Porcelain Crowns are recommended to replace moderate to large restorations (fillings). A crown should be recommended before the tooth surrounding the restoration breaks, in order to ensure there is enough strength in the remaining tooth to support the crown. A crown acts as a thimble, fitting perfectly over the whole tooth, preventing it splitting or breaking in the future.
There are a number of different types of crowns.
- Porcelain fused to metal crowns are where the inner core of the crown is constructed of a gold alloy material to which porcelain is fused. Aside from the full gold crowns (where the tooth appears as yellow gold in colour) this is the strongest crown a dental technician can make. Although a great cosmetic result can be achieved, due to the inner metal core, sometimes the colour can’t be matched perfectly.
- Full ceramic crowns, where the entire crown is made out of porcelain and ceramic. These crowns are fantastic cosmetically, but can lack in strength compared to porcelain fused to metal crowns. These are only suitable in select cases, such as front teeth that don’t take much load or patients who have a favourable occlusion (how they bite together)
Usually two appointments are required for a crown, provided the existing restoration is sound. At the first appointment the dentist will trim back and shape the tooth ensuring there is enough room for the crown to fit on top of it. A mould is then taken of the tooth and how the patient bites. The mould is then sent off to a dental technician who constructs the crown. Two to three weeks later, the patient returns to the dentist. After checking the colour and fit, the crown is then permanently cemented in place.