Replacing a missing tooth: implant, bridge or denture

When the missing tooth is at the back and nobody can see it, the obvious question is why bother. It is a fair question, and the answer has less to do with appearance than most people expect.

What happens if you leave the gap

• The teeth either side gradually tip into the space. A tipped tooth is harder to clean, traps plaque against its neighbour, and is no longer taking bite forces along its long axis, which is what it is built for.
• The tooth in the opposing jaw, with nothing to bite against, over-erupts. It drifts down or up out of its socket, taking gum and bone with it, and can eventually interfere with the bite.
• The bite redistributes. Fewer teeth carrying the same load means more force per tooth, and over years that shows up as wear, cracks and failed restorations elsewhere.
• The bone where the root was begins to resorb.

Option one: a dental implant

An implant is a titanium screw placed into the jawbone to act as an artificial root, with a crown attached on top. After placement, bone grows directly onto the surface of the titanium, a process called osseointegration, which takes roughly three to six months. That healing period is not padding; it is what makes the implant load-bearing.

Its main advantage is that it stands alone. The neighbouring teeth are not touched, not cut down, and not carrying any of the load. It also transmits force into the bone, which slows the resorption that a gap or a denture does nothing about.

The caveat that does not appear in the advertising

Implants get gum disease too. It is called peri-implantitis when it affects the bone and peri-implant mucositis when it is confined to the soft tissue, and it is not rare: across ten-year data, mucositis is reported in roughly 30 to 50 percent of implants.

More importantly, a history of periodontitis raises the incidence of peri-implantitis by roughly four times. If you lost the original tooth to gum disease, the same disease is waiting for the implant, and an implant is in some ways more vulnerable because it has no periodontal ligament and no equivalent blood supply to defend itself.

This is why any honest implant plan begins with getting the gums stable and stays there with maintenance appointments. Smoking is the other major risk factor, and it is worth knowing before you commit rather than afterwards.

Option two: a bridge

A bridge spans the gap by taking support from the teeth on either side. Those teeth are prepared, meaning a layer of the outside of each is removed, and a single unit cemented across all three.

It is faster than an implant, usually a few weeks rather than months, involves no surgery, and it is well proven. The cost is structural: two healthy teeth are permanently reduced to support one missing one, and if the bridge later fails, three teeth are involved rather than one. Cleaning under the false tooth requires a threaded floss or an interdental brush, and neglecting it is the usual cause of failure.

A bridge makes real sense when the neighbouring teeth already have large fillings or crowns, because then nothing healthy is being sacrificed. It makes less sense when they are pristine.

Option three: a denture

A removable partial denture is the least invasive and least expensive option. Nothing is drilled and nothing is surgical. For someone replacing several teeth, or who is not a candidate for surgery, it can be entirely the right answer.

The trade-offs are real. It is removable, it takes getting used to, chewing efficiency is lower, and the clasps can collect plaque against the teeth they grip. Because it rests on the gum rather than in the bone, it does nothing to prevent the ridge underneath from continuing to resorb, and dentures therefore need adjusting or remaking as the shape beneath them changes.

How the choice actually gets made

• How much bone is present, and whether grafting would be needed. This is assessed on an X-ray or a scan, not by looking.
• Whether the neighbouring teeth are healthy and untouched, or already restored.
• Whether gum disease is present and controlled. If it is active, that is treated first regardless of which option follows.
• Smoking, diabetes control and any medication affecting bone healing.
• How many teeth are missing and where. One gap in a row of healthy teeth is a different problem from four scattered spaces.
• Budget and time, honestly weighed against how long each option is likely to last.

There is no option that is best in general. There is usually one that is clearly best for a particular mouth, and working out which takes an examination and a radiograph rather than a price list.