After Morrowinds main quest we kill Dagoth Ur and house Dagoth Ur is destroyed. But i was wondering if there was potential for remnants to survive or return?

For instance if we ever returned to Morrowind near the time of Skyrim, would we find any remnants of House Dagoth outside of a history book?

Outside a handful of a handful of pustule schizoids consumed by corprus, we shouldn't find any remnants. Unfortunately, something tells me that's not the case. Consult Dragonborn or those who've played it. I can only tell you what Morrowind lore would lead me to believe. Remember the Nerevarine was supposed to have hunted the Ash Vampires to the last, before ever setting his sights on Dagoth Ur. (No, we don't have to, but those were the canonical planbook.) That means any surviving kin would only be of the ascended or ghoul variety. Make of that what you will.

No reason for it to be impossible, no one can guarantee that one or few ash vampires didn't manage to flee unnoticed.

After the main quest, the bodies of the Ash Vampires (even the ones the player did not kill if they chose not to) are found dead in their citadels. So while some lower members may have fled, the Ash Vampires are gone (at least in the same sense that Ur is gone).

Aaah, my bad, I totally forgot that happens.