Puppies chew – it is what they do! Partly because they are teething, partly because it’s enjoyable, and partly because they don’t know what is valuable or dangerous and what isn’t. This is part of puppy development – plus chewing is a rewarding thing for dogs to do.
Make sure you do not leave anything within reach of your puppy that isn’t safe for him to gnaw on. Pick up shoes, plants, clothes, electric cables, and other items of value, so there is nothing to tempt him!
Ensure he has things of his own to chew (see the Oscar range of chews) that are more interesting than anything else in the house he might try his teeth on. A puppy needs an opportunity to chew and gnaw – so you need to provide this for him.
There are several types of chew toys available. Provided they are safe and washable, they can be filled with food to give your puppy a chance to do all the chewing he needs safely. Start off by making it easy for him to get the food out, then after he has got the hang of it, you can make it far more fiendish.
If you catch your puppy chewing anything he shouldn’t be, quietly move him away and give him his own, far more interesting, chew toy to distract him.
Up until now all your puppy’s play time with his littermates and his mother have been toothy games! It is natural that he will think that this is how to play with his new human family too.
Teaching him not to play bite needs all the family to do exactly the same thing – and make sure there is no one in the household encouraging the puppy to do this.
If the puppy bites (not just mouthing but actually closes his teeth), squeak as if it hurt and stop playing for 10-20 seconds. This is what his mother or his littermates would do if he bit a little too hard. Repeat any time he bites until he learns that if he wants to play and interact with you he must keep his teeth to himself.
If doing this makes your puppy even more excited and mouthy, you may need to leave the room for 10 seconds.
When he stops biting however you can reward him by carrying on with the game or your interaction.
If, however he is biting to stop you handling him, take advice from a professional.