Flush a mild disinfectant into the wound under light pressure. You can use an eyedropper, turkey baster, bulb syringe, or a syringe.
You can use a disinfectant such as 0.001$-1% povidone-iodine (the more dilute solutions are less damaging to healthy tissue), 0.05% chlorhexidine, and 0.125%-0.5% sodium hypochlorite (one fourth to full strenght Dakin's solution), which can be made by diluting household bleach 1:10 to 1:40 with water.
You could also use hydrogen peroxide and the concentrate should only be about 3%.
Or you could use a Boric Acid solution. It comes in powdered form, and you can mix it up as per the directions on the bottle with distilled water.
Do not apply any oil-based antibiotic ointments or those containing the local anesthetic benzocaine. This may interfere with healing.
If possible, antibiotics should be administered by a veterinarian within 24 hours of injury
Examine daily for infection. If the wound becomes infected take your dog to your veterinarian.