Hi GPL
Firstly - Well done on your observation - you appear to have picked up early warning signs of possible dental issues - most probably the molars are overgrowing and starting to trap the tongue in view of the issues with messy water drinking and selective eating of dried food....and the weight loss could be associated with that. Yes - it can be really slow and subtle in its presentation when you have an older piggie,
Also I'm pleased to see you are being cautious in your approach in order to ensure Sampson gets the best treatment.
To hopefully answer your questions/give more info:
1) Before you see the vets tomorrow - there is not much you can do to see his teeth yourself. Don't worry too much about the incisors. The best thing you can do is to start topping up his food intake to keep his guts moving by syringe feeding mushed pellets (actually given what you describe I'd hope Sampson would be happy to eat softened nuggets in his bowl or slush off a spoon rather than resort to "the dreaded syringe" !)
2) How can you prepare for tomorrow?
When vets try to look at a piggie's teeth - they usually stick the "otoscope thingy" in the mouth (the shiny metal cone-shaped thing with a light that is also used for ears) only to discover (surprise surprise) that they can;t see the back molars because the piggie has food in it's mouth. Piggies are herbivores, their mouths are completely different to ours and cats/dogs etc. They have a massive cavity (called the diastema) between the front teeth (incisors) and the back teeth (premolars and molars) in which food accumulates and hence, unless a vet is willing to wash the food out of this area first and has the proper equipment - they don;t have a hope in hell of seeing the back teeth properly. Very few vets are able to do a proper conscious dental exam because they do not know how (and if they're like my own vets, seem unwilling to learn).
Let's be clear - a dental [*]exam[/*] is different from then going on to do dental [*]treatment[/*] to rectify a problem found- but because of the above, most vets need to perform a GA to perform the exam first and then go on to treat at the same time if needs be.
So if your vet only uses the otoscope thingy , you can improve their chances of seeing the molars by helping to clear the food in the diastema as follows:
At least 90mins before the vets visit, withdraw all food (including hay) and feed instead cucumber WITHOUT the skin. This will help clear the piggies mouth of fibrous food so the molars can be seen
I have done this with some success in the past - however I do now prefer to get a full exam done by one of the few vets i know who does this successfully without resorting to GA no matter how much food is in the mouth i.e. Simon Maddock at Cat and Rabbit Clinic Northampton (see Minty and Gary's post - and I also support what they say about not letting treatment take place unless you are sure as often it causes more harm than good)
3) What happens after the initial exam?
Your next step will be entirely dependent upon what your vet says, how confident you feel with them and the examination they conducted ..and their ability to anaesthetise/treat dental problems.....and whether you can make a long journey if you feel unhappy with or lack confidence in their advice/findings.
Just to give you a reference point: Depending upon Simon;s findings he will then treat there and then (without GA) or we will then discuss the next stage if a GA is necessary. It is a 4-5hr round trip for me - but building on my many years experience of different vets etc I think it;s worth it. If you book in and say its guinea pig with a possible dental issue - you get a half hour appointment booked for you and it's half the price of a standard consult with my normal vets (who would tell me they can;t see anything and it will then cost me upwards of £150 for a GA to deterimine/treat a possible dental issue)
As said before - lots of vets mistakenly assume a piggie's incisors are too long/not shaped properly and trim them unnecessarily, causing problems (even death). Piggies incisors are NOT the same as rabbits and should not be compared with them as a basis/justification for deciding treatment. We have also had cases of vets missing molar spurs - again causing a lot of problems, pain and heartache for both guinea pigs and owers. I strongly advise you, (if you can and are able), to seek a second opinion before agreeing to dental treatment unless you feel totally confident in your vets.
Good luck tomorrow - hope the info above helps you in deciding what to do/whether to put your trust in your vets as I can completely sympathise - I've spent years of heartache (and expense) getting to where I am now in terms of when I use my usual exotics-specialist vets (and what for) and when I go see another vet (Simon) because of their expertise in a particular issue - i.e. dental!
x