Yes that is healing for a dog, but in general activity surely a dog licking excrement in the park then licking your face is not hygenic! You can get worms from them.
I vaguely recall storyline in some book in which someone trapped in the wilderness with injuries let a pet dog or pet wolf lick their wounds and it helped heal (similar to what Max said). Another thing I heard is using maggots to help heal a wound, as the maggots eat the infected bits of flesh.
Should You Let Your Dog Lick You
Do you like it when your dog licks your face or hands? Some pet owners find this disgusting. Others consider it a loving gesture that makes you even closer to them. If you are like the latter, then you may want to think again. It may seem affectionate and fun but, your dog's lick could give you more than you asked for.
To get an idea of why you may not want your dog licking you, all you have to do is think of the places a dog's tongue frequently visits. Most dogs spend a lot of time licking garbage, dirt, sticks and even their private areas and feces on the lawn. It's obvious that remnants of these things could still be on their tongue while they are licking you. Even if the garbage and feces are not in the dog's mouth, the bacteria from them probably is. This means that letting your dog lick your face may not be the cleanliest decision.
There are many health risks associated with letting your dog lick you. One of the biggest is roundworms. Roundworms are an intestinal parasite commonly found in puppies and can be passed to you through licking. If you get your pet tested regularly and give it de-worming medication every month, the risk is slim to none. Either way it's something to consider if you are going to let your dog lick you anytime they please. Some serious medical conditions can be caused by roundworms. Symptoms are cough, fever and headache.
Other illnesses and diseases can be transmitted in addition to roundworms. These include
Leptospirosis, Salmonella, and E. coli. These can all be passed through the saliva. Also, strep throat has been linked to dogs licking their owner's faces. Far less likely but, still something to think about is that Rabies is also transmitted through saliva, but if you keep your dog vaccinated this should not be an issue.
Some dog owners will say that a dog's saliva actually contains an enzyme that promotes healing and will encourage their dog to lick their cuts or wounds. This fact is true, but the enzyme only works on the wounds of dogs and does not help humans at all. Therefore, you should not encourage your dog to lick open wounds or cuts on you as this will only increase your chance of infection.
In closing, while your pet passing on and illness or parasite to you is unlikely if you keep them properly vaccinated and tested, it may still be a good idea to discourage licking in order to reduce the chances even more.
http://www.friendsofthedog.co.za/1/p...your-face.html