I always use human hair and I don't seal the ends. They do unravel when the extension hair is new up to where my natural hair ends. It doesn't really bother me, although I'd prefer if they didn't. But since I do have HIHD, it gives me an excuse to occupy my hands while watching TV. I rebraid to the ends systematically: starting maybe with the front ones that I sweep to the side so if I don't get to do all just then, I can style it in a way that it looks like I meant for the others to look different. Or do the ones along the parting so that all top braids look neat and provide a cover for the other unravelled ones. Or just start redoing from back going forward as I find time, and wearing them in a bun till I get them all redone. But most times I just leave them alone to do whatever they please. It seems most pple do. It really doesn't look bad. Here's a style worn with the ends not rebraided.
If you re-use the same human hair for quite some time like I do, you'll find it gets better at retaining the braided pattern and doesn't unravel so much. In the pic below, I'd worn the same human hair for just over a year and the braids were no longer unravellingl:
Perhaps a setting lotion might help? I don't use anything at all on my hair, but I'm guessing a mousse applied to the part that unravels might help, but I really don't know.
