As we enter clinic, it’s not uncommon that providers see patients with missing anterior teeth. Congenitally missing lateral incisors have been reported in a significant percent of the population. For those who have already studied for part 1 of NBDE, we remember that dental decks flash card that states the lateral incisor is actually the third most commonly congenitally missing tooth, behind the third molars and mandibular second premolars. To bridge the gap I, for one, would not opt to do a PFM bridge, reducing anywhere from 0.5-2mm of tooth structure from virgin adjacent teeth. However an implant, which would be the alternative to a bridge, can easily cost upwards of $5,000 each. The other option of a flipper or stayplate may be available for some, but the removable prosthesis makes it less appealing than a fixed option.
As I was paging thru the July 2014 issue of Dentistry Today, I stumbled upon a case report done by Ronald S. Carlson entitled, “Preformed Design Bridging Concept: A Case Report.” The study explores the possibility of replacing a missing anterior tooth with a prefabricated composite tooth, anchored by layered composite over the non-prepped adjacent teeth. Other dentists have done this similar technique by attaching denture pontics with reinforced fibers bonded to the teeth. The denture pontic, however would not chemically bond to the composite. This new composite tooth actually can chemically and mechanically bond to the composite, and therefore the adjacent teeth, making it stronger.
The idea behind the bridge is that it provides an alternative option for patients with a missing tooth. Many patients are concerned with drilling the healthy tooth enamel of supporting teeth. The prep-less bridge offers a less invasive, lower cost option. Whether it be a temporary fix or long term, the option is worth exploring. Another study on using the bridge as an interim prior to implant placement can be found here.
In clinic we are always advised to go over the risks, benefits, and alternatives (RBA) of a treatment plan with the patient. After reading the article and doing some further research online, I realized how the prep-less bridge could be a realistic alternative for some of my patients. In the sim lab during our first and second year, we practiced making traditional PFM bridges as well as fabricating implants for our mannequins. The prepless bridge is a technique we were not taught, so I wanted to try it out for myself.
Although I didn’t have the prefabricated winged pontic, it was easy to make myself. Color match the composite based on the other anterior teeth. For my case, the color match to the plastic teeth was pretty off (since typodont teeth are unrealistic!). I used heavy body polyvinyl siloxane and typodont tooth method, where the tooth is pressed into a cup of PVS and then removed, creating a template for the pontic. Composite was layered and light cured. Once set, the composite pontic pops out.
The next part is to etch and bond the supporting teeth areas. The pontic tooth is tried in and adjustments are made to accommodate the gumline. Small amounts of composite are placed on the adjacent teeth on the side of the missing tooth. The draw of the pontic is established and inserted.
Finishing and polishing. The hardest part here was obviously to get the contacts to look slightly more natural. However, the tooth was only held in place by the composite between the teeth, so I had to keep it heavier.
Some things I found challenging about the method was that the overall appearance was just OK. In the article, they never really showed a full front view. I included a photo of mine, which gave me a clear look at how the teeth that served as support for the pontic were now bulkier. Also, I am not sure how the over all strength of the restoration would be.
What do you think about this technique? Let us know in the comments below!
~Chris Berguia, San Francisco, ’16