my little one has neither.
I pesonally, and its just my opinion. do not like dummys, i think they are ugly. (just my opinion)
but amari doesnt suck her thumb either, she chews her wrist?
iv known pleantly of thumb suckers who havent got dodgy teeth, but then i know pleanty of dummy suckers with fine teeth too....
i wouldnt say thumb sucking is more widely accepted?... i think its down to personal choice.
Iv heard that the sucking reflex usually fads by about 3 months, and quite frankly if you can make it to then a baby shouldnt "need" to suck anything, having said that, my LO still wont sleep unless she is suckled to sleep. so all information you can hear is just an average. and i think you have to do what is right for your baby.
it actually never occured to me to give amari a dummy.