Chinchilla has consistently wet chin

[GarnetKrow]

Hello, my older (8 or 9 years old) female chinchilla Mimi has recently started having wet fur on her chin, and only her chin.
I tried changing the height of the water bottle to see if that was the issue, but it's still wet.
It won't be wet for about a day, then it'll be wet again.
She's still eating hay and regular food and defecating okay, but I've been supplimenting her with critical care since she's rather thin anyway. She's also been chattering her teeth a little more than usual (I think, but I may be overthinking) but otherwise she's alert and energetic, and comes up for snacks.

I've already made an doctor's appointment for later on in the week to get her checked out. I'm guessing that it's her teeth, but I took her in for a checkup in August and the doctor didn't see any problems so I don't know what to think.
Please let me know if anyone's experienced this, and whether you think it's an emergency issue. Her current appointment is scheduled for this Friday (4 days from now)

Any help is appreciated!

 

[Amethyst]

Having a wet chin normally means drooling. If they just checked her teeth back in August it could just be something minor and fixable like something stuck in her teeth (like hay or a wood sliver), or she has a sore in her mouth. So long as she is still eating and drinking ok she can wait until Friday.

You said she is thin, do you keep a weight record on her? If you don't it's a good idea, often times weight loss is the first sign something is wrong. A small kitchen scale that measures in grams work well. Chins are annoyingly good at hiding illness and injury, so by the time you actually notice something is wrong it means it's gotten to the point that they can't hide it anymore, so you need to watch for little signs.