Investors who want to put their money where their mouths are can do so literally with two stocks. Align Technology Inc. (NASDAQ:ALGN) is the leader in clear dental aligners and intraoral scanners used by dentists and orthodontists. Dentsply Sirona Inc. (NASDAQ:XRAY) is the largest global manufacturer of professional dental products, including medical instruments, dental implants, and orthodontic appliances.

Although Align and Dentsply Sirona serve the same industry, their stocks have gone in different directions so far this year. Align's share price has soared, while Dentsply Sirona stock has plunged. Which of these stocks is the better place for investors to put their money now? 

Dentist crouching down next to young female patient pointing to her smile with both index fingers.

Image source: Getty Images.

The case for Align Technology

We could talk about how Align's revenue continues to skyrocket, routinely setting new all-time highs. We could talk about the fantastic stock performance over the last few years. But the real argument for buying Align Technology stock is the underlying reason behind the revenue and share price increases.

The simple fact is that demand continues to grow rapidly for Align's Invisalign clear aligners and iTero intraoral scanners. And there are several reasons that's the case.

Orthodontic patients like that Invisalign aligners are practically invisible -- a nice change from traditional metal-and-wire braces. Dental professionals like how using the iTero scanners makes creating 3D images of patients' teeth a piece of cake. And those 3D images help streamline the process for patients to use Invisalign. That's a win-win for Align.

Another factor driving demand for Invisalign higher is that Align is reaching more patients across the world. The company recently opened its first Invisalign treatment planning facility in Germany, which boasts the highest population in the European Union. China and other nations with growing middle classes also present an enormous opportunity for Align.

Speaking of enormous opportunities, Invisalign aligners are currently suitable for only 8 million of the 12 million orthodontic cases each year. Align is working on ways for its clear aligners to close this gap -- and expand its addressable market significantly in the process.

Despite its impressive growth, Align still only has a market share of around 13% for its current addressable market (the 8 million annual orthodontic cases). And it only has a little more than 5% of the teen market. That means Align could keep its momentum going for a long time to come.

The case for Dentsply Sirona

Let's get one thing out of the way first: Dentsply Sirona doesn't have the growth story that Align does. However, there could be a kind of tortoise-versus-hare case to be made for Dentsply.

The company might not be increasing its revenue a whole lot, but it does have a nice level of recurring revenue. Consumables made up 48% of total revenue in the second quarter. Even better, Dentsply Sirona reported a year-over-year increase of 7.6% in consumables revenue.

It's true that Dentsply Sirona wrote off more than $1.2 billion in goodwill and intangible impairment in the second quarter. That's not something investors like to see. But it's important to note that one of the key reasons behind this big write-off was the continued disruption resulting from a change in the company's distribution strategy with major U.S. dealers.

These kinds of disruptions can be painful in the short term -- and that's exactly what's happening for Dentsply Sirona. Over the longer term, though, the wrinkles should be ironed out with the new strategy. 

Keeping a long-term perspective is paramount. Dentsply Sirona knows that new technological advances hold the potential to dramatically impact the markets in which it competes. That's why the company is investing in innovation, including partnering with third-party research institutions and dental schools.

In the meantime, Dentsply Sirona offers one thing for investors that Align doesn't: a dividend. Although the company's dividend yield of just under 1% isn't huge, it can add up over time in helping boost Dentsply's total return.

Better buy

If it sounded like making the case for Dentsply Sirona over Align was a struggle for me, it was. In my view, Align Technology is the hands-down winner between these two stocks.

Granted, Align could face more competition than it has in the past. SmileDirectClub, for example, just underwent a round of private funding that valued the company at $3.2 billion. Like Align, SmileDirectClub sells clear aligners. But its product's total cost is much lower than Invisalign's.

I don't think Align has a lot to worry about from potential competition, though. Actually, Align owns 19% of SmileDirectClub. My view is that the market for clear aligners will expand enough for there to be several winners.

In my opinion, Align's big first-mover advantage and commitment to continual innovation will keep the company on top. Align ranks as one of my three biggest stock holdings -- and I don't plan to sell it anytime soon.

Keith Speights owns shares of Align Technology. The Motley Fool owns shares of and recommends Align Technology. The Motley Fool has a disclosure policy.