Cosmetic Dentistry · Led by Dr. Huong Nguyen (Dr. Rosie) · Last reviewed May 2026
Inlays and Onlays: The Right Restoration
Between Filling and Crown.
When a cavity is too large for a filling but the tooth is too healthy for a crown, the right answer is a porcelain inlay or onlay. Picasso Dental places Emax pressed lithium disilicate inlays and onlays, and full chewing-surface overlays (tabletops), every restoration carrying a 5-year material warranty. Cases are led by Dr. Huong Nguyen (Dr. Rosie), our cosmetic dentist, with iTero digital impressions and lab-pressed porcelain across our six branches.
What's the Difference Between an Inlay, Onlay and Overlay?
All three are partial-coverage porcelain restorations that sit between a filling and a full crown. They differ only in how much of the tooth they cover. Each one is fabricated outside the mouth from pressed Emax porcelain, then bonded in place at a second visit.
Inlay
A restoration that fits inside the cusps of the tooth, like a precision-fit filling. Used when decay or an old filling sits in the central pit of the chewing surface but the surrounding cusp walls are intact. The smallest of the three options.
Onlay
Covers one or more cusps but not the full tooth. Used when one cusp wall has fractured or a cavity has extended over a cusp, but the remaining cusps are still structurally healthy. Partial-coverage, not full-coverage.
Overlay / Tabletop
Covers the entire chewing surface but not the sides of the tooth. The largest of the three partial-coverage options, but still preserves more tooth than a crown. Used when most or all cusps need restoring but the side walls of the tooth remain healthy.
Inlay/Onlay vs Filling vs Crown
The honest comparison. The right choice depends on how much tooth has been lost and how strong the remaining walls are, decided after examination and X-ray.
| Factor | Filling | Inlay / Onlay | Overlay / Tabletop | Crown |
|---|---|---|---|---|
| Coverage | Inside cusps | 1-2 cusps + chewing surface | Full chewing surface | Full 360 degree tooth |
| Material | Composite, GIC | Emax porcelain | Emax porcelain | Emax, Zirconia, Lava |
| Tooth removal | Just decay | Decay + minor shaping | Decay + chewing surface shaping | Significant |
| Lifespan | 5 to 7 years | 10 to 15 years | 10 to 15 years | 10 to 15+ years |
| Visits | 1 | 2 | 2 | 2-3 |
| Best for | Small-to-moderate decay | Mid-large cavity | Large cavity not needing full crown | Structurally compromised tooth |
Why Picasso for Inlays and Onlays
Pressed Emax Lithium Disilicate
Every inlay, onlay and overlay at Picasso is pressed Emax lithium disilicate, the same material used by top cosmetic clinics in Sydney and Paris. High flexural strength, naturally translucent, and a 5-year material warranty.
iTero Digital Impressions
No putty trays. The iTero scanner captures the prepared tooth in minutes with sub-30-micron accuracy, so the porcelain seats precisely on the first try and the bond margin is sealed cleanly.
Lab-Fabricated, Not Chairside-Milled
We send cases to the lab for pressed-ceramic fabrication rather than milling chairside blocks. Pressed Emax is stronger, better shaded and better fitting than same-day milled equivalents.
Tooth-Coloured, No Metal
Pure ceramic. No metal substructure, no dark margin appearing at the gum line over years. The restoration matches your natural tooth in normal lighting and under flash photography.
Preserves More Tooth Than a Crown
Where a crown would remove 360 degrees of tooth structure, an inlay or onlay only restores the missing part. We do not upsize a case to a crown when the cusp walls are still healthy.
Honest Case Selection
If your tooth really needs a full crown (after a root canal, with multiple fractured cusps, or with very deep decay) we will tell you. An inlay placed on the wrong tooth fails within a year. We are not interested in that outcome.
Inlay, Onlay and Overlay Pricing
Per-tooth pricing in writing after consultation. Final quote depends on which restoration the tooth needs, decided after examination and X-ray.
| Service | Price | Warranty |
|---|---|---|
| Composite filling, small | 1 year | |
| Composite filling, large | 1 year | |
| Porcelain inlay / onlay: Emax | 5 years | |
| Porcelain overlay / tabletop: Emax | 5 years | |
| Re-cement inlay / onlay | - | |
| Crown: PFM | 5 years | |
| Crown: Emax | 7 years |
If the tooth needs full coverage, see porcelain crowns. For front-tooth cosmetics, see porcelain veneers.
