Why ALGN Q3 earning is on warning?

$Topchoice Medical Co., Inc.(600763)$ 's Q3 earnings missed a lot, so did its stock price dropped. Now the whole dental business is worrying.

Patients spent much on dental problems, which makes is one of the most profitable businesses. Moreover, odontoplasty is out of major medical cares.

Now, there are two major invisible orthodontic leaders in China, one Invisalign $Align Technology(ALGN)$,the other is $ANGELALIGN(06699)$, Among which, ANGELALIGN has been in a high multiples since its IPO.

As for ALGN:

Half of its revenue comes from outside the United States, and Greater China is one of the important sources.

Private dental hospitals in China represent the prosperity of orthodontic industry. Therefore, the example of Tongce, if not a single case, did tell us something——

WE need to be careful on ALGN.

PS: ALGN Q3 earnings tonight.