Understanding Dental Inlays and Onlays: What Makes Them Different from Fillings?

Young woman having filling put in clinic

Today, we’re here to shed some light on dental inlays and onlays – two options that go beyond traditional fillings when it comes to restoring teeth.

What Are Dental Inlays and Onlays?

Dental inlays and onlays are custom-made restorations used to repair teeth that have been damaged by decay or other forms of damage. They are crafted from various materials including porcelain, composite resin, or gold. Inlays and onlays are designed to fit precisely into the prepared cavity of a tooth.

How Are They Different from Fillings?

The main difference between dental inlays/onlays and traditional fillings lies in their size and placement. While fillings are directly placed into the cavity of a tooth, inlays and onlays are fabricated outside of the mouth and then bonded onto the tooth surface.

Inlays: Inlays are used to fill cavities that are confined within the cusps (raised points) of a tooth. They provide a more conservative option compared to traditional fillings because they require less removal of healthy tooth structure.

Onlays: Onlays, also known as partial crowns, are used to repair teeth with more extensive damage that extends beyond the cusps. They cover a larger portion of the tooth’s surface, including one or more cusps, and are suitable for restoring strength and function to the tooth.

Types of fillings illustration. Dental inlay, dental onlay, and dental crowns.

When Are They Helpful?

Dental inlays and onlays are recommended in situations where traditional fillings may not provide adequate support or durability. Here are some scenarios where they might be helpful:

  1. Large Cavities: When a cavity is too large for a filling but not extensive enough to require a full crown, an inlay or onlay can provide a suitable solution.
  2. Fractured Teeth: Teeth that are fractured or have cuspal damage can benefit from the reinforcement provided by an onlay, restoring both appearance and function.
  3. Cosmetic Concerns: Inlays and onlays can be made from tooth-coloured materials, offering a more aesthetically pleasing option for restoring visible teeth at the front of the mouth.
  4. Preservation of Healthy Tooth Structure: Inlays and onlays allow for the preservation of more healthy tooth structure compared to other treatments such as crowns, making them a conservative option for dental restoration.


At Honest Tooth Dental Care, we understand that each patient’s dental needs are unique. That’s why we offer a range of options, including dental inlays and onlays, to suit different situations and preferences. If you’re experiencing tooth decay or damage, don’t hesitate to schedule an appointment with us. Our experienced team will assess your condition and recommend the most suitable treatment to restore your smile and oral health.