Crowns and Bridges
- Zirconia: Zirconium crowns are the latest and more robust than porcelain crowns. They last longer too, compared to porcelain that chip and break. Zirconium crowns also provide strength without the bulky appearance that porcelain crowns have.
- Gold: Gold is usually used on the back teeth, as it has several advantages over porcelain teeth. Gold is strong in thin section and less tooth needs to be drilled away before taking the impression and fitting the crown. A lab technician finds it easier to use gold as it shrinks less when cast and is easier to polish. Crowns of porcelain shrink when cast and the technician has to estimate this when making the crown.
- Porcelain: Porcelain is usually always used for the front teeth but may be used for the back teeth. This material can be made to appear very natural though several factors affect this. Some porcelain crowns have metal inside which gives strength and support to the porcelain. This acts as a barrier for light and gives the crown a dull colour. On posterior teeth this will not be noticed, but in the front of the mouth it can occasionally be a problem as the tooth looks duller than the natural teeth.
One disadvantage of a bridge is that the patient should wait three months before placement as the ‘gum’ shrinks’ after a tooth is extracted. If the bridge was fitted early a gap would appear underneath the pontic (the false tooth). At the back of the mouth this may not be a problem, at the front of the mouth however this may appear as a black line along the gum.
Zirconia bridge is high quality, stronger, durable, natural looking and visually appealing as compared to other types of bridges. It is often preferred to metal ceramic bridges in that it causes less tooth sensitivity. Since Zirconia is made from zirconium oxide there is no base metal, and the black lines at the edge of the gum line are eliminated.