Replacing a missing tooth
What happens to the teeth either side of the gap when you get a bridge?
They are reshaped and crowned. A traditional bridge is a single unit: crowns over the two neighbouring teeth, carrying a false tooth between them. It is cemented in place permanently and cannot be removed at home.
What is a traditional bridge made of?
Three connected parts, made as one piece. The false tooth in the middle is called a pontic. The two teeth either side of the gap are the abutments, and each carries a crown. The crowns and the pontic are joined, so the whole thing is fitted and cemented as a single unit.
That is why it does not move and why you cannot take it out. The bridge is held by the two crowns, and those crowns are cemented onto prepared teeth.
The pontic rests against the gum but is not attached to it and has no root. This has one practical consequence that matters more than any other: you must be able to clean underneath it.
What happens at each appointment?
The sequence is fixed, and each stage depends on the one before it.
- Assessment. The two abutment teeth are examined with radiographs to confirm they are strong and healthy enough to carry the load of a third tooth. If either has decay, a failing filling or gum disease, that is treated first — a bridge built on a compromised abutment fails at the abutment.
- Preparation. Once the abutments pass, they are reduced to a tapered shape so the crowns can seat over them. This is the irreversible step, and it is permanent.
- Digital scanning. Detailed measurements are taken with an intraoral scanner rather than putty impressions, and the scan is sent to the laboratory that will fabricate the bridge.
- Temporary crowns. The prepared teeth are covered with temporaries while the bridge is made. These protect the teeth, prevent sensitivity and hold the space so nothing drifts.
- Fit and cement. The finished bridge is tried in, the fit at the margins and the bite are checked and adjusted, and it is then cemented in place.
Between preparation and fitting you wear temporary crowns. Avoid sticky and very hard foods on that side during this period — a temporary that comes off allows the prepared teeth to move, and the bridge may then not seat.
Why do the neighbouring teeth have to be reduced?
Because a crown works by fitting over a tooth, and a tooth is wider at the top than the space a crown needs. To seat a crown, material has to come off every surface of the tooth so the crown can slide over it without ending up bulkier than the original.
That reduction is not treating anything. The abutment teeth may be perfectly healthy; they are being cut because the restoration needs the room. Tooth structure does not grow back, and once two teeth have been prepared for a bridge, they will need crowns for the rest of their lives.
This is not an argument against bridges — they are well proven and there are cases where a bridge is clearly the right answer. It is an argument for asking the question first. If the neighbouring teeth are sound and untouched, a fibre-reinforced bridge or an implant may achieve the same result without committing them. If those teeth already have large restorations or already need crowns, the calculation changes entirely and a bridge may be the most sensible use of the preparation.
How does a bridge compare with a fibre bridge or an implant?
A traditional bridge is the most established of the three, generally the most robust across a wider span, and it is finished within a few weeks rather than months. Its cost is the two abutment teeth.
A fibre-reinforced bridge replaces the same tooth by bonding to the neighbouring teeth with a shallow retention groove instead of full crown preparation. It is far more conservative and usually a single appointment, but it is more sensitive to span length and to a heavy bite.
An implant involves neither neighbouring tooth. It also preserves the bone in the area of the missing tooth, which a bridge does not — the bone under a pontic is no longer being loaded and gradually resorbs. Against that, an implant needs surgery, adequate bone and several months of healing.
The practical decision usually turns on the condition of the two teeth either side. Healthy and untouched argues against a traditional bridge. Already crowned or heavily filled argues for one.
How do you clean under a bridge?
This is the part that decides how long a bridge lasts, and it is the part most often skipped.
Ordinary floss cannot be used, because the three units are joined and there is no gap to pass floss through from above. Instead the space beneath the pontic and between the units must be cleaned from the side, daily, using a floss threader, superfloss, an interdental brush or a water flosser.
If that space is not cleaned, plaque accumulates at the crown margins on the abutment teeth. Decay under a crown margin is the most common way a bridge fails, and because it is hidden under the crown it is usually well advanced before it is noticed.
Beyond that: brush twice daily, keep to routine check-ups so the margins can be inspected radiographically, and mention any change in how the bridge feels when you bite.
How long does a bridge last, and what makes them fail?
Bridges are long-established restorations and many serve for a long time, but none is permanent and the practice will not quote a number that has not been verified for its own cases.
The failure modes are well understood. Decay at the crown margin on an abutment tooth is the most common, and is a cleaning problem. Loss of cement seal on one abutment while the other holds is the most insidious, because the bridge stays in place while decay progresses underneath. Fracture of the bridge itself, or of an abutment tooth under load, accounts for most of the rest, and is more likely if you grind.
When a bridge does fail, the options are narrower than they were the first time, because the abutment teeth have already been reduced. That is worth weighing at the outset rather than at the point of failure.
If a bridge ever feels loose, or one side feels different when you bite, have it looked at promptly. A partially debonded bridge can look and feel almost normal while decay progresses under the loose crown.
Common questions
Does getting a bridge hurt?
The preparation appointment is done under local anaesthetic and should not be painful. Some sensitivity to hot and cold in the following days is common while the temporaries are in place, and it usually settles once the bridge is fitted.
How many teeth can a bridge replace?
It depends on the span and on how strong the abutment teeth are. A single pontic between two sound abutments is the most predictable arrangement. Longer spans place substantially more force on the abutments, and beyond a point implants or a partial denture become the safer choice.
Can a bridge be removed if there is a problem?
Not without destroying it. A cemented bridge is sectioned and cut off, and a new one is made. This is one of the practical differences from a bonded fibre bridge, which can often be repaired in place.
Will a bridge look natural?
Modern bridges are shade-matched and, where the pontic is contoured to meet the gum properly, generally look natural. The most common giveaway is not colour but the gum line, since bone under a pontic recedes over time and a small gap can appear.
What if only one tooth beside the gap is healthy?
A conventional bridge needs support at both ends, so this changes the plan. Options include an implant, a partial denture, or in some cases a bonded design. This should be assessed with radiographs rather than assumed either way.