Inlays vs. Onlays: Which is Right for You?

Inlays are custom-made fillings that are created outside of the mouth and then bonded to the damaged area of a tooth. They are typically used for cavities that are located in the grooves of the back teeth, particularly the molars, where traditional fillings may not suffice. Inlays are designed to fit snugly within the contours of the tooth, providing a precise and durable restoration.
Onlays, on the other hand, are similar but cover a larger area of the tooth. They not only fill the cavity but also extend over the cusps (the pointed parts) of the tooth. This makes onlays a suitable option for more extensive damage, often used when a tooth is too compromised for an inlay but does not require a full crown.

The choice between inlays and onlays largely depends on the extent of tooth damage and the specific location of the decay.

Inlays are indicated when:

• A tooth has moderate decay that does not affect the cusps.
• A tooth requires reinforcement but retains sufficient healthy structure.
• A more conservative restoration is desired to preserve tooth structure.

Onlays are indicated when:

• A tooth has extensive decay that compromises the cusps.
• The tooth structure is weak and needs additional support.
• There is a need to restore the shape and function of the tooth more comprehensively.

One of the critical differences between inlays and onlays lies in their coverage and the extent to which they preserve tooth structure.
 

Tooth Coverage:
Inlays cover only the internal surfaces of the tooth, fitting neatly within the cusps. This limited coverage makes them ideal for minor to moderate restorations, allowing for a more conservative approach.
Onlays, in contrast, cover a more extensive area, including the cusps, providing greater support and protection. While this may seem more invasive, it can be essential for teeth that have significant damage.
 

Tooth Structure Preservation:
Inlays often preserve more of the natural tooth structure because they require less alteration to the tooth. The procedure involves removing only the decayed portion, allowing the tooth to maintain its strength and integrity.
Onlays require more tooth structure to be removed to accommodate the larger restoration. However, they are still considered a conservative option compared to full crowns, as they can often save more tooth structure than traditional methods would.

Both inlays and onlays can be made from various materials, including porcelain, composite resin, and gold.

• Porcelain inlays and onlays are popular for their aesthetic appeal, as they can be color-matched to the natural tooth. They provide a strong bond and are resistant to staining.
• Composite resin is another option that offers good aesthetics and is often used for smaller restorations. However, it may not be as durable as porcelain or gold for larger restorations.
• Gold inlays and onlays are incredibly durable and are often chosen for their strength, particularly in posterior teeth that endure significant chewing forces. However, their metallic appearance may not be suitable for all patients.

In terms of durability, both inlays and onlays can last many years with proper care. Typically, porcelain inlays and onlays can last between 10 to 15 years, while gold can last even longer. The specific lifespan will depend on factors such as oral hygiene, the location of the restoration, and the patient's dietary habits.

While the choice between inlays and onlays often hinges on clinical factors, cost can also play a significant role. Generally, inlays may be less expensive than onlays due to the lesser amount of material used and the reduced complexity of the procedure. However, insurance coverage may vary, and patients should consult their dental insurance providers to understand their benefits regarding these restorations.

For inlays and onlays, relevant ADA Dental Codes include:

D2510: Inlay, metallic, one surface

D2511: Inlay, metallic, two surfaces

D2512: Inlay, metallic, three surfaces

D2520: Onlay, metallic, one surface

D2521: Onlay, metallic, two surfaces

D2522: Onlay, metallic, three surfaces

Choosing between inlays and onlays involves careful consideration of the extent of tooth damage, the need for coverage, and the desire to preserve natural tooth structure. Inlays are ideal for minor to moderate damage, while onlays provide the necessary support for more extensive decay. Consulting with a dental professional can help determine the most appropriate option based on individual circumstances.
For those exploring affordable dental solutions, Dr. BestPrice offers a dental auction site that connects patients with budget-friendly dental care options. Whether seeking dental insurance or looking for a low-cost dentist near you, navigating the world of dental treatments can lead to significant savings.