I googled "How to stop my dog from biting?" and found some interesting articles. I thought these might be helpful...
Lack of Socialization Causes Biting
A major cause of biting is lack of socialization. Lack of socialization often results in fearful or aggressive behavior. The two major reactions a dog has to something it is afraid of are to avoid it or to act aggressive in an attempt to make it go away. This is the most common cause of children being bitten. Dogs that are not socialized with children often end up biting them.
The optimum time to socialize is before the dog reaches 4 months. With large breed dogs, 4 months may be too late, simply because at this age the puppy may already be too large for most mothers of young children to feel comfortable around. For most owners, the larger the dog is, the more difficult it is to control, especially around children. If there is anything you do not want your dog to be afraid of or aggressive towards, you must begin to socialize your puppy with them before 4 months of age.
Trust and Respect Inhibits Biting
There are many other reasons your dog will bite and you will have to take an active role in teaching them. However, before you can teach your dog anything, there are two prerequisites that are essential. They are trust and respect. If your dog doesn't trust you, there is no reason why he should respect you. If your dog does not respect you, your relationship will be like two 5 year olds bossing each other around. If your dog does not trust and respect you, then when you attempt to teach your dog something, he will regard you as if he were thinking, "Who do you think you are to tell me what to do?"
Use of Reprimands and Biting Never hit, kick or slap your dog. This is the quickest way to erode the dog's trust in you. Yes, he will still love you. Even abused dogs love their owners. A unique characteristic of dogs is their unconditional love. You don't have to do anything to acquire your dog's love. But you must do a lot to gain your dog's trust and respect. Another area where we destroy our dog's trust in us is when we scold or punish them for housesoiling mistakes and accidents. When housetraining your puppy, there is never an appropriate time to punish or reprimand. If you catch your dog in the act, just head for the towels and cleaner. You have no right to scold him, because if he is going in the wrong place, it is your fault, not his. If you find an accident after the fact, just clean it up.
Summary Tips on Biting
1. Reprimand alone will never stop biting.
2. If no respect exists, the biting will get worse. If you act like a littermate, the dog will treat you as one.
3. If trust is not there, the dog may eventually bite out of fear or lack of confidence.
4. Inconsistency sabotages training. If you let the dog bite some of the time, then biting will never be completely eliminated.
5. Don't forget follow up. The dog must understand that it is the biting that you don't like, not the dog itself. Make up afterwards, but on your terms, not the dog's.