Someone at the cancer center recommended a water-pic to keep my mouth clean. I used it during RT on a very low pressure setting with about a quarter teaspoon of 50/50 salt/baking-soda added to the water. I still used it daily.

I had PEG tube problems and got mine removed early. I don't recommend this because I wasn't able to holding my weight. My appetite was very poor and, after a bite or two, food tasted bad. I was living on body fat and grape juice and my RO threatened to put a PEG back in!

Try if you can to get your PEG fixed and hold on to it until you can easily hold your weight by eating normally. Without a lot of effort, this can take a few months.