Twenty Years of Faithful Service, Then the Bridge Turned on Him

Quick answer: Bridges do not last forever, and they usually fail from underneath. Recurring swelling or a bad taste around an old bridge almost always means decay or infection at one of the supporting teeth, hidden beneath porcelain where neither you nor an x-ray sees it easily.

The call

Ezra, 68, from the merkaz in Old Beit Shemesh, had a three-unit bridge fitted in the early 2000s. Over the previous year he had had three episodes of swelling in the gum beneath it. Each settled with antibiotics. He had also noticed a persistent bad taste and that food was catching underneath.

He came in during the fourth episode, and said what many patients in his position say: he did not want to lose the bridge, because it had been expensive and it had worked well for twenty years.

What we found

The bridge spanned from a canine to a molar, replacing a premolar in between. It was still firmly cemented.

Probing revealed a 7mm pocket at the back abutment, with pus. That tooth gave no response to vitality testing. The x-ray showed a lesion at its root tip, and — visible once we knew to look for it — a dark shadow of decay at the margin under the crown, on the tongue side where it had been quietly progressing for years.

The front abutment, the canine, tested vital and had clean margins.

Why bridges fail this way is straightforward. The junction between crown and tooth is the vulnerable point. Over years, cement can wash out microscopically and the margin becomes a plaque trap. Under a bridge you cannot floss normally — you have to thread floss beneath the false tooth — and most people stop doing it after a few years, if they ever started. Decay begins at the margin, works inwards, and reaches the nerve. By the time it announces itself, it has usually been going on for a long time.

The 20-year lifespan is not unusual. Bridges are not permanent, and the honest figure is that a good proportion need replacing somewhere between ten and twenty years.

What we did

We sectioned the bridge — cut it in two between the false tooth and the back abutment — rather than removing the whole thing. That preserved the front portion temporarily and gave us access to assess the damaged tooth properly.

Underneath, the decay was extensive but had not reached below the bone. The tooth was restorable.

Root canal treatment on the back abutment, then a post and core. Once healed, a new three-unit bridge, and this time we spent time on the design: a slightly different pontic shape that allowed a superfloss threader through easily, and margins placed where he could actually clean them.

We also went through cleaning technique with him properly, which had never been done when the first bridge was fitted. That is the difference between the new bridge lasting twenty years and lasting eight.

The outcome

No further episodes in three years. He uses a threader daily and a water flosser, and comes for a hygienist appointment every four months.

What to do if this happens to you

1. Take recurring swelling around a bridge seriously. It is not a gum problem that keeps coming back; something underneath is failing.
2. Note a bad taste or food catching. Both point to a leaking margin.
3. Ask for the abutment teeth to be probed and vitality tested, not just x-rayed. Metal hides a great deal on a film.
4. Ask whether the bridge can be sectioned rather than removed whole. It sometimes saves part of the work.
5. Learn to clean under a bridge, with a floss threader or superfloss, from the day it is fitted.
6. Have old bridgework checked yearly, even when it feels fine.

Problems with an old bridge or crown? Ramat Beit Shemesh Urgent Dental Care assesses what can be kept before recommending replacement. 055-985-8845 · WhatsApp https://wa.me/972559858845 · Harav Kook 28/1, Beit Shemesh.

Based on real cases treated at the clinic. Names have been changed.