Looking at LAYA FLEX 375 CHOICE it seems that a dental x-ray is covered under "routine dental".
However, I assume that the x-ray is subject to the limit of indemnity for that benefit which seems to be €60 per year.
See page 6 of the rules - link - https://www.layahealthcare.ie/media/site/pdfs/genericrules.pdf
I don't imagine that dental x-ray comes within "radiology" cover.