What is a crown?
A dental crown is a tooth shaped cap that sits completely over a tooth or implant. It acts like a helmet against the forces of chewing, protecting the tooth underneath and improving its appearance; giving it back the size, shape and colour to allow you to chew properly. Crowns or 'caps’ are therefore made to cover and protect a damaged, decayed, broken and/or root filled tooth. Usually 2 visits are required. At the first visit the tooth is prepared by removing any decay or damaged tooth and then shaped in readiness to enable a good bonding of the finished crown, impressions are taken of the prepared tooth and a temporary crown is fitted. At the second appointment the temporary crown is removed and the permanent crown is fitted. The appearance and bite are checked and adjusted as necessary.
Our crowns are made from a variety of materials depending on what finish and durability a patient is looking for, as well as the individual case and suitability of the tooth. The dentist will be able to advise you on what is the best solution.
Porcelain Bonded Crown, PBC - Porcelain is bonded to a metal casing, the most common type of crown which combines both strength and aesthetics
All Ceramic or all Porcelain Crowns - no metal present so more aesthetically pleasing results but requires more tooth reduction
Zirconia crown - no metal present, aesthetically pleasing results, very tough material, but requires more tooth reduction
Gold crown-either yellow or white - a gold alloy which is biologically inert, requires less tooth reduction than other crown types but aesthetically more noticeable as not tooth-coloured.
On average a dental crown can be expected to last 10-15 years. But it is not unusual for it to last considerably longer.
The main advantages of having a crown are:
- Aesthetics - The colour and the shape of the tooth or teeth can be improved with crowns. Porcelain has a more natural appearance and is much more resistant to stains than white filling material (composite).
- Protection - They provide the best possible protection to a heavily broken down tooth.
- Long Lasting - Studies have shown that crowns last longer than large fillings. However, nothing is as good as natural teeth, and once a tooth has been prepared for a crown, it will always need a crown- there is no going back.
- Destructive - If the tooth is completely natural, the preparation is quite damaging to the tooth as it involves grinding part of it away. Where the tooth has already been heavily damaged or has multiple or large fillings it can actually have a protective role. Careful consideration of this is needed in treatment planning and treatment acceptance.
- Damaged Nerves 1-15% lose nerve health and will require root canal treatment. For a number of reasons it is difficult to be any more accurate than this. Usually a tooth can be root filled through a crown.
- Higher cost investment - It may be 4 times the cost of a filling, due to the laboratory costs and treatment time
- Multiple appointments - (Approximately two appointments, 50-60mins for preparation of the tooth then 20-30minutes to fit the completed crown)
- Recession can occur at the gum line of the tooth that may in the long term show as a dark line. Although it is still a functioning crown replacement may be needed for aesthetic reasons.
Factors to consider include:
- Poor periodontal support. If the tooth has very little bone holding it in place and is loose, that suggests that the prognosis is not good, the cost of a crown may not be justified. Extraction may be considered although it is not always necessary.
- Unopposed teeth. If the tooth doesn't have another tooth opposite it to chew on and is of little functional use, i.e. it doesn't support a partial denture or provide any value to the mouth, then a filling or an extraction may be considered. If it is opposite a space that is in a useful position, it would be far better to keep the tooth and fill the space to provide extra surface for chewing, thus preventing the effects of missing teeth, such as over-eruption of the teeth opposite the gap, changes to your bite, headaches and jaw joint complaints
- Design to aid home care. Sometimes in hidden areas the join between the tooth and crown is placed above the gum line. This makes the join easier to cleanse, so less irritating to the gum and reduces amount of tooth preparation so optimising tooth strength
A successful crown relies on a good foundation tooth, good preparation from the dentist and most importantly the patient looking after it, implementing correct oral hygiene procedures at home.
It is recommended that patients attend for at least six-monthly prevention and plaque control visits because it is important that good oral hygiene is maintained to keep the crown margins clean and prevent plaque build-up. It is the patient's responsibility to look after the crown at home and maintain good oral hygiene procedures.
Prices from £635.
What is a dental bridge?
