What happened

After falling more than 23% in July, Align Technology (NASDAQ:ALGN) slipped another 12.4% in August, according to data provided by S&P Global Market Intelligence. Investors are clearly still worried about decelerating growth at the orthodontic-device specialist.

So what

On its second-quarter earnings call, Align Technology guided for third-quarter revenue growth of 16% to 19% compared to the year-ago quarter. That's a substantial slowdown from the 22.5% growth in the second quarter, which was a deceleration from the 25.6% year-over-year growth seen in the first quarter.

Management blamed slowdowns in China and in its young-adult category in North America for the moderating growth.

Smiling woman displays her orthodontic device.

Image source: Getty Images.

At the end of July, Align Technology announced an accelerated stock repurchase plan to buy back $200 million worth of stock over three months. At the same time, president and CEO Joe Hogan committed to personally buying $1 million worth of shares.

Clearly, neither initiative has given investors much confidence.

Now what

This decline could certainly be a buying opportunity, but keep in mind that much of the decline was due to Align Technology being priced for growth. Even after the decline, shares are only down about 15% year to date. With so many healthcare stocks to invest in, it's hard to get excited about one that might be having trouble putting its foot back on the gas.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.