Hi all! A partner and I have been indulging in facesitting with oral recently, and that included some real grinding against my mouth. But while doing that, I was keeping my lips around my teeth so as not to have them touch her pussy and scratch.

That's all well and good, but as she was pressing hard into my mouth, it meant that my teeth really went into the inside of my lip. I tend to get mouth ulcers (canker sores) quite easily as it is, and so this caused me to develop a couple in the next week.

The dilemma is that this is something we both really enjoy, so we absolutely want to do it more. I haven't figured a good way to both:

1. Prevent my teeth from scratching her pussy
2. Protect my lips from my teeth as a result of the force and grinding

If anyone has tips or ideas or alternate positioning that would help alleviate this poor fellow and allow us to enjoy it together more easily, please do say!