When Is a Dental Onlay Better Than a Crown?

In dentistry, an onlay and crown are two types of tooth restoration treatments(among a few others) that are implemented on a serious decay, a cracked tooth, discolouration of the tooth, among other tooth-related scenarios.


However, we often seem to get confused between a dental onlay and a crown and the respective oral health problems where they can be used. To get a clear picture of the best dental restorative treatment, we will be conversing on onlay vs crown today.


What is an Onlay?


As the term implies, it is a covering placed ‘on’ or at the top of the problematic tooth. It involves a repair of your damaged or decayed tooth and is preferred when a cavity is too severe for a regular filling.


When you experience symptoms of tooth trouble such as pain, or you may feel that you have a cavity, a dental onlay is the better option. Unlike the crown treatment, onlay is a less invasive method and does not involve the removal of a healthy tooth structure. Therefore, a dentist may opt or suggest you take up an onlay over a crown.


At the same time, there are a few circumstances where a crown is required to an extent:

  • To hold on to a dental bridge in place.
  • To cover a dental implant.
  • To restore a tooth from nerve damage which sometimes leads to the need for a root canal.
  • To protect a structurally weak tooth from fracturing, breaking or cracking.
  • To eliminate tooth discolouration for a bright and white result.
  • To replace a tooth that’s been knocked out.


The procedure of crown is vital in situations where the patient requires a whole-scale replacement. It involves the placement of a cap after removing the existing tooth decay. However, in some cases, onlays can function efficiently just like crowns do; therefore, your dentist may go with the former over the crown in order to protect the structure of your teeth.


Types of Onlays


If you choose this procedure, your dentist will also explain to you the various kinds of onlays that you can select from. Just like a crown, onlays can be made out of,


  • Resin materials
  • Gold
  • Porcelain


Porcelain is usually preferred since the colour resembles your natural teeth and is often used for front teeth. Gold or resin is an ideal choice for your molars and premolars due to their strength and durability. At this stage, your dentist can better explain the different aspects of the materials to keep in mind before you make your choice.


When and how is a dental onlay better than a crown?


Circumstances where an onlay should be considered over a crown,


  • When a tooth requires a repair rather than replacement.
  • You only require fixing one of your cusps. A crown should be considered if you need a fix for several cusps.
  • If there is less decay to remove which will preserve the tooth’s original structure and curvature. 
  • If you still have enough structural stability to support the restoration, then dental onlay is a better choice.


We hope that this article can help you with all your doubts about choosing between an onlay and crown. If you still feel unsure about the right option, contact Rouse Hill Smiles Dental Care for consultations and affordable onlay dental costs.