I Have A "butt" Rash....light Pink And Red. In My

I have a "butt" rash....light pink and red. In my "crack" and spreading around the area. Is now creeping up to my lower back. All very itchy. Also noticed tonight that my lower legs are itchy. (I am under a dentist care who is making new uppers and llowers...am due for a new fitting this week). Any thing to worry about or look for?
Bob

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