I hear of gu8ys wearing butt plugs all day or night....will this cause damage to the sphincter where you could eventually lose control of your bowels? Would the anus stay more openafter removing the plug?
So the easy answer to both these questions is no. But the more complicated answer is no, but only if you're smart about plug usage.
If you're using a plug properly and safely with plenty of lube and not going bigger than you're ready for too fast, you will not damage your sphincter. But even if you do the damage will be something like a fissure or a hemorrhoid, neither of which will cause you to lose control of your bowels, but will make movements hurt. Long term usage can have your sphincter open after you remove it, but it's never happened to me and I've been plugged for almost half a day before. And even if it did, your sphincter goes back pretty quickly. You can even help it by working your way down to a smaller plug or single finger.
Your sphincter actually doesn't control your bowels, that's the job of the sigmoid colon, which is farther up than most plugs reach. That being said, if you use a large plug made out of a cheap, hard plastic, you can do damage to some important nerves in your lower back that will cause your sigmoid to be less effective. So for long term plugging, especially starting out, stick to smaller and softer plugs. Silicone is the best IMHO and there's a few good sellers for long term wear like Square Peg (Egg Plug) and Topped Toys. Topped Toys also has some blogs with helpful guides to long term anal play.
That was long winded but I hope it helped!