Why would I need a crown or onlay?
Crowns and onlays become the treatment option of choice when a cavity is large and the underlying tooth is weak. They are made of very high strength materials, usually tooth coloured ceramics or metallic materials such as gold, and are very good at holding a natural tooth together and very resistant to breaking.
What does the treatment involve?
In order to create space for a crown or onlay, your tooth is re-shaped by the dentist, and then a mould or a digital scan of the tooth is taken. This is then sent to a professional called a dental lab technician who will custom make the crown/onlay for you in their laboratory. It is then cemented onto your tooth by the dentist on another day.
What is the difference between a crown and onlay?
The difference between a crown and an onlay is that a crown covers the entirety of the natural tooth, whereas an onlay covers just the chewing surface of the tooth and only part of the side walls of the tooth. Where possible we prefer to do onlays rather than crowns as less tooth re-shaping is required so the process is kinder to the natural tooth, ultimately meaning that the tooth will survive for longer. There are many scenarios where an onlay is not possible and a crown is needed however. Your dentist will advise you on your particular situation.