What is an Onlay?

An onlay is a partial filling crown that covers the biting surface of the tooth. It may also replace one or more sides of the tooth.

Why do I need an Onlay?

We often recommend an onlay as a treatment option instead of a crown especially if there is not a lot of teeth left.

There are several reasons why an onlay may be an option for a repairing a tooth:

  • If your tooth is heavily broken down, has been root filled or has large existing fillings in place then an onlay can be a good option to help restore the tooth to its natural shape. It can also reduce the chance of a future breakdown of the tooth.
  • If your teeth are worn, broken or have old discoloured fillings, onlays can be used to improve the shape and appearance of your teeth.
  • An onlay can be less intrusive than a crown, as less of your tooth has to be cut back and your tooth is left stronger in the long term.

 

What is an onlay made of?

Onlays can be either made of tooth-coloured ceramic material (such as e.max), tooth coloured composite resin (like a white filling) or of metal.

Your dentist will discuss with you which material choices are available and the advantages of each in your particular case.

All of our onlays are custom made for each individual case by a highly skilled dental technician to ensure an excellent fit and appearance.

Usually, we will need an up to date X-ray of your tooth/teeth to check that the roots are healthy and the foundations strong before commencing on the process of preparing your tooth for an onlay.

 First appointment: Onlay Preparation

Your dentist will carefully shape your tooth to allow space for the crown. This is usually done under local anesthetic.

We will take impressions of your teeth, choose a shade for your crown to match your existing teeth and finally provide you with a temporary crown to cover the prepared tooth.

 

 Second appointment: Onlay Fit

Roughly 2 weeks later, your temporary only will be removed and replaced with your new only.

Your dentist will ensure a good fit and appearance of the new only, then cement or bond it into place using the appropriate material for your only to ensure it lasts well.

We will also give you advice on how best to care for your onlay over the years to come.

 

 How long will my onlay last?

Onlays typically last around 10-15 years.

There are a wide variety of factors that influence this, including:

  • the strength of the underlying tooth
  • the health of the nerve within the tooth
  • the position of the tooth within the mouth
  • how much stress and strain a particular onlay is put under
  • how well the onlay is looked after.