I need a tooth fairy

I’m very stressed because I don’t know how to address this. It’s very awkward for me.

My bf has a missing front tooth that he has yet to get fixed even though he said he would. Now he’s starting to get tarter build up. This is a turn off and it’s embarrassing. I barely want to kiss him anymore. I love him and I would hate for something this small to stand in the way of the good person he is, but this is bothersome.

How can I gently encourage him to take care of these issues and be sure it gets taken care of ?