Crowns and Bridges

What is a crown and why would you need one?

A crown is a covering that goes over the top of a natural tooth. A crown can be made from a variety of materials but in most cases is made in a material that will resemble the natural tooth. This way the cover of the tooth matches the other teeth and it is not noticeable that it is a crowned tooth.

Crowns are often placed as they are the best way to help strengthen and help maintain a natural tooth for as long as possible. This is mainly done in situations where the tooth has lost the integrity of its structure and has become weak, or is broken or chipped. This can occur to a tooth where the following has occurred:

  • A tooth has undergone root canal treatment in which the pulp of the tooth has been removed. This makes the tooth weaker from the inside hence making the tooth more likely to break or crumble.
  • Where a tooth has a large filling, this is because this weakens the outer structure of the tooth making it likely to break and need continuous repair or causing it to break beyond repair.
  • Where a tooth has lost a large amount of tooth structure due to tooth decay.
  • Where the tooth has suffered any trauma, this can occur from any trauma to the face such as a fall or being hit with a ball, etc.
  • General wear and tear which can occur as a tooth gets older.

What is a bridge and why would you need one?

There are many different types of bridges and their main purpose is to replace one or more missing teeth. Bridges are suitable to be used to replace teeth where a tooth/teeth have been lost and have adjacent teeth still remaining on one or both sides of the gap.

A bridge is designed to replace the missing tooth by consisting of an artificial tooth which is anchored/attached, to the natural tooth or teeth on one or both sides of the gap caused by the missing tooth. Which type of bridge is suitable for your particular situation is best to be discussed with you by your dentist, as not all bridges are capable of being used in every situation.

How long does a crown or bridge last?

How long a crown or bridge will last can vary depending on the integrity of the tooth or teeth underneath, however on average they should last 8-10 years. There is no guaranteed length of time that a crown or bridge will last. The same as it is with your natural teeth how long your crowns and bridges will last will depend on good oral hygiene, specific to your bridges and crowns and regular dental check-ups.

How many appointments will a crown or bridge take?

How many appointments a crown or bridge may take to be completed can vary depending on the practice that you attend and on your particular circumstances. In most situations however it will take on average two appointments to complete a crown or bridge. Your first appointment for your crown or bridge will be your preparation appointment. At this appointment your tooth/teeth will be prepared ready to have the crown or bridge placed. At this appointment the dentist will generally also take impressions of your teeth, this can be done manually or electronically. These impressions are then used to create a crown or bridge specific to you. In some occasions the impressions needed for your crown or bridge may not be able to be taken at this appointment, if that is the case the dentist will inform you off this and impressions will be taken at another appointment.

At your second appointment your crown or bridge will be issued to you if it is appropriate to do so. It is important to mention that although in most cases it is appropriate to issue the crown at the second appointment, in some situations the crown may not fit or may not achieve the desired aesthetic. If this is the case the crown will then have to be modified to properly fit the tooth and another appointment may be required to fit the modified crown at a later time.

What to expect at your crown preparation appointment?

At your crown preparation appointment, you can expect:

  • The tooth and the area surrounding the tooth that is going to be prepared will be numbed using a local anaesthetic.
  • An impression will be taken of the area before the tooth is prepared for the crown, this is to be used later to help the dentist make a temporary crown for you.
  • Once the area is completely numb one to two millimetres of the tooths surface is removed and the tooth is shaped using a drill. This is done to prepare the tooth for the crown to fit over the top.
  • Once the tooth is the appropriate size an impression will be taken of the prepared tooth which will be used to make the crown.
  • After the impressions have been taken the dentist will then use the impression taken prior to the procedure beginning to help make you a temporary crown. This temporary crown will be attached to the tooth with a temporary cement. This is done so that the remaining tooth structure is protected while you wait for your final crown and also to help maintain aesthetics.
  • It is important to remember while you are waiting for your final crown that your temporary crown is not as strong as your final crown will be.

In some situations, other steps may be taken during your crown preparation appointment such as a crown lengthening procedure. If such steps are required, they will be discussed with and explained to you before your appointment.

What to expect at your bridge preparation appointment?

The steps that occur during a preparation for a bridge appointment are very similar to those that occur in a crown preparation appointment. The only way in which they differ is that in these appointments depending on which kind of bridge is being done, there will generally be two teeth prepared. This is because the two teeth on either side of the gap caused by a lost tooth will be prepared.

Will there be any pain or discomfort after your preparation appointment?

In the days following your preparation procedure some sensitivity of the tooth, or some pain or discomfort of the gums around the area is normal. If this pain or discomfort becomes unmanageable, lasts a prolonged period of time or begins to concern you, you should contact your dental clinic.

What to expect at your crown issue appointment?

At your crown issue appointment, you can expect:

  • The temporary crown will be removed from the tooth and the tooth will be cleaned to remove any residual cement.
  • The permanent crown is then tried on to the tooth that has been prepared.
  • While the tooth is being tried on the tooth the occlusion (height), fitness (how well it fits on the prepared tooth) and aesthetic of the tooth will be checked.
  • If the crown fits on the tooth then the crown will be permanently cemented on.

What to expect at your bridge issue appointment?

What to be expected is exactly the same as what should be expected at a crown issue appointment. The process used to issue a bridge is the same.

Possible complications of crown or bridge treatment

As with any dental treatment there are possible complications that can occur, some of the possible complications are:

  • The natural tooth can break

Although upon examination of the tooth your dentist will be able to tell you whether or not your natural tooth structure is strong enough to hold a crown, and although they will do everything in their power to reinforce the tooth, if this is the case it is still possible for your natural tooth to break. The likelihood of this will depend on the tooth as it is possible even after all the treatments available have been exhausted, the tooth may still not be strong enough to withhold the pressure of the bite and may break.

  • The tooth can get an infection in the pulp

Whenever the enamel (outside surface of a tooth) of a tooth is removed there is a risk that the pulp (inner nerve of the tooth) can begin to die. The death of the tooth can in some cases lead to an infection in the gum.

The possibility of this occurring is slight, however other factors such as previous large fillings or symptoms of the tooth dying can affect the likelihood of this occurring.

  • The bridge or crown may become loose

Crowns and bridges when they are fitted correctly should be stable. However, in some situations such as where trauma occurs to the face, a crown or bridge may become loose. Where this occurs in most cases a crown or bridge can be cleaned and recemented. In rare cases the crown or bridge may break and will then have to be replaced.