Overlays, Inlays and Onlays
Overlays and onlays are a superior alternative to traditional dental crowns. What makes them better than traditional crowns is that they don’t require the same amount of tooth structure be removed - only the damaged parts. When done properly overlays better seal the tooth to protect the nerve within the tooth from bacterial infection. Compared to traditional crowns, overlays require roughly 50% less tooth structure removal.
Traditional crowns often have “microleakage” underneath them which over the years can deteriorate the tooth (like wood rotting). In order to prevent that from happening we perform an additional step called “immediate dentin sealing” to preserve the tooth (similar to sealing wood) that preserves the tooth underneath the ceramic. This means more of the original tooth is left, and a tooth restored with an overlay has a roughly 10x lower risk of needing a root canal in the months and years after it’s placed. This saves you money and teeth in the long run by stopping the “tooth cycle of death.” Additionally, the gums are typically healthier and get less inflamed when compared with traditional dental crowns.
The one downside to this 2 appointment procedure is that it takes slightly longer to perform than a traditional crown. However, the restorations are expected to last longer and conserve more of your natural tooth. Should it ever need to be replaced the tooth will be much easier to repair - unlike traditional crowns - which are much more likely to result in root canals, and ultimately tooth loss - requiring more costly implants when they need to be replaced.
We take pride in our craftsmanship, and invite you to view the treatment photos below which show each step of the process.
Traditional Crown/Cap
Inlay
Overlay
Onlay
Before
After
Before
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Leaky restorations are commonplace if a restoration isn’t placed carefully, and can lead to rapid deterioration of tooth structure as bacteria, acid, and miscellaneous debris will inevitably become trapped underneath the restoration against the tooth.
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Cracks in teeth occur most often in large fillings because the tooth flexes about the width of a hair when chewing. The bigger the filling the more the tooth may flex if the filling is not bonded.
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Signs of a cracked restoration or cracked tooth can vary wildly. Both can cause a 'zinging' feeling when you bite down, or you might not notice anything at all. Cracks can be difficult to see to the naked eye, which is why your dentist should be wearing high magnification loupes to exam your teeth.
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The blue background in many of the photos is what's known as a rubber dam. It's a sheet of rubber that keeps the teeth clean and dry from contamination (saliva, blood, etc.). Not all dentists use them because they take more time to place well - it's an art in itself. A rubber dam is probably the most important tool for dentists performing adhesive dentistry, without them this restoration would not be expected to last.
Crack Removal
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Once cracks get wide enough to allow bacteria to squeeze inside of them, they can start to subtly cause cavities right under an old restoration. These cavities are harder for your dentist to spot and can lead to an increased amount of tooth structure lost before its detected.
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Staining under an old restoration occurs either due to corrosion of an old 'silver' filling, or due to a leaky filling allowing bacteria and pigments to discolor the tooth from the inside.
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Aerospace engineers were some of the first scientists to figure out how to repair cracks. Dentists are catching on by applying those engineering principles to teeth. Ideally, cracks should be completely removed to their endpoint to prevent them from continuing down the root which can lead to catastrophic results.
Sealed
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This technique - known as immediate dentin sealing, or IDS - protects the inner layer of the tooth from contamination. It's a time consuming procedure that few dentists do because it requires many extra steps.
Ceramic Overlays
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Bonded ceramic restorations seal 360 degrees around the tooth. This means that staining won't occur, and cavities won't form underneath them. The nerve in your tooth will never guess it's there.
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Bonded ceramic overlays protect the tooth underneath and are designed to fail (fall off) before the tooth underneath suffers damage. Traditional crowns are like a hard cast for your tooth that never comes off - usually until it's too late. Traditional crowns are like 1960's automobiles without crumple zones - something we used to think was a good thing. However, after discovering a lot more injuries occurred in more rigidly built cars when accidents occurred, engineers decided it was better to protect the passenger (in this analogy, your tooth) than it was to have the car look pretty after a crash. Overlays are like a crumple zone on your car - but for your tooth.
Before
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Cracks in teeth occur most often in large fillings because the tooth flexes about the width of a hair, sometimes more or sometimes less, when chewing. The bigger the filling the more the tooth may flex if the filling is not bonded. Cracks quickly provide an avenue for bacteria to enter the tooth.
-
Signs of a cracked restoration or cracked tooth can vary wildly. A cracked tooth can cause a 'zinging' sensation when you bite down, or you might not notice anything at all. Cracks can be difficult to see to the naked eye, which is why your dentist should be wearing high magnification loupes to examine your teeth.
-
The blue background in many of the photos is what's known as a rubber dam. It's a sheet of rubber that keeps the teeth clean and dry from contamination (saliva, blood, etc.). Not all dentists use them because they take more time to place well - it's an art in itself. A rubber dam is probably the most important tool for dentists performing adhesive dentistry, without them this restoration would not be expected to last.
Deep Crack Removal
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Once cracks get wide enough to allow bacteria to squeeze inside of them, they can start to subtly cause cavities right under an old restoration. These cavities are harder for your dentist to spot and can lead to an increased amount of tooth structure lost before its detected.
-
Staining under an old restoration occurs either due to corrosion of an old 'silver' filling, or due to a leaky filling allowing bacteria and pigments to discolor the tooth from the inside.
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If you noticed the dark pink staining where the crack is on this tooth - good eye. That's a special kind of dye dentists use to stain bacteria that cause cavities, allowing us to visualize where infected tooth structure exists. This is an extra step we will perform if necessary, and it isn't common in the modern dental office because it takes more time.
Sealed
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This technique - known as immediate dentin sealing, or IDS - protects the inner layer of the tooth from contamination. It's a time consuming procedure that few dentists do because it requires many extra steps.
