what does it for me is an excess of acid food, even though I do clean and floss regularly. orange juice or sharp tasting fruit generally, also the sour jellies and fruit sweets that are available now (and which I love) Cure is to rinse mouth with water regularly, and minimise the acid stuff. My dentist says NOT to brush immediately after food, esp acid food as the acid on the teeth is making the enamel unstable and more easily removed by brushing...he says rinse with water and wait about 30 mins before doing any thing else