Advice for patients requiring crowns
A crown is like a special sleeve made of metal or porcelain, or both, that goes over a damaged or weak tooth. Your dentist will match it up to the shape – and, in the case of porcelain crowns, colour – of your other teeth so it will look natural. The crown will probably last for many years, depending on the health of the tooth underneath, and depending on how you look after your mouth.
If a tooth has been broken or weakened by a lot of decay or a large filling, you can have a crown (or cap) fitted to strengthen it and improve its appearance.
Your dentist will take an X-ray to check your tooth. Crowns are shaped like natural teeth and fit over the prepared tooth. For teeth near the front of the mouth, crowns are usually made of ceramic materials which give a very natural appearance. Crowns on back teeth may be made of porcelain or gold, or porcelain bonded onto gold. Gold crowns can either be gold or silver in appearance.
Newer ceramic crowns look like porcelain crowns and are strong enough to be used in all areas of the mouth.
Your dentist will give you a local anaesthetic injection to numb the tooth
The dentist will shape the tooth so that, with the artificial crown, it will be the same size as a normal tooth. Preparation time will depend on how damaged the tooth is and whether it needs to be built up with a filling. The tooth might have to be root-filled first – this is sometimes called ‘removing the nerve’. The crown is sometimes held in place by a peg in the root canal if a lot of the tooth is missing.
Your dentist will use a soft mouldable material to make an exact ‘impression’ of the tooth that is to be crowned and the nearby teeth. A dental technician uses the impression to make the crown the exact height and size needed. A thin cord may be used to hold the gum away from the tooth so that the impression is accurate round the edges.
It will take two weeks for the crown to be ready, so your dentist will fit a temporary one. You will need to be careful biting on the temporary crown as it is only made of a plastic material and is held on with a temporary cement. Food which is particularly sticky or hard could break the temporary crown. At the second appointment, your dentist will take off the temporary crown and cement the new one in place. A small amount of adjustment may be required to ensure your bite is correct.