Hi XXXXXXXXXXXXXX,
Since he was bitten by a larger dog, even though there is no bleeding ,damage to tissue and muscle underneath that can't be seen by you may have occurred. Also a dogs mouth is full of bacteria so an infection can set in fairly quickly. I would keep the wound clean using providone iodine (drug store) and apply a triple antibiotic ointment to the wound. Watch closely for infection, or any changes in behavior as this is a good indication something is wrong. Sometime keeping the wound clean and free of infection is enough, so monitor the area daily, but see a vet if you notice anything different in the dog.
Here is more on bite wounds. http://www.petplace.com/dogs/bite-wounds-in-dogs/page1.aspx
dog training consultant
24 years training & behavior,pet first aide, Therapy dog eval., PA Animal Response Team