Crown vs Onlay - What’s the difference, and which is best for you"?
Deciding on the best treatment option to fix a broken or damaged tooth can be daunting. You may find yourself torn between two common solutions: dental crowns and onlays. But which one is best for you? We're here to help you navigate this decision with clarity and confidence.
What is a Dental Crown?
Think of a dental crown as a protective helmet for your tooth. It's a custom-made cover that covers your entire tooth. Dentists have traditionally used crowns for teeth that are severely damaged, discoloured, or misshapen. It's like a fresh coat of paint and a protective barrier all in one – improving how your tooth looks and giving it extra strength.
A crown protects a tooth by holding it all together from all directions. Crowns rely on this wrap to stay on, alongside the help of dental cement.
Crowns before and after
Images from Dr Zaeem Jafri from Innovadent Dental Clinic
Broken down teeth with large fillings that require crowns
Teeth prepared for crowns and veneer
Crowns and veneer fitted
What is an Onlay?
On the other hand, a dental onlay is more like a partial cover for your tooth. Due to advances in dental bonding technology, onlays are becoming more reliable.
Rather than wrap around the entire tooth, an onlay rebuilds any broken-down area of a tooth and covers the biting section. Onlays can vary in design as they are dictated by how broken down the tooth is and how your dentist wants to restore it.
Onlays provide the same amount of protection for your teeth compared to crowns, but require much less drilling of your tooth structure which makes them more preservative.
Since onlays don’t wrap around your tooth, they rely on dental ‘bond’ (glue) to stay in place.
Onlays before and after
Images from Dr Zaeem Jafri from Innovadent Dental Clinic
Teeth with large fillings and cracks
Prepared for an onlay
Onlays fitted
Crown vs Onlay: What's the Difference?
The roles of crowns and onlays are largely the same, to rebuild your broken tooth and prevent them from cracking or breaking in the future. Here are the main differences between crowns and onlays:
Coverage: Crowns cover your entire tooth, much like a helmet, making them more destructive to your natural tooth. Onlays, however, only cover the part of your tooth that's damaged.
Retention: Crowns rely on mechanical retention (wrapping around your tooth) and cement, whereas onlays are bonded (glued) in place.
Invasiveness: Onlays are a lot less destructive of your natural teeth, so if your tooth is alive, it is less likely to need a root canal filling after treatment
Difficulty: Onlays are a more modern technique, so those with less experience in preparing and bonding onlays may not be as comfortable doing them
It’s worth noting that you can’t place onlays on your front teeth. Onlay can only be placed on molars and premolars.
If you want to change the shape or look of your front teeth without being too invasive you would need to consider porcelain veneers (which are the closest thing to an onlay for your front teeth) or composite bonding.
Crown vs Onlay: Which is Right for You?
Choosing a dental crown or an onlay depends on your unique situation and your dentist's advice.
With the advancements in dental care, onlays are often the first choice because they are less invasive and keep more of your natural tooth intact. Onlays are like the superheroes of modern dentistry, stepping in to save the day (and your tooth!).
But sometimes, a dental crown might be the better option. For example:
If your tooth has already been prepared for a crown in the past
If your dentist is trying to change the size and shape of your tooth
If you are trying to cover up a darkened tooth
Your tooth is not suitable for bonding
Your dentist is not trained to prepare and fit onlays to a high standard
Always remember that your unique clinical situation will guide the best treatment choice.
When thinking about a crown vs an onlay, chat with your dentist. They can provide expert advice based on your dental health history and current needs.
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Understanding the difference between dental crowns and onlays is your first step towards a healthier, brighter smile. So, chat with your dentist and be confident that you're making the right decision for your dental health.