Razor sharp, needle like teeth. A seeming never ending desire to chomp down on the most delicate of human fleshy parts.
No, I'm not talking about piranhas, I'm talking about puppies!
One of the first dog training protocol you will want to initiate when you get a new puppy is to teach him to inhibit (puppy bite inhibition) the force of his play-bites. It is not necessary to reprimand the pup, and certainly physical punishments are not called for. But it is essential to let your puppy know that bites can hurt.
A simple "Ouch!" is usually sufficient. When the puppy backs off, take a short time-out to "lick your wounds," instruct your pup to come, sit, and lie down to apologize and make up. Then resume playing.
If your puppy does not respond to your yelp by easing up or backing off, an effective technique is to call the puppy a "Bully!" and then leave the room and shut the door. Allow the pup a minute or two time-out to reflect on the association between his painful bite and the immediate departure of his favorite human chew-toy. Then return to make up. It is important to show that you still love your puppy, only that his painful bites are objectionable. Have your pup come and sit and then resume playing once more.
It is much better for you to walk away from the pup than to physically restrain him or remove him to his confinement area at a time when he is biting too hard. So make a habit of playing with your puppy in his long-term confinement area. This technique is remarkably effective with lead-headed dogs, since it is precisely the way puppies learn to inhibit the force of their bites when playing with each other.
If one puppy bites another too hard, the dog who gets bitten yelps and playing is postponed while he licks his wounds. The biter soon learns that hard bites interrupt an otherwise enjoyable play session. He learns to bite more softly once play resumes.
The next step is to eliminate bite pressure entirely, even though the "bites" no longer hurt. While your puppy is chewing his human chew-toy, wait for a bite that is harder than the rest and respond as if it really hurt, even though it didn't: "Ouch – Gennntly! That really hurt me, you bully!" Your puppy begins to think, "Good heavens! These humans are soooooo sensitive. I'll have to be really careful when mouthing their delicate skin." And that's precisely what you want your pup to think: that he needs to be extremely careful and gentle when playing with people.
Your pup should learn not to hurt people well before he is three months old. Ideally, by the time he is four and a half months old (before he develops strong jaws and adult canine teeth) he should no longer be exerting any pressure when mouthing.
Summary:
Teaching bite inhibition to puppies is actually a really important step as it is the ideal time in their learning cycle to initiate a response that shows them that they are capable if inflicting unwanted pain on species other than their own. They must learn early that human flesh is gentle and sinking their little teeth in to people's skin is highly undesirable.