This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
2 - 4 weeks
The piercee must have a very pronounced frenulum to be safely pierced;
there must not be any visible blood vessels present. The piercing
should be made in the center of the triangle of the frenulum and not
too close to the base of the tongue where several blood vessels and
glands are present.
Frenulum piercings are prone to rejection. The frenulum is usually
thin and easily torn. Playing with the jewelry frequently can cause or
hasten rejection. Tongue web jewelry accumulates plaque quickly.
Initial jewelry: Captive bead rings in 14 to 12 gauge and 5/16" to
7/16" in diameter. Straight or curved barbells in 14 to 12 gauge and
1/4" to 3/8" in length. A barbell is more appropriate if the wearer
has a tongue piercing with a barbell.
 
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