i have been following this thread for a while now but i just want to add this one thing and thats it.
everyone has pretty much turned on the pit saying it is such a terrible dog and it was definately him. but you cant be so sure so lets not doom a dog which has seemed to be a great dog til this incident. besides knowing a little bit about pits and having a boxers my whole life until i moved out of my parents i know this.
boxers tend to pick on or beat around smaller more vulnrable (sp) dogs but never intend to hurt the dog. the puppy is still developing so its bones, muscles, reflexes, depth perception etc are not all there yet and this prolly led to the severity of the incident. if it was the pit there wouldnt have been a chance to take the puppy to the doctor if it was actually "intending" to hurt or do worse to the puppy, the pits jaws would have locked and they do not release until the dog is dead, esspecially for a puppy it would have been real quick. it is virtually impossible to get the dogs to release unless a person could go for sensitive areas such as eyes or something. as it does not sound like you walked in during the middle of the incident i would say it was definately not the pit and either way i believe both the dogs didnt intend to hurt the puppy.
so before you doom dogs know a little bit about and have experience with the breeds. good luck with your doggies and do not be mad or hold a grudge against the dogs, im sure it was a freek thing and prolly scared your dogs more than anything else.