One of our observant rescue volunteers noticed that Popo's bottom teeth were overgrowing into his top gums. This was an urgent medical situation.
The first picture is from before the surgery. As you can see, one of his bottom incisors is pointed and was causing him huge amounts of discomfort and limiting his ability to eat. His ears were bright red instead of their normal pink. The vet put Popo under anesthesia and trimmed both sets of teeth to even them up and within a day the redness in his pink ears had gone down. His teeth were evened out so he could eat solid foods again.
The moral of the story is simple: Check your piggies' teeth on a regular basis to catch any issues like this. Not only are teeth problems expensive, but they can be fatal if your piggy stops eating or gets an infection.