-
Ribbond is a specially woven ultra-high molecular weight polyethylene fiber that is bonded to the tooth underneath a restoration. Bonding this too the tooth creates extra protected region of the tooth underneath the sealed layer. This enhances the bond strength of the tooth to the sealed layer which doubles to preserve the health of the nerve and allow natural flexing of the tooth without debonding of the restoration or fracturing of the tooth.
Ceramic Overlay
-
Bonded ceramic restorations seal 360 degrees around the tooth. This means that staining won't occur, and cavities won't form underneath them. The nerve in your tooth will never guess it's there.
-
Bonded ceramic overlays protect the tooth underneath and are designed to fail (fall off) before the tooth underneath suffers damage. Traditional crowns are like a hard cast for your tooth that never comes off - usually until it's too late. Traditional crowns are like 1960's automobiles without crumple zones - something we used to think was a good thing. However, after discovering a lot more injuries occurred in more rigidly built cars when accidents occurred, engineers decided it was better to protect the passenger (in this analogy, your tooth) than it was to have the car look pretty after a crash. Overlays are like a crumple zone on your car - but for your tooth.
Before
-
Cracks in teeth occur most often in large fillings because the tooth flexes about the width of a hair, sometimes more or sometimes less, when chewing. The bigger the filling the more the tooth may flex if the filling is not bonded. Cracks quickly provide an avenue for bacteria to enter the tooth.
-
The blue background in many of the photos is what's known as a rubber dam. It's a sheet of rubber that keeps the teeth clean and dry from contamination (saliva, blood, etc.). Not all dentists use them because they take more time to place well - it's an art in itself. A rubber dam is probably the most important tool for dentists performing adhesive dentistry, without them this restoration would not be expected to last.
Onlay Preparation (left)
Overlay Preparation (right)
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If there is enough healthy tooth left, we may be able to preserve more tooth structure by placing an onlay instead of an overlay.
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Once cracks get wide enough to allow bacteria to squeeze inside of them, they can start to subtly cause cavities right under an old restoration. These cavities are harder for your dentist to spot and can lead to an increased amount of tooth structure lost before its detected.
-
Staining under an old restoration occurs either due to corrosion of an old 'silver' filling, or due to a leaky filling allowing bacteria and pigments to discolor the tooth from the inside.
Sealed Preparations
-
This technique - known as immediate dentin sealing, or IDS - protects the inner layer of the tooth from contamination. It's a time consuming procedure that few dentists do because it requires many extra steps.
-
Ribbond is a specially woven ultra-high molecular weight polyethylene fiber that is bonded to the tooth underneath a restoration. Bonding this to the tooth creates extra protected region of the tooth underneath the sealed layer. This enhances the bond strength of the tooth to the sealed layer which doubles to preserve the health of the nerve and allow natural flexing of the tooth without debonding of the restoration or fracturing of the tooth.
Ceramic Onlay (left)
Ceramic Overlay (right)
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Bonded ceramic overlay and onlay restorations seal 360 degrees around the tooth. This means that staining won't occur, and cavities won't form underneath them. The nerve in your tooth will never guess it's there.
-
Bonded ceramic overlays protect the tooth underneath and are designed to fail (fall off) before the tooth underneath suffers damage. Traditional crowns are like a hard cast for your tooth that never comes off - usually until it's too late. Traditional crowns are like 1960's automobiles without crumple zones - something we used to think was a good thing. However, after discovering a lot more injuries occurred in more rigidly built cars when accidents occurred, engineers decided it was better to protect the passenger (in this analogy, your tooth) than it was to have the car look pretty after a crash. Overlays are like a crumple zone on your car - but for your tooth.
Before
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Fractured cusps can occur when a crack runs diagonally through the tooth from the top towards the bottom. Cracks can take years to develop, or happen in seconds due to sports, accidents, or chewing on something very hard (eg: ice). Either way, the cracks can lead to a piece of the tooth fracturing off.
Isolation
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Dentin is the inner part of a tooth. Exposed dentin is never a good thing. Dentin is softer, more porous, and more susceptible to acid and abrasion than enamel. Losing enamel and chewing is like losing the treads on a car tire and going for a road trip.
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Staining under an old restoration occurs either due to corrosion of an old 'silver' filling, or due to a leaky tooth colored filling allowing bacteria and pigments to discolor the tooth from the inside. Staining can also be harmless surface staining which occurs commonly on molars and premolars (back teeth) where deep grooves or pits collect staining from foods.
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The blue background in all the photos is what's known as a rubber dam. It's a sheet of rubber that keeps the teeth clean and dry from contamination (saliva, blood, etc.). Not all dentists use them because they take more time to place well. These are vitally important tools for dentists performing adhesive dentistry, without them this restoration would not be expected to last.
Sealed
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This case required deep margin elevation be performed. DME is an advanced technique that allows teeth to be restored without leakage occurring under the bonded onlay restoration.
-
This technique - known as immediate dentin sealing, or IDS - protects the inner layer of the tooth from contamination. It's a time consuming procedure that few dentists do because it requires many extra steps.
Ceramic Onlay
-
Bonded ceramic restorations seal 360 degrees around the tooth. This means that staining won't occur underneath them, and cavities can't form undetected underneath them. The nerve in your tooth will never guess it's there.
-
Bonded ceramic overlays protect the tooth underneath and are designed to fail (fall off) before the tooth underneath suffers damage. Traditional crowns are like a hard cast for your tooth that never comes off - usually until it's too late. Traditional crowns are like 1960's automobiles without crumple zones - something we used to think was a good thing. However, after discovering a lot more injuries occurred in more rigidly built cars when accidents occurred, engineers decided it was better to protect the passenger (in this analogy, your tooth) than it was to have the car look pretty after a crash. Overlays are like a crumple zone on your car - but for your tooth.
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