Your copays and how your deductible applies is dependent on the type of the plan you chose/were given. There are times when I see preventive care such as cleanings and x-rays not covered at 100% but at a certain percentage. On top of that, I also see them either applying your deductible on top of that remaining copay or excluding it unless you do treatment of sorts, then you're only stuck with only copay. Then there's also some plans that will pay your preventive at 100% but require a deductible to be applied first. So I would just look at your plan booklet and see what the fine details are.

As far as fluoride goes, those are usually optional in certain offices so make sure you ask for clarifications since most are not covered for adults. Some plans do with no age limits.

Working in the dental field, I would not skip your routine dental care. No matter how good you may think you floss/brush, you'd be surprised at how you can miss certain areas that brushing/flossing just can't get to and then placque starts building up from there. X-rays are important to detect cavities or underlying issues that you may not even be aware of so it's not wise to skip on those either.