An animal dentist who worked on one of my rabbit's teeth for many years did tell me that teeth can, and many times do grow back after being excised. If there is even a miniscule piece of the tooth remaining it is capable of returning. As far as I know this is not something that the dentist/vet has any control over. My Holland lop had molars grow back after being excised.
Probably should get full mouth x-rays on this rabbit. The infection could be infected tooth roots, gum disease, an infected tooth or something not related to the teeth ( but probably is.)
Best to have a very rabbit knowledgeable dentist /vet review the x-rays and give you an opinion Some teeth may have to come out due to infection and you may need to have some of them filed to ensure the rabbit is pain free and able to eat. Probably need antibiotics also for the infection.
Trimming teeth is really not recommended as it places pressure on the pulp and often can cause the root to die thus creating another problem. Some vets drill with a dremel but this also carries risks and filing is the optimal approach (although total excision is also an option)
Teeth problems are a life -long issue for a rabbit and if you are going to commit to it it is best to attempt to get the most knowledgeable folks that you can involved. Seems like having another total excision may be another option down the road, however, best to find out exactly what you are dealing with before going that route.
