When the cavity or defect in a tooth is too large, a normal filling may not be the best long term restoration.

Crowns as their name suggest are caps or "helmets" which sit upon the weak tooth to protect it and also restore your smile. It takes two appointments to place a crown. 

At the first appointment, the tooth is prepared and any decay removed. A precise mould is taken and a temporary crown made. The mould and other records are then sent to a dental laboratory where the crown is custom crafted for the tooth. 

The second appointment involves adjusting and fitting the crown to precisely fit the tooth. Once everything is fine, the crown is then cemented into place.

Bridges are used to span areas of the jaw where teeth have been extracted or are naturally missing. 

They are like crowns in the way that they are constructed but they are essentially 2 or more crowns joined together with 1 or more false teeth in between. Alternatives treatments to bridging are dentures and implants

Both Crowns and Bridges can either be made in metal (eg Gold) , porcelain or a combination of the two.