Even if it said "perfectly treated", I would expect there to still be a chance of further complications, including infection or constant pain.
How many wounds did the dwarf have? How long did it take before each was treated?
The treatment went relatively quick, there were one or two multi-day delays where the dwarf waited in bed for one of the FOUR(FOUR!!!!) medical-only dwarves to get to him. The doctors all had no other labors enabled, they just.... wouldn't stop drinking and eating and sleeping.
The victim in question was a first-month-on-the-job swordsdwarf in training who I threw into a live training room, I believe my mistake was that I threw him in with a goblin general, instead of one of the grunts, but the general was still unarmed and unarmored. If this recruit wasn't made of paper mache I think he would've survived, but instead he was absolutely broken by the goblin's fists. Head torn open, neck torn open, arm torn open, two broken legs and, YOU GUESSED IT: nerve damage. Unhealable, unrealistic nerve damage. I know that's a thing I was just shocked that this dwarf in FULL IRON ARMOR (iron greaves, mail shirt, breastlpate, high boot, gauntlet, and helm) suffered nerve damage! Thinking about it, with that many injuries, I'm guessing soap doesn't beat the odds for infection, and then you just have to hope for survival.
Before you ask, my closest flux layer is all the way down in the first cavern and I hadn't discovered it yet, so that's why I didn't have steel. Would steel have even saved this dwarf, or can fists just..... break your legs through full plate armor?