Clinical diagnosis, based on history and physical exam
Consider X-ray
If concern for retained foreign body (e.g. tooth)
To rule out fracture (adult dogs may exert >200 lbs force bite)
Consider Ultrasound
If concern for abscess or foreign body
CT Angio if concern for vascular injury
Wounds overlying a joint should be examined through complete range of motion to assess for tendon injury
If concern for retained foreign body (e.g. tooth)
To rule out fracture (adult dogs may exert >200 lbs force bite)
If concern for abscess or foreign body
Mammalian bites
Hymenoptera stings 
Spider bites
Snake bites
Closed fist infection 
Lizard bites
Dog bite
Octopus bite