How to Prep Properly for Pediatric Crown Placement
A successful restoration starts with a good foundation. Although the amount of decay or other damage makes each tooth unique, one should follow best practices when prepping crowns for pediatric patients.
Start with a clean field
“I always prep all the fillings first,” says Jason Bresler, DMD, of Doc Bresler’s Cavity Busters, a pediatric dental practice with eight locations in the greater Philadelphia area. He is also an assistant professor of pediatric dentistry at Temple’s Kornberg School. In 2018, Incisal Edge Magazine named him one of the top 40 dentists under the age of 40 in the United States.
Prepping the fillings before prepping the crowns makes it easier to get an unobstructed view of all teeth throughout the procedure, as crown prep can generate some blood.
Prepping teeth for pediatric crowns is a simple process. To start, reduce the occlusal surface by 1.5 mm to 2 mm. Next, using a #700 bur, make interproximal cuts all around the tooth. A #700 bur is similar to a #169 bur, but it has a cross-cut fissures, making it easier to cut interproximal slices.
Don’t overlook the lingual
The goal is to create a shape that matches the inside of the crown, so the crown seats easily. Make sure to remove enough enamel from the lingual/palatal side of the tooth. It’s easy to see when you have removed enough from the facial/buccal side when you’re prepping a tooth, but it is more difficult to visualize the lingual/palatal side. When a crown does not seat easily, it is often due to failure to remove sufficient enamel from the lingual/palatal side.
“That seems to be where most people get hung up—they don’t take enough off the lingual, and then the crowns don’t seat all the way,” says Joshua Bresler, DMD, another key member of the Doc Bresler’s Cavity Busters team. Dr. Josh is also an assistant professor of pediatric dentistry at both Temple University Kornberg School of Dentistry and the University of Pennsylvania School of Dental Medicine.
“If you look at the inside of the crown, it has the natural anatomy of a tooth, and the lingual surface has greater reduction than on the facial. You have to make the prep look like the inside of the crown to get the crown to seat down straight all the way,” he says.
Go below the gumline
Continue making slices around the circumference of the tooth. To ensure proper fit, it is necessary to take the cuts below the gumline.
“We do go sub-gingival,” Dr. Jason says. “Some people are a little bit scared of going underneath the gums because they think it’s going to create blood. In order to have the crowns fit properly, you have to go sub-gingival a little bit.”
It’s also important to make sure there are no ledges. Thanks to the tapered design of the #700 bur, holding the bur parallel to the long axis of the tooth avoids creation of ledges.
“The gums are going to bleed. It’s part of the preparation,” says Dr. Josh. “At the end, the crowns get cemented and the gums stop bleeding in half an hour and you have a beautiful looking tooth—where the alternative would be to have taken that tooth out.”
Prevent future pain
After the tooth is prepped, evaluate it for any remaining decay. The Breslers take an aggressive approach to removing decay in their pediatric patients in order to prevent future problems with the restoration or, worse yet, pain and a possible root canal for the patient. If the young patient is properly numbed, their experience in the chair is the same whether you prep conservatively or aggressively.
If the pulp is exposed, perform a pulpectomy. The Breslers access the nerve using a size 80 file. They insert a Formasol-Creosol pellet and use Vitapex®, an injectable root canal material that is also bactericidal, drawing back the syringe to avoid overfilling. Finally, they cap it off with zinc oxide eugenol (ZOE).
Depending on the amount of decay, the crown prep process can take as little as 30 seconds per tooth.
“The prep for anterior crowns is very simple, very easily repeated, and the results are almost always the same,” says Dr. Jason.
For more information on working with Cheng Crowns, view our Cheng Crowns Academy How To Videos.