A 48 year old woman presents for a routine check-up. Since you are mindful of your Foundations of Patient Care (FPC) training to ask about sexuality, you ask her if she has any questions or concerns about her sexual functioning. She mentions that she gets some vaginal dryness, but noticing your anxiety, declines a pelvic exam. As you ask about other changes in her health, she says that she feels like she has "meth mouth", though she claims she stopped using that stuff over a decade ago. When you look at her oral cavity, you notice pretty advanced tooth decay. "Oh and one more thing," she says, "I feel like I get sand in my eyes a lot."
A lip biopsy shows this:
1. What is the cause of her tooth decay? What's the medical term for it?
2. What's shown on the biopsy?
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