Why is a Crown required?
The most common reasons are but not confined to
Insufficient tooth structure to hold a direct restoration such as a composite (white) or an amalgam (silver) filling.
More than one of the cusps have broken/undermined/weakened.
If the tooth has had a root canal treatment.
If you are unhappy with the shape/size /colour of the teeth.
After a crown lengthening procedure
Decay or fracture into the gums thus making it difficult for a direct filling.
It can also be more than one unit, as part of the full mouth rehabilitation where we are changing the OVD of the mouth to lengthen the teeth or to correct the occlusion (bite).
What does the treatment involve?
This treatment involves 2 stages and 2 appointments to complete. The first appointment is for the preparation of the teeth to receive a crown and the second is for the fit of the crown.
Crown preparations and sometimes the fit of the crown would be done under local anaesthesia.
We initially have to remove any old restoration, which is compromised or has decay underneath, and make sure the tooth is restorable. Then the remaining tooth is developed as a “core” that holds the crown. The tooth is then conservatively prepared with minimum destruction using high speed and speed increasing handpiece and burs. (Drills)
Once the tooth is prepared and has a sufficient gap for the material of choice of the crown to have sufficient strength and good aesthetics and to cover and protect the teeth.
We will take some impressions of the prepared tooth and arch and the opposing arch, we will then record how the teeth meet in occlusion and decide on a shade.
These impressions and information are then sent to a lab to be processed with a prescription of what is required.
We will make a temporary crown and will cement it with temporary cement at the first appointment. The temporary crown can last for up to 6 months if the treatment requires it, however, it will usually be replaced with the definitive crown in 3 weeks.
The second appointment involves removal of the temporary crown and restoration of the tooth with a definitive crown with the cement.
Sequence for crown preparation procedure -When a tooth is broken badly enough that it needs a crown, we first have to remove old restoration for assessment of restorability, build up the core if there is insufficient tooth structure and then make impressions, which the lab casts up and makes a crown. The patient leaves with a temporary crown in place for usually 2/3 weeks. When we receive this we make some minor adjustments and cement the crown onto the prepared teeth at the fit appointment.
Does the crown preparation hurt?
Patients are frequently afraid to have dental treatment, especially invasive treatment like a crown, please be reassured that the tooth will be completely anaesthetised before treatment.
The treatment should not feel any different from having a normal filling, during treatment you will not feel anything other than the sound and water and buzz of the drill.
Is the Local anaesthetic very painful?
Local anaesthetics are injections given mostly adjacent to the teeth being worked on which is usually a sharp prick and slight discomfort, I usually use a topical anaesthetic gel and a good injection technique that you would hardly feel it.
Occasionally deep injections also have to be given for fillings/tooth preparations if these localised injections do not work well, these are not the most pleasant but would be over in seconds.
Will the tooth be painful after crown preparation?
It is normal to experience some pain/discomfort a few days following a crown preparation. Painkillers such as Ibuprofen or Paracetamol may be needed and will be sufficient to control any pain and/swelling after treatment.
Teeth are frequently tender on biting for a few days, which can take up to a few weeks to a few months to settle down. If on preparation this happens we will leave the teeth in temporary restorations until the tooth settles before proceeding to a definitive crown.
How long does the treatment take?
This procedure is usually carried out in two visits. On the first appointment, we prepare the tooth and take impressions to send to the lab, you will have a temporary in place while waiting for the finished product.
On the second visit we take the temporary off which might involve drilling, the procedure will be done under local anaesthetic. The new crown will be tried on and adjusted if necessary and cemented or bonded to the tooth as required by the material of choice.
What are the alternative treatment options?
We could try simple fillings with either composite (white) or amalgam (silver ) materials
Inlays if it is back teeth and Veneers if it is a front tooth.
Onlay if a single cusp is missing and Overlay if all the cusps need protection.
Although these are alternative options, these may not be suitable for you and which is why a crown would have been advised for this tooth. If no treatment is provided then the condition could worsen and may cause personal injury including the loss of this tooth, severe pain, localised infection and also severe swelling and other infections.