Do you even view that as a valid stamp of approval at the moment?

I do. In general, at a certain level, the FDA is very competent. Most of the argument with the FDA today has to do with vaccines. That's above my pay grade. As far as how we interact with the FDA, how they test our materials, that hasn't changed. I feel it's good and adequate. I've worked across a lot of administrations, and I haven't seen it change dramatically, which I think is great. The whole question on vaccines, I leave that to people that are smarter than me, which is a large group of people.

Do you think traditional metal braces ever go away?

I can't predict that. We can do everything wires and brackets can do. We can do it faster, and I think we can do it in a way that's more comfortable for patients. But patients are going to have to make that decision. We'll do everything we can to convince them. I can't imagine 20 years from now, you still have metal and wires on people's teeth, because it's really not needed. But there might be people that think that they'd rather have wires and brackets or doctors only want to work with that. And I'm all for free choice.