They are an amazing breed of dog that are really gentle. The most important thing to look into when selecting a dog breed is the history of the breed. Was it breed for fighting? Guarding? Attacking? Or was it breed to be gentle? Labs were bred for to be gentle with their mouths, because they were trained to go and retrieve ducks and other game that a hunter shot down, and not play with it or bruise or puncture it by biting it too hard. Other breeds were meant to be attack or guard dogs, and they can get aggressive. Also, get a book on dog communication; How to Speak Dog is a good one. One of the reason, I think, small children get bitten by dogs more often than bigger people is that kids are down on their level, and they can stare the dog right in the face. To a dog, that’s a threatening pose, and if it’s a breed that is meant for attacking and defending, it might do just that, and attack. Of course, I know that not ALL dogs of particular breeds would attack, and not ALL labs are completely gentle, but the vast majority of the time, Lab are very docile, and other breeds get aggressive.
On a personal note, my family has an 8yo yellow Lab named Toby. He is the sweetest, most gentle dog I have ever met! When we play with him, with his toys, and our hand accidentally ends up in his mouth, as soon as he notices, he lets go. He has never bitten anyone, not once. Even when us kids did something he didn’t like, like hold onto one of his paws, he would just kind of nibble at our hand, and make distressed noises. I <3 Toby!