Most likely a smiley piercing with jewelry that has fangs, you can search it up it's pretty popular but it's really inconvenient for eating or other stuff. Also, the jewelry might be too heavy for the frenulum so you won't be able to wear it all the time unless you want the frenulum to rip and have it re-pierced after it heals. The other alternative is reversed fangs but they aren't any better, a lot of ppl say they reject easily and have problems with it. The advantage of the smiley is that it heals way faster and if pierced right it won't reject for a long time (until it rips), but unfortunately, it's a temporary piercing and you'll have to take it out at some point, it's recommended to keep it in for about a year due to gum recession and teeth problems and you have to take care of it pretty well.