If you got implants, do you have to do touch-ups every 5 years or so?

NO. But it is good to follow up with your plastic surgeon if there are any problems. The FDA asks that MRIs are performed every 3 years or so, but that is not common practice. Usually, implants last a long time, but they may not be permanent. Some patients have their implants their whole life with no problems. Others may have an early problem with a capsule or a rupture.
I usually tell patients that there's a 15% chance of needing another surgery in 10 years. Usually this is to go bigger in size!
If it ain't broke, don't fix it. But best to follow up with your doctor if there are any changes.