A 3-unit bridge is a fixed dental restoration that replaces one missing tooth by anchoring an artificial tooth to the two natural teeth on either side of the gap. It’s the most common type of dental bridge, consisting of three connected pieces: two crowns that fit over your existing teeth and one false tooth (called a pontic) suspended between them. The entire structure is cemented permanently in place, so it looks and functions much like your natural teeth.
How a 3-Unit Bridge Works
The bridge has three parts that work together. The two outer pieces are crowns, sometimes called abutment retainers, that slide over your natural teeth on each side of the empty space. These teeth bear the chewing forces that the missing tooth once handled. The middle piece, the pontic, fills the gap where your tooth used to be. A connector joins each crown to the pontic, creating one solid unit.
Because the bridge distributes biting pressure across two supporting teeth, the forces need to stay within a range those teeth can handle without damage. This is why your dentist evaluates the health and strength of the neighboring teeth before recommending a bridge.
Traditional, Cantilever, and Maryland Bridges
A traditional 3-unit bridge, with crowns on both sides of the gap, is the most common and most stable design. It works when you have healthy natural teeth on each side of the missing tooth. But it’s not the only option.
A cantilever bridge anchors to just one adjacent tooth instead of two. This makes it useful when teeth exist on only one side of the gap, but it places extra stress on that single supporting tooth. A Maryland bridge (also called a resin-bonded bridge) takes a more conservative approach: instead of full crowns, it uses a metal or porcelain framework bonded to the back of the adjacent teeth. Maryland bridges preserve more of your natural tooth structure and are most often used for front teeth, where chewing forces are lighter.
What the Procedure Looks Like
Getting a 3-unit bridge typically takes two visits spread over a couple of weeks. At the first appointment, the two teeth flanking the gap are reshaped, removing enough enamel so that crowns can fit over them. Your dentist takes impressions or digital scans of the prepared teeth, which a dental lab uses to fabricate the bridge. A temporary bridge covers the reshaped teeth while you wait.
At the second visit, the temporary is removed and the permanent bridge is tried in. Your dentist checks the fit, shape, and how your bite aligns, making small adjustments before cementing the bridge permanently. You can expect one to two weeks of mild soreness and sensitivity to hot or cold foods as your mouth adjusts. Cold compresses and over-the-counter pain relievers handle the discomfort for most people.
Materials and How They Compare
The material your bridge is made from affects both how it looks and how long it lasts.
- Porcelain-fused-to-metal (PFM): A metal core covered in porcelain. It combines reasonable strength with a natural appearance, though the porcelain layer can chip under heavy chewing.
- All-ceramic (zirconia or lithium disilicate): These high-strength ceramics rival metal in durability while looking virtually identical to natural teeth. Zirconia bridges are increasingly popular for both front and back teeth.
- Metal alloy (gold, cobalt-chromium, nickel-chromium): The strongest and longest-lasting option, but the metallic color makes them a poor choice for visible teeth. Best suited for molars where aesthetics matter less.
For front teeth, porcelain and ceramic are the go-to choices because they mimic the translucency of natural enamel. For back teeth that take heavy chewing forces, zirconia or metal alloys hold up better over time.
How Long a 3-Unit Bridge Lasts
Most dental bridges last between 5 and 15 years. The material plays a significant role: porcelain and ceramic bridges average around 5 to 7 years, while gold and metal alloy bridges can last 15 years or longer with good care. Your oral hygiene habits, how much force your bite generates, and how well the bridge was fitted all influence its lifespan.
For comparison, a systematic review found that implant-supported 3-unit bridges and tooth-supported 3-unit bridges have similar survival rates. Single implant crowns have a slightly higher 5-year success rate (around 95%) compared to traditional tooth-supported bridges (around 84%), though individual results vary widely based on the patient’s oral health.
3-Unit Bridge vs. Dental Implant
The main alternative to a 3-unit bridge is a single dental implant, which replaces the missing tooth without touching the neighboring teeth. An implant is a titanium post placed into the jawbone, topped with a crown. It preserves the adjacent teeth completely, and plaque control tends to be easier since there’s no pontic to clean under.
A bridge makes more sense when the neighboring teeth already have large fillings or crowns, since they’d benefit from being covered anyway. It’s also a faster process (weeks instead of months) and doesn’t require surgery. An implant is generally preferred when the adjacent teeth are healthy and untouched, though it requires adequate jawbone density and a longer healing timeline.
Common Complications
The most frequent issue with a 3-unit bridge is decay forming at the edges where the crowns meet the natural teeth. If the bridge doesn’t fit precisely, bacteria can accumulate at those margins and cause cavities underneath the crowns. An ill-fitting bridge can also irritate the gums, leading to inflammation, bleeding, and eventually gum disease if left untreated.
During tooth preparation, there’s a small risk of nerve damage to the abutment teeth. This is uncommon, but it can cause temporary or, in rare cases, permanent changes in sensation. Bone loss around the pontic area is also possible over time, since the jawbone beneath the false tooth no longer receives the stimulation it got from a natural tooth root.
Signs that something is wrong include persistent pain around the bridge, sensitivity to hot or cold that doesn’t fade after the initial adjustment period, swelling or tenderness in the gums, or difficulty chewing.
Cleaning and Daily Care
A bridge requires more deliberate cleaning than natural teeth because food and plaque collect in the space between the pontic and your gums. Regular floss can’t pass through a connected bridge, so you’ll need specialized tools.
A floss threader is the most basic option: you thread a piece of floss under the pontic and gently slide it back and forth to clear debris. Interdental brushes, small enough to fit under the bridge, clean the sides of the crowns and the space beneath the pontic. A water flosser uses a pressurized stream to dislodge particles and is especially helpful if you find threaders awkward to use. Finishing with an antibacterial mouthwash helps reduce bacteria in areas you may have missed.
Consistent cleaning under the bridge is the single most important thing you can do to extend its lifespan and prevent decay at the abutment teeth.
Cost of a 3-Unit Bridge
The national average cost for a traditional 3-unit bridge is roughly $5,200 without insurance. Depending on your location and the materials used, the price typically falls between $3,000 and $6,500. Metal bridges tend to cost less than all-ceramic options, and prices are generally higher in major metropolitan areas. Most dental insurance plans cover bridges as a major restorative procedure, typically at 50% after your deductible, though coverage varies by plan. Many dental offices also offer payment plans or financing through third-party providers.