Teeth are usually not used during a blowjob, but you never know what "techniques" people are developing these days.
I once new a guy who was really into teeth....he tried to get me to use my teeth. I just could NOT do it. That was too out there for me!
I like some teeth here n there. Some women can't help but use their teeth, when it happens it feels like a really good scratch when it's done right.
Yah I know - I thought it was crazy. I spent too many years making sure I didn't....no way I could have done it even if I wanted to.