DS2 has 1 but has been getting thinner as time goes on, when he first got teeth was a concern as he had a rather wide gap but seems to have improved over time.

Have had no BF issues
Ditto, DD1s was big enough that when her teeth first came through there was a bit of a bigger gap between the front 2 but over time the frenulum and gap have got smaller over time and I don't even notice it now.