This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
Eyebrow
Eyebrow piercing retainers are short lengths of wire with a small hook
at one end which is worn over the top entrance of the
piercing. Eyebrow retainers are not secure and should not be worn in
new piercings. Niobium and titanium retainers may be anodized to to
colors close to skin tones to appear less conspicuous than steel
retainers.
Nostril and Labret
Niobium and titanium nostril screws and labret ends may be anodized to
colors close to skin tones. Small domes and flat discs are less
conspicuous than balls.
Nostril screws can be disguised by coating the ball with skin tone
colored nail polish. Remove the jewelry before applying the nail
polish and allow it to dry thoroughly before wearing. This method
should only be used for healed piercings.
A few manufacturers make acrylic labret piercing retainers which are
similar to labret studs but with a colorless rubber o-ring on the
front to secure the stud.
Septum
Septum retainers are U-shaped pieces of metal, either rounded or
squared-off, usually between 5/16" and 3/8" wide and approximately
3/8" long. The spread of the shanks should be adjusted so that the
retainer may be comfortably flipped up into the nose but snug enough
to prevent losing the retainer. Wire in gauges larger than 10 is more
difficult to shape into a small U shape. Some manufacturers make large
gauge retainers with thinner shanks so that the retainer can be
accurately shaped and adjusted. For piercings larger than 8ga, plugs
or eyelets may be more comfortable ormore readily available than
retainers.
Tongue
Tongue jewelry is most visible when the wearer is laughing and
yawning. Colored titanium, niobium, plastic or acrylic balls are less
conspicuous than steel balls. Unfortunately titanium and niobium
jewelry will fade over time. Plastic or acrylic balls which have been
colored with vegetable dye will also fade over time. Plastic and
acrylic cannot be autoclave sterilized and hence cannot be worn in a
new piercing. Plastic balls can break if bitten hard enough.
A few manufacturers make acrylic tongue piercing retainers which are
similar to labret studs but with a colorless rubber o-ring on the top
to secure the stud. Retainers cannot be worn in new piercings because
acrylic cannot be autoclave sterilized; additiionally, swelling can
force off the o-ring.
"No-C-Um" barbells are pink dental acrylic saucer-shaped balls
internally threaded into a metal bar post.
 
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