Can you do a q-tip dipped in warm water? That typically does pretty well to take off any readily-removable crusts.

Teeth grinding is a sign of pain, but in younger rabbits it can be a sign of content… very confusing. Does he seem generally content, or does he seem uncomfortable?

If the crust area gets bigger, I would visit your exotic/rabbit vet. It could be a topical infection, such as ringworm.

If it doesn’t come off with a bit of warm water, then it’s not dried milk and probably needs a vet.

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I would have it assessed by a vet if the water hasn’t helped remove it. Best case scenario, it’s really gunked on food or something, in which case an exotic vet may be able to safely clean it off at the visit. Worst case scenario, it’s a sign of a medical condition, in which case the exotic vet will help with treatment and next steps.

That all aside, I’m glad he seems to be doing well though! Topical maladies may not make rabbits too upset, but it’s good to have them treated before they get out of hand and become a source of suffering. Wick has had ringworm for like, 5 months now honestly and while me treating it bothers him x10 more than it on its own, without the treatment, he’d lose all his fur eventually…. and become a rampant source of ringworm.

He definitely needs a vet. It could be an abscess, and an abscess in that spot can be cause by tooth problems which can quickly turn into pain then stasis. Its great hes doing better now, but its better to be safe than sorry

GI Stasis is when a rabbit stops eating and has very little or no poop. It can make a rabbit become gravely ill very quickly. That is why at the top of the page there is the line “Bunny 911: If your rabbit hasn’t eaten or pooped in 12-24 hours, call a vet immediately!”  

Is he eating pellets and hay now? They’ll often start sampling solid food around 3wks old and eating a good amount by 5 wks old. Is he still being given goats milk?