Inlays and Onlays vs. Composite Fillings: What’s the Difference?

When a tooth develops decay or damage, restoring it quickly and properly is essential to protecting your long-term oral health. Many patients are familiar with composite (tooth-colored) fillings, but fewer know about inlays and onlays, which can be an excellent option in certain situations.

Understanding the differences between these treatments can help you make a more informed decision about your dental care.

What Are Composite Fillings?

Composite fillings are made from a tooth-colored resin material and are commonly used to treat small to moderate cavities.

Benefits of Composite Fillings:

• Match the natural color of your teeth
• Can usually be completed in a single visit
• Require minimal removal of tooth structure
• More affordable than indirect restorations

Limitations:

• Less durable for larger areas of damage
• Can wear down or stain over time
• May not provide enough strength for teeth under heavy chewing forces

Composite fillings are ideal for smaller cavities or minor repairs, especially in low-stress areas of the mouth.

What Are Inlays and Onlays?

Inlays and onlays are custom-made restorations, typically crafted from porcelain or ceramic, that are bonded to the tooth. They fall between a filling and a crown in terms of strength and coverage.

• Inlay: Fits within the grooves of the tooth, not covering the cusps
• Onlay: Covers one or more cusps of the tooth, offering added protection

Benefits of Inlays and Onlays:

• Extremely strong and long-lasting
• More resistant to wear and staining
• Custom-designed for a precise fit
• Preserve more natural tooth than a full crown
• Restore strength to weakened teeth

Considerations:

• Typically require two visits (unless same-day technology is available)
• Higher upfront cost than composite fillings
• Not necessary for small cavities

Inlays and onlays are often recommended when a tooth has moderate to significant damage but doesn’t require a full crown.

Which Option Is Right for You?

The best choice depends on:

• The size and location of the cavity or damage
• How much natural tooth structure remains
• Your bite and chewing habits
• Long-term durability goals
• Aesthetic preferences

The Goal: Preserve and Protect Your Natural Teeth

At the end of the day, restorative dentistry isn’t just about fixing a cavity—it’s about protecting your tooth for the long term. While composite fillings are a great solution in many cases, inlays and onlays can offer superior strength, longevity, and aesthetics when more support is needed.

A comprehensive dental exam allows your dentist to recommend the option that best supports your oral health, lifestyle, and smile goals.