What is the difference between an inlay, an onlay and a crown?

All these restorations help restore a broken down tooth. A crown is generally used when there is only a small amount of natural tooth left. It effectively envelops all surfaces of the tooth.

Inlays and onlays are very similar in that the tooth requires only a minimal amount of preparation. They are an ideal way to restore a decayed or broken down tooth without removing much tooth substance. They are held in place by special dental adhesives.

As you will see from the diagram above an inlay sits within the tooth whereas an onlay replaces one or more missing walls. Sometimes an onlay also covers over a cusp (the pointed part of a tooth) to provide additional strength.

Why would I need an inlay/onlay?

If you have broken a large filling or have a large amount of decay in a tooth then an inlay may be a suitable option for you.  Research has shown that this type of restoration is usually longer lasting than a simple white filling.

What are inlays and onlays  made from?

They are mostly made from pressed ceramic which is a strong and very natural looking material. Occasionally we still sometimes recommend the use of gold if appearance is not paramount.

How is the tooth prepared?

All decayed or weakened parts of the tooth are removed; the dentist will then take an impression of the prepared tooth. This impression, along with a record of the shade of your tooth will be sent to the dental laboratory where the restoration will be made. A temporary filling will be placed in your tooth to protect it for the two weeks which it takes for the technician to make the new restoration.

Will they be noticeable?

We try our very best to match the shades so that the new restoration is virtually unnoticeable.

How are they fixed to the teeth?

Once the fit and appearance has been checked and approved by you and the bite checked and perfected by the dentist, the inlay or onlay will be cemented in place with a special dental adhesive.

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