Dental Bridges

We have bridges that span streams, traverse gorges, soar over bays and connect the banks of rivers around the world. Yet there is another more humble bridge that has had an impact on human society equal to that of the Golden Gate or Rialto. That piece of engineering genius is the dental bridge.

Like other bridges, dental bridges span a gap -- in this case, a gap in the mouth caused by the loss of one or more teeth. It is a much-needed piece of dental hardware; statistics show that 69 percent of adults aged between 35 and 44 have lost at least one tooth either through an accident, decay, gum disease or a failed root canal [source: American Association of Oral and Maxillofacial Surgeons].

While replacing a missing tooth might seem merely like a cosmetic concern, the fact is that even just one AWOL chomper can have a serious impact on dental health. That's because teeth need each other to stay in proper position. So when one goes missing, the opposing and neighboring teeth can begin to shift out of position, potentially leading to a misaligned bite, problems with the temporomandibular joint (TMJ), and an increased risk of tooth decay and gum disease.

Dental bridges range between $500 and $900 per tooth depending on their complexity and materials, and dental insurance typically pays for half the cost [source: Johnstone]. The materials that comprise bridges include porcelain, porcelain fused to metal (PFM) and all gold. Of these, PFM and gold bridges are the strongest and are most often used for back teeth where aesthetics aren't a concern. All-porcelain bridges work well for front of the mouth as they can blend nicely with the surrounding teeth. Depending on the location in the mouth and the amount of pressure placed on bridges, their longevity can vary, although it is not unheard of to have a bridge last as long as 20 years [source: Johnstone].

Next: The three major types of dental bridges.

Types of Dental Bridges

There are three primary types of dental bridges, but the concept behind all of them is the same: Either one or several artificial teeth known as pontics are placed in the mouth and anchored to implanted posts or neighboring teeth (known as abutments). They literally bridge a space between two teeth.

A fixed bridge contains a crown at either end with one or more false teeth attached between them. The crowns slip over the natural teeth found immediately to the right and left of the gap made by missing teeth, and the bridge's false teeth rest on the gums. This is a very durable bridge that's appropriate for placement anywhere in the mouth.
A resin-bonded bridge -- also known as a Maryland bonded bridge -- contains false teeth that span a gap in the mouth. But in this case, the false teeth are attached via metal bands that are glued to neighboring teeth instead of anchored with crowns. It is a viable option when the anchoring teeth are still in good shape and don't need to be restored through the crowning procedure. It is also often used in the front of the mouth where the stress is minimal and the metal bands can be hidden behind the teeth. It is a less invasive process, although the bridge itself isn't as secure as a fixed bridge.
A cantilever bridge is similar to a fixed bridge except, instead of anchoring to a tooth on either side of the gap, it attaches to only one tooth. This might be used in the very back of the mouth where there is only one tooth to which the bridge can anchor, or anywhere there is only one healthy tooth to which the bridge can attach.

Dental Bridge Procedure

As with all bridges (large or small), the key to success is planning, which in this case, means a visit to your dentist. He or she will evaluate your overall dental health and decide whether or not you're a good candidate. If your gums and teeth are in reasonably good health and no gum disease is present, your dentist will green light you for the bridge procedure.

In creating a fixed or cantilevered bridge, the dentist first numbs your mouth in the area where the bridge will eventually be inserted. He then prepares the teeth that will anchor the bridge, which usually involves shaving them down so that the crowns will fit over them. If the teeth are in poor shape, however, he might need to first build them up.

Once the teeth are prepared (which is not necessary for a resin-bonded bridge), the dentist will take a mold of your mouth using a soft putty. This mold is then sent off to a lab so that the bridge can be manufactured. In the meantime, the dentist will fit you with a temporary bridge to protect the exposed teeth and gums. When the permanent bridge is ready, you will return to the dentist's office, the temporary bridge will be removed and the permanent one set in place with super-strong cement.

Dental Bridges vs. Dental Implants

Unlike bridges that anchor to existing teeth and place false teeth on top of the gum line, dental implants actually fuse to the bone in the jaw. A dental implant consists of three parts -- a titanium implant that anchors to the jawbone, a post (also known as an abutment) that protrudes from the anchor through the gum line, and a crown that covers the post with a reconstructed tooth.

Dental implants provide a much more permanent solution to missing teeth. They also have the added benefit of preserving neighboring teeth. This is not only because existing teeth don't have to be altered to accept the crowns attached to a bridge, but because -- according to the American Association of Oral and Maxillofacial Surgeons -- up to 30 percent of the teeth located next to a fixed bridge fail within five to seven years.

Dental implants are nearly twice as expensive as bridges however, and can run between $1,250 and $3,000 per tooth, so the potential benefits of implants must always be weighed against their cost [source: aboutcosmeticdentistry.org].

Lots More Information

Sources

AboutComesticDentistry.com. "Dental Implants." http://www.aboutcosmeticdentistry.com/procedures/dental_implants.html
AboutCosmeticDentistry.com. "What is a Dental Bridge?" (Nov. 19, 2011) http://www.aboutcosmeticdentistry.com/procedures/dental_bridges/index.html
Albright, Sharon. "Dental Bridges." (Nov. 19, 2011) http://www.sharonalbrightdds.com/dental_facts/dental_bridges.html
American Association of Oral and Maxillofacial Surgeons. "Dental Implants." (Nov. 19, 2011) http://www.aaoms.org/dental_implants.php
Colgate Oral and Dental Health Resource Center. "What are Dental Crowns and Tooth Bridges?" (Nov. 19, 2011) http://www.colgate.com/app/CP/US/EN/OC/Information/Articles/Oral-and-Dental-Health-Basics/Checkups-and-Dental-Procedures/Crowns-Bridges/article/What-are-Dental-Crowns-and-Tooth-Bridges.cvsp?showlogs=true
Daily Motion. "Dr. Wade Harrouff answers Dental Bridge Procedure Questions." (Nov. 19, 2011) http://www.dailymotion.com/video/xdwlp8_dr-wade-harrouff-answeres-dental-br_school
Dentistry.com. "Dental Bridge: A Permanent Fix For Missing Teeth." (Nov. 19, 2011) http://www.dentistry.com/conditions-dental-restorations/dental-bridge-a-permanent-fix-for-missing-teeth
EveryDentist.com. "Bridges." (Nov. 19, 2011) http://www.everydentist.com/bridges.asp#Overview
Griffiths, Jackie. "What is a dental bridge?" Private Healthcare UK. July, 2008. (Nov. 19, 2011) http://www.privatehealth.co.uk/articles/july-2008/what-is-a-dental-bridge/
Johnstone, Greg. "Bridging the Gap with a Dental Bridge." Consumer Guide to Dentistry. Nov. 8, 2011. (Nov. 19, 2011) http://www.yourdentistryguide.com/bridges/
sharecare.com. "What are the advantages of a removable dental bridge?" (Nov. 19, 2011) http://www.sharecare.com/question/what-advantages-removable-dental-bridge