Like every other piercing, there is a small risk of infection. … If you wear a captive bead ring in your smiley piercing, you might end up with gum recession and tooth damage. The ball will rub repeatedly against your teeth on a daily basis and you may end up damaging the enamel on your teeth.
Beside above, how bad does a smiley piercing hurt?
Pain is possible with all piercings. Generally speaking, the fleshier the area, the less the piercing will hurt. Your frenulum has to be thick enough to support the jewelry, but the piece of tissue is still rather small. Because of this, the piercing may hurt a bit more than a lip or earlobe piercing.
Then, what gauge should a smiley piercing be?
18 gauge