I went to a dentist to fix my front broken tooth and he did a filling and then it came off two weeks later. Then I went to another dentist who did tooth bonding and he put like a pin, could it be? or a little piece of metal to complete the restoration. So do you think this will work? My tooth looks okay, but it feels a little thick on the back.
—Irina in Ontario
Irina, The pin is an OLD technique that dentists who are familiar with bonding technology don’t use any more. With modern bonding technology, pins aren’t really necessary. If it’s bonded well, you don’t need any pins.
But if the filling isn’t bonded really well, the pin will help it hold in. The pin is screwed into the tooth, and it has a small round head. The filling fills in around the head, and this helps hold the filling in.
They’re very tiny—a fraction of a millimeter in diameter and maybe a couple of millimeters long.
There are two problems with pins. While they hold fillings well, they tend to propagate cracks in the tooth around the hole where they’re screwed in. Also, in white fillings, depending on where they’re placed, they can show through the filling, appearing like a little gray spot in the filling. Sometimes they may not show through at first but later will corrode and then darken the filling.
For dentists who are still doing amalgam fillings, pins do help in some situations, because amalgam doesn’t bond to the tooth.
—Dr. David Hall
Some pins can provoke a metal allergy.