The parts of a fixed bridge
These terms explain why a bridge is priced by the number of units rather than the teeth replaced.
- Abutment teeth and retainers
- The natural teeth on either side of the gap carry the bridge. They are prepared for crowns, called retainers, and from then on they carry their own chewing load plus a share of the missing tooth's.
- Pontic
- The false tooth filling the gap. It rests against the gum but is not attached to it and does not enter the bone. A modified ridge lap design touches the gum only on the cheek side, so it looks natural and can be cleaned underneath.
- Connectors and span
- The joins between units are solid, which is why floss cannot pass between the teeth of a bridge. A three-unit bridge is two abutments and one pontic; longer spans flex more and load the abutments harder.
What a bridge asks of the neighboring teeth
This is the honest cost of a bridge, and the part that gets glossed over. To carry the pontic, the teeth on either side are reduced to stumps. Enamel that is removed does not grow back, and those teeth are committed to being crowned from that day on. Preparation also carries some risk to the nerve, and a proportion of prepared teeth need root canal treatment years later.
Two roots now carry the load of three teeth. If one abutment decays under its crown or fractures, the whole bridge usually comes out and you have a longer gap than you started with. The calculation flips when those teeth already have large fillings or crowns, because then they need covering anyway and the bridge costs you nothing extra in tooth structure.
The work is two visits a few weeks apart, much like having two crowns done at once, with a temporary bridge in between.
Cleaning under the pontic is the deciding factor
A bridge is joined together, so floss cannot pass between the units. The pontic sits against the gum and plaque collects underneath, and nearly everything that goes wrong long term starts there.
- A floss threader. A stiff plastic loop that carries floss under the pontic so you can work it against the abutment teeth and the underside of the false tooth.
- Superfloss. One strand with a stiff threading end and a spongy middle that wipes the underside of the pontic. Easier than a threader and floss separately.
- An interdental brush. A small tapered brush that passes under the pontic where there is room, and for many people this is what makes bridge cleaning quick enough to do daily. A water flosser helps but does not replace it.
- Every day, not now and then. Plaque under a pontic causes bleeding gums and decay at the crown margins, and neither hurts until it is advanced.
If you know you will not keep this up, say so before treatment starts. A partial denture or an implant may suit how you actually live. See periodontal care.
Cantilever, Maryland and implant-supported variations
The traditional bridge with an abutment at each end is the standard. Three variants come up often enough to know about.
- Cantilever bridge
- Supported at one end only, with the pontic hanging off a single abutment. That puts leverage on the tooth, so it is limited to light-force situations such as a small upper lateral incisor.
- Maryland or resin-bonded bridge
- A pontic with thin wings bonded to the back of the neighboring teeth. Very little tooth structure is removed, which makes it the most conservative option, and it is often used at the front for a younger patient whose jaw is still growing. The weakness is that the bond can let go.
- Implant-supported bridge
- Two or more implants carrying a bridge with no natural teeth involved, for when several teeth in a row are missing.
A fixed bridge compared with a removable partial denture
When an implant is not on the table, this is usually the choice. Fixed is not automatically better.
| Consideration | Fixed bridge | Removable partial denture |
|---|---|---|
| In the mouth | Cemented in and never taken out. Feels closest to your own teeth. | Comes out for cleaning and overnight. Bulkier, and takes getting used to. |
| Tooth structure | The abutment teeth are cut down for crowns. | Little or none removed, beyond small rest seats in the supporting teeth. |
| How many teeth it replaces | A short span, with sound teeth at both ends of the gap. | Several gaps at once, including gaps with no tooth behind them. |
| Cleaning and appearance | Floss threaded under the pontic daily. No visible metal. | Taken out and brushed, which is easier, but clasps can show and the teeth holding them decay if neglected. |
Bridge questions
How long does a dental bridge last?
Bridges commonly serve for many years and plenty run past a decade. What ends most of them is not the bridge but the abutment teeth underneath, through decay at a margin or a fracture. Daily cleaning under the pontic is the biggest thing in your control.
How many teeth can a bridge replace?
It depends on the span and on the bone support the abutment teeth have. One missing tooth between two sound teeth is straightforward and two in a row is often workable. Beyond that the load on the abutments is the limiting factor.
Which costs more, a bridge or an implant?
What are the alternatives to a bridge?
A single dental implant, which leaves the neighboring teeth untouched, or a removable partial denture. Leaving the gap is also a choice, though the drifting described under restorative dentistry makes it an expensive one.