Guinea pig oral issue

Question
QUESTION: We have a 3.5 year old male guinea pig who is having something wrong orally. When we woke up this morning, we noticed he must have drooled over night and there is a thick white substance that stuck his lower lip to his chin hair, causing his lower lip to be constantly protruded (unless he chatters his teeth). He is acting normally--eating, drinking, not lethargic, and purring, as far as we can tell. His front teeth look the same I think...perhaps his lower front teeth are slightly tilting behind the uppers. We have a vet appointment for him in about 48 hours. What is this all about? Should we be extremely concerned?

ANSWER: Hello Katie and Rob!
Well, I must say that this is defiantly one of those questions for me! I looked through all my sites and all my books and looked for 45 mins before deciding I have no idea what this might be. Surprisingly not even anything close!
I'm sorry, I tried my best but still cannot find anything. The best advice I can give you is to find an exotic pet vet and see if you can get in sooner.
Give your piggy a hug for me!

---------- FOLLOW-UP ----------

QUESTION: Thanks for your response. I noticed tonight that now his lip is normal (I started to dig at whatever it was stuck to it). However, I am still noticing that he has started to extend his neck occasionally when chewing/swallowing. Does this sound more like malocclusion now? That was my first thought with the drool--but his behavior is normal. I can't get a good look at his teeth.

Answer
Hello again!
I am glad that he is feeling normal!
About the possible diagnosis you came up with. I will give you a link to my favorite guinea pig health sites. It lead directly to the page about Malocclusion and Elongated Roots.

http://www.guinealynx.info/malocclusion.html

I suggest reading and looking into this because nobody knows a GP more than its owner!