Crowns and bridges

A crown can make a tooth stronger and improve how it looks (ADA). Crowns are made of metal, porcelain fused to metal, all-ceramic materials such as zirconia, or resin. Resin is often used for temporary crowns (Cleveland Clinic).

A bridge fills a gap with one or more false teeth. The common type holds the false tooth between crowns on the teeth either side. Other types are held by a crown on one side only, by metal wings bonded to the backs of the neighboring teeth, or by dental implants (Cleveland Clinic).

A dentist may suggest a crown to (ADA):

• support a tooth that has too little of its own structure left to hold a large filling
• protect a weak or cracked tooth, or restore a broken one
• cover a badly shaped or discolored tooth
• cover a dental implant or hold a bridge in place

Teeth treated with a root canal often get a crown too (Cleveland Clinic). For a missing tooth, the main alternatives to a bridge are an implant or a partial denture (Cleveland Clinic).

1. Preparing the tooth. The dentist numbs the area and removes some enamel so the crown fits. Some filling material may be added to build the tooth up (Cleveland Clinic). For a bridge, the teeth either side are reshaped. This step cannot be undone (Cleveland Clinic).
2. Impression or scan. The dentist takes an impression or digital scan, and you leave with a temporary crown or bridge (Cleveland Clinic).
3. Lab work. A lab usually returns a crown in two to three weeks (Cleveland Clinic). A bridge usually takes two to four weeks (Cleveland Clinic).
4. Fitting. At the second visit, the dentist removes the temporary, checks the fit and color, and cements the final crown or bridge (Cleveland Clinic).

Some practices design and mill a ceramic crown in the office, so it can be fitted in one visit. Not everyone is a candidate (Cleveland Clinic).

• Some sensitivity to hot and cold is normal for a couple of weeks, and sore gums usually settle within a few days (Cleveland Clinic).
• Avoid chewing ice, very hard nuts and sticky candy (Cleveland Clinic).
• Brush twice a day and floss daily. Clean under a bridge every day with a floss threader or small brushes made to fit between teeth (Cleveland Clinic).
• If you grind your teeth, ask about a custom mouth guard (Cleveland Clinic).
• Call your dentist if a crown feels loose, chips or has a sharp edge, or if you notice a bad taste (Cleveland Clinic).

Possible problems include sensitivity, a chipped or loose crown and, rarely, an allergic reaction. A crown that does not fit well can trap bacteria and lead to decay (Cleveland Clinic). With a bridge, decay or damage to the supporting teeth can weaken it, and a bridge may break if it has to be removed (Cleveland Clinic).

The figures below come from systematic reviews. They describe groups of patients, not what will happen to you.

• Crowns. About 95% of porcelain-fused-to-metal crowns were still in place after five years. Most all-ceramic crowns did about as well. Zirconia crowns had more technical problems, such as chipping of the outer layer and coming loose (Sailer 2015).
• Bridges. About 94% of porcelain-fused-to-metal bridges were still in place after five years. All-ceramic bridges did somewhat less well, at about 86% to 90% (Pjetursson 2015).

Cleveland Clinic says crowns and bridges typically last 5 to 15 years with good care (Cleveland Clinic).

• The material, and whether it is made in a lab or milled in the office.
• How many teeth are involved. A bridge includes the crowns on the supporting teeth as well as the false teeth.
• Any build-up, post or root canal the tooth needs first.
• The temporary crown or bridge.
• What your dental plan covers, and any yearly maximum.

Ask for a written estimate that lists each tooth and each item separately, with its CDT code (ADA). Ask your dentist to send a pre-treatment estimate to your insurer before you start.

1. Why does this tooth need a crown rather than a filling?
2. Which material do you suggest for this tooth, and why?
3. Can it be done in one visit?
4. For a bridge: what will happen to the teeth on either side? Would an implant or a partial denture suit me?
5. How do I clean around it?
6. What happens if it comes loose or breaks, and who pays?