Do I need a filling, a ceramic onlay or a crown?

Imagine two back teeth with fillings of about the same size. On one tooth, the walls around the filling are sound. On the other, one of the raised points you chew on has cracked. The teeth may need different treatment, even though their fillings look alike.

• A direct filling may be enough when the remaining walls can support it. We shape the filling in the mouth.
• A ceramic inlay fits between the raised points, or cusps. An onlay also covers one or more cusps that need protection.
• A full crown covers the chewing surface and wraps around the tooth. We may consider it when several walls have lost support and a partial restoration would leave too much of the tooth at risk.

At your visit, we can show you the area on a photograph or scan and explain which parts of your own tooth each option would preserve.

What is the difference between an inlay and an onlay?

An inlay replaces the missing area between the cusps on the chewing surface of a tooth.

An onlay also covers one or more weakened cusps. The area covered by the restoration therefore depends on the support the tooth requires. These restorations are made outside the mouth and then bonded to the tooth.

The terminology can initially sound technical. During an examination, showing the difference on an image of the tooth can make it easier to understand which area needs coverage and why.

How is it different from a regular filling?

A direct composite filling is shaped in the mouth. An inlay or onlay is produced from an impression or digital scan and then fitted to the tooth.

This does not mean a ceramic restoration is better in every situation. A composite filling may be sufficient for a small or appropriately sized area of lost tooth structure.

When there is a large cavity, weakened walls or a need to protect part of the chewing surface, we discuss other options. The decision is not based on the size of the existing filling alone.

When might we consider them?

Inlays and onlays may be considered when an old, large filling needs replacing, when a cusp has fractured or when a substantial amount of tissue is lost after decay is removed.

They may also be considered for root-filled teeth. Root canal treatment alone, however, does not dictate a particular type of restoration.

The remaining walls, the presence of cracks and the bite relationship are important. We also assess whether the bonding area can be isolated appropriately.

Does every heavily filled tooth need a crown?

The choice between a full crown and a partial restoration depends on the remaining tooth structure.

In a suitable tooth, an onlay can cover specific areas without surrounding the entire tooth. If the remaining structure is too weak to preserve or other clinical concerns are present, a more extensive treatment may be required.

What does treatment involve?

We first assess the existing filling, decay and remaining tissues. When treatment begins, the necessary cleaning and preparation are carried out.

An impression or digital scan is taken. The restoration is then produced using the selected method. A temporary filling may be required in some cases.

At the fitting appointment, we check the margins, contact with neighbouring teeth and the bite before completing the bonding procedure. The number of appointments depends on the system used and the condition of the tooth.

Are ceramic inlays and onlays durable?

Durability is influenced by the remaining tooth structure, restoration design, ceramic material, bonding conditions, bite forces and oral care. With appropriate case selection and regular reviews, they can function for many years, but it is not appropriate to promise one standard lifespan for every restoration.

Teeth grinding, biting hard objects and inadequate oral hygiene may increase the risk of fracture or deterioration at the margins. Reviews assess the restoration as well as the tooth and surrounding tissues.

WhatsApp messages are read by the Dentince team. Please do not send health reports or identity documents. Privacy notice