Crowns and Bridges

A crown is a dental restoration that covers the whole tooth like a thimble and usually used to repair and strengthen damaged teeth. They can also be used cosmetically to improve the appearance of teeth. 

Bridges are similar to crowns, but they are used to replace missing teeth. This is done by suspending false porcelain teeth (pontics) over the space from one or more adjacent teeth (abutments). This attachment comes in the form of a crown or metal wing.

There are different materials that can be used to make crowns and bridges, each having its own characteristic advantages and disadvantages. There are also various bridge design option, depending on several factors which your dentist can explain to you.

Metal Ceramic Crown (MCC); (aka pfm porcelain fused to metal) made of a metal core with porcelain bonded over it. It give a good  aesthetic appearance and the metal base provides a strong core that can withstand the pressure exerted on these teeth during chewing. However, in full natural light, the metal base can show through as a shadow in  the tooth, especially on front teeth. Also, if the gums recede, the metal base can be seen as a dark line that  will show where the crown meets the gum.

Ziconium Core Crown: (e.g LAVA) has no metal in it, instead a tooth-coloured zirconia coping is made on a computerised milling machine. Zirconium is a very hard ceramic material and is very strong. Porcelain is bonded over this Zirconium and with no metal underneath. These crowns are more translucent and have better light transmitting properties. This type of crown looks very natural and is the best aesthetic choice, important for front teeth.

Full Gold Crown: is completely made of a gold alloy and hence appears a solid gold colour. Aesthetically poor, but very robust and long lasting. Also the only NHS option for crowns on back teeth.

Full Ziconium Crown: is made completely out of zirconium, so as a result is very, very strong. Mainly used for  people who clench or grind their teeth (bruxists) who would normally fracture normal crowns. Aesthetically good but not as good as the Zirconium core crown, but obviously much better than a gold crown. 

Preparation and Procedure:

The teeth are prepared by removing some of the outer tooth substance to make space for the restoration. An impression is taken of the prepared teeth and sent to a dental technician in a laboratory with a shade to match your own teeth. A temporary crown is usually made and  fitted in the surgery, as it takes between 7-12 days for the crown/bridge to be made. The temporary crown is cemented with a temporary cement so that it can be easily removed by the dentist before the final crown is cemented in place.