Yeah, meth will rot your teeth out. That isn't propaganda whatsoever but it is possible to take some countermeasures. It is caused by a combination of dry mouth (everyone gets this side effect) and being neglectful of your health and dental hygiene while on binges. Not to mention the corrosive chemicals involved.
Seems simple to fix, carry around a bottle of water and drink plenty, make sure you brush your teeth daily and again after each use, monitor nutrition and sleep at night.
BUT the high that meth will give you tends to make you spacey, hyper, unconcerned about healthy habits, easily distracted, forgetful, etc. You may plan on doing these healthy things on your binge, but once you're high as fuck you won't give a shit anymore, lol. Plus you simply forget how dehydrated you are.