What is a bridge?
A dental bridge replaces spaces when teeth are lost. Bridges are known as a ‘fixed option’ as unlike dentures, they cannot be removed at home.
Dental bridges are so-called because they traditionally replaced a space between two teeth. This meant that the false tooth (known as a ‘pontic’) could be attached to the natural teeth and was suspended between them.
How can they attach?
There are number of ways that modern bridges can now be supported. A tooth which provides attachment is known as an ‘abutment’.
Crowning the abutment
Crowns are sometimes called ‘caps’. They are thin, tooth-shaped shells made of many possible materials (see the full article on crowns). In these bridge situations, the false tooth is fused to a crown placed on a natural tooth which is next to the gap.
The disadvantages of this option is that to fit the two crowns on each end, the natural teeth must be filed down to make space for their crown’s thickness. This ultimately means that two, healthy teeth must be prepared as an expense to closing a one-tooth gap.
The advantage of this technique is that typically the bridge is stable. As long as the abutment teeth stay healthy, the bridge is held stationary as it is well-supported at both ends.
Sticking to the abutment
To minimise damage to otherwise healthy teeth, adhesive bridges are sometimes a suitable option. Instead of the abutment tooth being crowned, a strong cement attaches the bridge to a neighbouring tooth instead. The reliability of this type of bridge depends on the strength of the adhesive and the force the bridge receives throughout the day. Even with the strongest cements, this type of bridge is said to have the shortest life if subject to high forces.
If natural teeth to act as bridge abutments are not present, dental implants are an option to anchor the bridge (see the full article on implants). In implant-supported cases, a bridge can connect to the implants. This means that more teeth appear in the mouth than there are implants (a 1:1 ratio is not needed). Implants are strategically placed with spaces between them; a bridge arches over the space and the loading forces are shared between the implants beneath.
What is the process for treatment?
Your dentist will examine the space to see the type of bridge which is most suitable for you. If the planned bridge is to be connected to natural teeth, the gum health and bone health of these abutments will be assessed. This could require a new X-ray. Some teeth may require root canal treatment to be considered for bridge abutments (see the full article on root canal treatment).
Most bridges are made on a stone model of your teeth. To create this stone model, the dentist will take an impression which forms a mould of the mouth. A mould may be required before treatment starts for assessment and then an updated mould once necessary tooth preparations have been made.
The bridge is made to your dentist’s requirements, often off-site. At the final visit, it is cemented into place. Patients can therefore expect multiple visits to have a bridge constructed and fitted. Once the bridge is cemented, it can only be removed by a dentist.
How do I care for a bridge?
Regular brushing and hygiene measures should remain part of the daily regime. In order to maximise the success of a bridge once placed, some specific measure should also be adopted. The false tooth permanently sits close to the gum, this means that it is important to keep clean beneath it and prevent anything being trapped. Your dentist or hygienist will likely demonstrate a flossing technique which passes underneath the false tooth. A bridge may be expensive but will last for many years when cared for correctly.
What affects the price of a bridge?
The term ‘units’ is used to describe the number of teeth present on a bridge. Larger unit bridges tend to be more expensive. The material of any bridge attachment will also affect the price. An adhesive bridge may only require a small metal wing to extend from the false tooth whereas other bridges may have multiple crowns for attachment. Crowns can be made entirely of specialised porcelain or may be constructed from porcelain overlying a precious metal. The laboratory which makes the crowns will vary in price as well as the dentist placing it.
Any preparation treatments required will also influence the effective cost of the bridge. This sometimes includes deep cleaning around the gums or more extensive root canal treatments and implant placement for abutments.
Why might I fill a tooth space and what other alternatives are available?
Leaving a gap from a missing tooth is always an option. Sometimes however there are several reasons why it is desirable to occupy a space. This includes problems when eating, problems with speech or when aesthetics are affected. When there are spaces in the mouth, the other teeth may also drift or tilt. Having a false tooth closing this space will prevent unwanted movements.
Your dentist may advise that a bridge is unsuitable in some cases. This can be if the teeth are not positioned favourably, there are large areas with multiple teeth missing or you may be likely to lose more teeth in the close future. Alternatives to the bridges in these cases may include partial dentures or single dental implants.