Pitbullfacts.org
There are other breeds that are (per breed) more commonly associated with fatal attacks. What we don’t see is how common each breed is overall.
Big dogs like malamutes and St. Bernards are obviously large all over, including their heads and mouths. The pit bull is only a medium sized dog, except for its head and mouth which are clownishly large. But a bite from one is not funny. This would tend to make the pitbull easier to underestimate. They should be treated with the same respect as malamutes and St. Bernards.
Again I like cats. Their mouths are small. Though I had one almost bite a finger off once. I still have the trick knuckle to show for it.