Epp I wrote a massive in depth reply and the laptop shut down!
The basis of it was that I experienced an abscess with an elderly rabbit called Jake with an abscess at the bottom of his ear. They commonly spread to the bone and even when treatment destroys the abscess, when they infection has reached the bone they frequently re-occur. In young bunnies though it's often possible to just treat them as and when they appear.
I found flushing the abscess was the most effective method, very intrusive and a bit distressing for me but I had a very strong bond with my Jake and he trusted me.
As you probably know, rabbit produce a completely different kind of pus from a cat or dog. Very thick, they're body's natural defense system fights the infection by creating this thick wall around it. This unfortunately causes the abscess. The catch 22 is that some, depending on where they are, cause the rabbit no bother and some owners choose not to treat them, this creates a time bomb as the contents will eventually become toxic. Opening the wound and hitting the heart of it hard with antibiotics is the best option.
The problem that I had treating Jake was that his age (7) meant anesthetic was risky and the medication upset the delicate digestive system all bunnies have.
The first treatment however was a great success and had he been younger I would have happily continued to treat him as and when the abscesses occurred. Apparently this is anything from 6-18 months.
I choose to flush the abscess daily and baitryl was inserted. Within 6 weeks it was completely gone. It re-occurred 6 months later and purely due to his age he didn't have the fight left in him so I choose not to treat him again.
I found the best help came from an 'exotic vet' also. I always assumed this would involve reptiles, birds etc but apparently exotic vets have a great interest in bunnies as they require a great deal of knowledge to treat. Hitting the abscess fast and hard is usually the best method and (as I said before) although it's invasive it's the most effective treatment.
I don't know the age of your bun but if he/she is you and otherwise fit I would personally recommend this treatment over the beads.
I hope this helps in some way