How long, realistically, before I will need dentures?

I have had a lot of dental work done in the last couple of months: 11 fillings, 4 root cs, and 2 wisdom teeth removed( I only had 2). All of the root cs were crowned. So now that I have had all this work, I find myself wondering how much of a lost cause this has all been. How long can I realistically expect my teeth to last? I have become very neurotic about my dental care lately and am brushing almost immediately after I stick anything in my mouth, and a minimum of 3 times per day. Also I floss very well 1 time per day and 2 other times just quickly with the handheld version and am using a florid rinse. Is it worth it? or will I be going in 5 years to have everything taken out and receiving false ones?