Porcelain Inlays & Onlays

What Are Porcelain Inlays and Onlays?

Porcelain inlays and onlays are a type of indirect dental restoration — meaning they are custom-fabricated in a dental laboratory rather than built up directly in the mouth. They are designed to restore teeth that have moderate damage, decay, or fractures that are too extensive for a simple filling but do not require the full coverage of a dental crown. In restorative dentistry, they occupy an important middle ground that allows for a more conservative approach to preserving your natural tooth structure.

At Orion Dental, we offer porcelain inlays and onlays at our Scarborough and Milton locations. Dr. Fahimay Naqvi and our team use these restorations when they can preserve more of your natural tooth compared to a full crown, while still providing the durability and strength that a direct filling may not achieve for larger areas of damage.

Inlays vs. Onlays: What Is the Difference?

Although inlays and onlays are often discussed together, they differ in the amount of tooth surface they cover:

• Inlay: An inlay is a restoration that fits within the cusps of a tooth — the raised points on the biting surface. Think of it as a custom-made filling that sits inside the contours of the tooth. Inlays are typically used when the damage or decay is confined to the centre of the tooth and does not extend over the cusps.
• Onlay: An onlay covers a larger area, extending over one or more cusps. It is sometimes referred to as a "partial crown" because it covers a significant portion of the tooth while still preserving more natural tooth structure than a full crown would. Onlays are used when the damage extends beyond the centre of the tooth to include one or more cusps.

Your dentist will determine whether an inlay or onlay is appropriate based on the extent of the damage, the structural integrity of the remaining tooth, and the forces the tooth will need to withstand during chewing.

Inlays and Onlays vs. Fillings vs. Crowns

Choosing the right restoration depends on how much tooth structure remains and how much support the tooth needs. Here is a general comparison:

• Direct fillings (such as tooth-coloured composite fillings) are placed in a single visit and are suitable for small to moderate cavities. They work well when there is plenty of healthy tooth structure remaining to support the filling.
• Inlays are used when the area of decay or damage is larger than what a direct filling can reliably restore, but the cusps of the tooth are still intact. Because they are made in a laboratory, they offer a precise fit and greater strength for larger restorations.
• Onlays are appropriate when the damage extends over one or more cusps. They provide coverage and strength for a larger area while still preserving more of the natural tooth than a crown.
• Crowns cover the entire visible portion of the tooth. They are recommended when the tooth has extensive damage, after a root canal, or when the remaining tooth structure is not strong enough to support an inlay or onlay.

The goal is always to choose the least invasive restoration that will adequately protect and restore the tooth. Inlays and onlays allow the dentist to remove only the damaged portion of the tooth and preserve as much healthy enamel and dentin as possible.

Why Is Porcelain Used for Inlays and Onlays?

Inlays and onlays can be made from several materials, including gold, composite resin, and porcelain (also called ceramic). Porcelain is a popular choice for several reasons:

• Aesthetics: Porcelain can be closely matched to the natural colour and translucency of your teeth. This makes porcelain inlays and onlays virtually indistinguishable from the surrounding tooth structure, which is particularly important for teeth that are visible when you smile or speak.
• Durability: Porcelain is a hard, wear-resistant material that can withstand the forces of chewing over many years. It is less likely to wear down opposing teeth compared to some other materials.
• Biocompatibility: Porcelain is well-tolerated by oral tissues. It does not cause allergic reactions and does not corrode or release metallic ions into the mouth.
• Stain resistance: Porcelain resists staining from coffee, tea, wine, and other common substances, helping the restoration maintain its appearance over time.
• Stability: Unlike direct fillings, which can expand and contract with temperature changes, porcelain is dimensionally stable, meaning it maintains its shape and fit over time.

What Are the Advantages of Inlays and Onlays?

How Are Porcelain Inlays and Onlays Placed?

The process for receiving a porcelain inlay or onlay typically involves two appointments at our Scarborough or Milton office.

How Do You Care for Inlays and Onlays?

Porcelain inlays and onlays do not require special care beyond good daily oral hygiene. To maintain your restoration and the health of the underlying tooth:

• Brush twice daily with a soft-bristled toothbrush and fluoride toothpaste
• Floss daily, paying attention to the margins where the restoration meets the natural tooth
• Attend regular dental checkups and professional cleanings so your dentist can monitor the restoration
• Avoid biting on very hard objects such as ice, hard candy, or pen caps, which could chip the porcelain
• If you grind or clench your teeth at night, discuss a night guard with your dentist to protect your restorations

How Long Do Porcelain Inlays and Onlays Last?

Porcelain is a hard-wearing restorative material, and with proper care an inlay or onlay can last many years — while offering the advantage of a tooth-coloured appearance. How long any individual restoration lasts varies from person to person. Factors that influence it include the location of the tooth, the forces it experiences during chewing, whether the patient grinds their teeth, and the quality of daily oral hygiene.

During your regular dental appointments, your dentist will examine the restoration for any signs of wear, chipping, or changes at the margins. Early detection of any issues allows for timely repair or replacement, which helps protect the underlying tooth.

When Might an Inlay or Onlay Be Recommended?

Your dentist may recommend a porcelain inlay or onlay in situations such as:

• A cavity that is too large for a direct filling to reliably restore
• A tooth with an old, large filling that needs to be replaced
• A cracked or fractured tooth where the damage does not warrant a full crown
• A tooth with moderate structural damage that still has healthy cusps (inlay) or where one or more cusps need coverage (onlay)
• Situations where preserving the maximum amount of natural tooth structure is a priority

Porcelain Inlays and Onlays at Orion Dental

At Orion Dental, we believe in providing conservative, evidence-based restorative care. When a porcelain inlay or onlay is the appropriate treatment, it allows us to restore your tooth with precision while preserving as much of your natural tooth structure as possible. Dr. Fahimay Naqvi and our team will thoroughly evaluate your tooth, discuss your options, and help you make an informed decision about your care.

To learn more about porcelain inlays and onlays or to schedule an evaluation, book an appointment online or contact our Scarborough office at 416-291-0306 or our Milton office at 905-636-9770.