A dental bridge is one way to replace a missing tooth or teeth. They restore your smile and your ability to chew and speak. They can also maintain the shape of your face by providing support to the cheeks and lips and prevent other teeth drifting, which can sometimes create problems with the bite and jaw joint. It is a fixed option for restoring the space, meaning it stays permanently in your mouth. Dental bridges literally bridge the gap created by one or more missing teeth.
There are different designs and styles of bridges, but essentially they all use the teeth either side of the gap to hold the fake or bridged tooth (pontic) in the gap to restore your smile and bite.
With good hygiene and diet and regular examinations with the dentist, bridges should last from 5-15 years, and some may last even longer, but it is dependent upon factors such as:
- The quality of the supporting teeth (abutments)
- The design of the bridge chosen
- The length of bridge - the more units (teeth/ pontic’s) and teeth involved, the higher the risk of something going wrong
- The types of material used
- How well you look after it
- The forces you place upon it
Conventional Bonded bridge - This is by far the most common type of bridge. It generally involves crowns either side of the space holding a pontic in the middle.
Adhesive bridges - Here the pontic is attached on one or both sides of the space by metal or porcelain wings. Since they are bonded onto existing teeth without crowning the adjacent teeth, they are only suitable for small gaps and low bite forces.
Your dentist will make the decision on the most suitable type of material, taking into account the bridge design, your teeth, bite, and past experiences.
All porcelain or zirconia – These have no metal substructure and are generally used for aesthetics to replace teeth that are visible when smiling.
All metal - These have the advantage of requiring less tooth to be removed, but the issue of aesthetics means they are rarely used. Precious or non precious metals are used.
Porcelain Bonded – This type of bridge has a metal substructure that is coated in porcelain, this is the most commonly used bridge material and has both benefits of strength and aesthetics. Porcelain fused to metal gives the dentist the added bonus of being able to choose the amount of metal/porcelain. This means where maximum tooth needs to be kept for strength, a metal surface can be used whilst still having the tooth coloured porcelain on the side for aesthetics- a bit of a compromise.
- Short treatment time with usually 2 weeks to fit the bridge after preparation
- No surgery required (unlike implant placement)
- If adjacent teeth are weak there is the added benefit of protecting these teeth from fracture with crowns
- The success of the bridge relies on continued health of supporting teeth that can decay, require root filling or break due to additional loading on them
- The gap under the pontic can appear as bone loss continues after a tooth is removed; this is a much higher risk for bridges placed immediately after a tooth is removed, which is why the dentist may suggest a temporary bridge initially to allow the gum level to settle.
- Recession can occur at the gum line of supporting teeth that may in the long term show as a dark line. Although it is still a functioning bridge, replacement may be needed for aesthetic reasons.
Factors to consider include:
The state of the abutment teeth: These are the teeth to be used to support the bridge.
If they are untouched, the more conservative a bridge the better i.e. the less preparation required on healthy teeth the better.
If the teeth are heavily restored, there is a greater benefit to having a crown/bridge as a protection for the remaining tooth.
If an abutment tooth has had root canal treatment: If one of the supporting teeth has undergone root canal treatment, protecting it with a crown is a good idea anyway so a bonded bridge would be indicated if enough tooth remains to support the additional pontic biting load. However, if it also has a post into the root canal, this reduces the suitability for supporting a bridge as pressures on the bridge can risk the post fracturing the root — this would cause the tooth to be lost and a major rethink would be required. The benefit/risk will be carefully weighed up by your dentist.
Periodontal support: If a tooth has very little bone holding it in place or has mobility, that suggests the long term prognosis is not good, this tooth would not make a good bridge abutment.
Design to aid home care: Sometimes in hidden areas the join between the tooth and crown is placed above the gum line. This makes the join visible but easier to clean, so less likely to create gum irritation. It also means that less tooth needs to be removed when preparing it, so maintaining optimal strength.
It is recommended that you attend for at least six-monthly prevention and plaque control visits because it is important that good oral hygiene is maintained to keep the bridge margins clean and prevent plaque build-up. Use of superfloss or floss threaders is required to clean under the pontic. It is your responsibility to look after the bridge at home and maintain good oral hygiene procedures.
Prices from £780.