Deep wounds
Bites that are very deep should be put in the capable hands of your vet. I had a chat with my own vet and asked him what sort of process your guinea pig may go through. The wound may need stitches right away, or your vet may choose to leave the wound open for a few days while antibiotics are given to kill any bacteria first before applying stitches. Your vet will do what they feel is best. Keep your pet on clean bedding during the healing process and keep them away from companions until healed.