Dental Crowns, Inlays and Onlays

Many people are familiar with the idea of a dental crown or cap, but now many people know enough about inlays and onlays and how they can help your smile. In this post, we’ll discuss these three types of dental restoration treatments so that you might know what solutions will help with weakened, damaged or decayed teeth.

Ceramic molar onlay on red gypsum model on isolated background

What are dental crowns? 

A dental crown is a tooth-shaped cap that is placed over a damaged, decayed or weakened tooth to restore shape, size, strength, function and appearance. People get crowns in order to protect the teeth from breaking or to hold together parts of a cracked tooth, to cover a tooth with a large filling, to hold a dental bridge in place, to restore a severely misshaped or discoloured tooth, to cover a dental implant or to strengthen a tooth after root canal treatment. Dental caps can be made of metal, porcelain-fused-to-metal, porcelain or resin.


Inlays and onlays 

An inlay is similar to a filling in that a solid substance (such as gold, porcelain or resin) is fitted to a cavity in a tooth and cemented in place. Inlays are bonded inside the cusp tips of the tooth to fuse the damaged areas. Usually, this method is used over direct restoration in cases when the decay or fracture is so extensive that an inlay is the only way to maintain the structural integrity of the restored tooth.

An onlay is also bonded to the damaged area of the tooth, but it is a more substantial reconstruction that involves replacing the tooth cusp by covering, or onlaying, the area where the missing cusp would be. This provides a choice for conserving the tooth structure, rather than totally eliminating the cusps and perimeter walls for crown restorations. Onlays and inlays provide a good alternative where there is not enough damage to the tooth to merit an entire crown, but where there is still sufficient damage to warrant restorative treatment.

Traditionally, onlays and inlays have been made of strong gold, but now porcelain has gained popularity due to its natural-looking colour and strength.


What is involved in inlay and onlay procedures? 

For these procedures, you’ll need two appointments. The first visit involves replacing damaged filling or removing decay from the tooth to prepare it for the inlay or onlay. The dentist will take an impression of the tooth to ensure a proper fit and bite, which will be sent to the lab for fabrication. Then we’ll apply a temporary restoration on the tooth.

During the next appointment, we’ll remove the temporary restoration and test the inlay or onlay to make sure it fits properly. If we’re all satisfied with the fit, we’ll bond the inlay or onlay to the tooth and give it a polish for a smooth finish.


Whether you think you need a tooth filling, dental onlay or dental crown, one thing’s for sure: Ignoring your dental problem will put you in a gray area with your dental health. Regardless of which restoration you end up with, your teeth will thank you. Talk to our professional dentists at Randwick Dental Clinic in Sydney about the dental restorations.