When We Recommend an Inlay or Onlay Over a Crown
Partial coverage is the right tool when the tooth still has healthy structure. We preserve what is there.
Large Cavity, Cusp Walls Intact
Decay or an old filling occupies the central chewing surface, but the surrounding cusps are still solid. An inlay restores the centre without grinding away the healthy walls.
Single Fractured Cusp
One cusp has chipped or fractured on an otherwise structurally healthy tooth. An onlay covers the failed cusp and bonds to the remaining ones, which is more conservative than a full crown.
Replacing an Old Large Filling
An aging amalgam or composite filling has cracked, leaked or worn. The cavity is now too big for another filling but the walls are still intact. Inlay or onlay is the textbook upgrade path.
Avoiding Aggressive Crown Preparation
You want to keep as much natural tooth as possible. A crown removes 360 degrees of tooth structure, an inlay or onlay only removes what the case demands. Less is more when the case allows it.
When We Recommend a Crown Instead
Some teeth genuinely need full coverage. Here is when we will say so, even if you came in asking for an inlay.
The Tooth Has Had a Root Canal
Root-canal-treated teeth become brittle and are at high risk of vertical fracture. A full crown holds the tooth together and is the standard of care after endodontic treatment, not an inlay.
Multiple Cusp Fractures
If two or more cusps are already broken, the remaining walls are too thin to support partial-coverage porcelain reliably. A crown distributes the bite load across all walls evenly.
Decay Below the Gum Line
When decay extends below the gum line, the bond margin of an inlay would sit under the gum and be hard to seal cleanly. A crown is easier to finish and maintain at a deep margin.
Very Thin Remaining Walls
If the remaining tooth walls are paper-thin, they will fracture under chewing forces around any partial-coverage restoration. A crown wraps and protects the entire tooth.
How Inlay and Onlay Treatment Works
Five steps over two visits, roughly 10 days apart.
1. Examination + X-ray
Clinical exam and periapical X-ray confirm whether the cavity or fracture is too large for a filling, and whether the cusp walls are intact enough to avoid a full crown. We show you the X-ray and explain the options.
2. Tooth Preparation
Local anaesthetic. Existing decay or the old filling is removed. Minimal cusp shaping is performed only as the inlay, onlay or overlay shape requires. We preserve every healthy wall we can.
3. iTero Digital Impression
The prepared tooth and surrounding bite are captured with the iTero scanner in a few minutes. The digital case is sent to the lab the same day for shade matching and pressed-ceramic fabrication.
4. Temporary + Lab Fabrication
A temporary restoration is placed to seal the prepared tooth so you can eat and brush normally. Over the next 10 days the lab presses, finishes and glazes your final Emax restoration.
5. Final Fit + Cementation
Second visit. Temporary off, fit and bite checked, porcelain bonded with light-cured adhesive cement, polished. You leave with the restoration in final place. No further visit needed.
Aftercare
Brush, floss and eat normally. 6-month hygiene visits to preserve the bond margin. Replacement is usually only needed at 15 years if the porcelain or margins begin to show wear.
Who Is, and Isn't, a Good Candidate?
Inlay and onlay treatment suits most mid-to-large cavities on back teeth where the cusp walls are still healthy. It is the wrong tool for some cases. Here is the honest version, decided after examination and X-ray.
You're a Strong Candidate If
Your cavity or old filling is too large for another filling but the surrounding cusp walls are intact.
One cusp has chipped on an otherwise structurally healthy tooth.
You want to preserve as much natural tooth as possible and avoid the more aggressive preparation of a crown.
Your gums are healthy with no active decay on the same tooth.
You can attend two visits roughly 10 days apart.
An Inlay May Not Be Right If
Your tooth has had a root canal, full coverage with a crown is the standard of care.
Two or more cusps are already fractured, the remaining walls are too thin for partial coverage.
The decay extends below the gum line, the bond margin would be hard to seal.
You grind heavily without protection, partial-coverage porcelain can fracture under repeated load.
The tooth has very deep decay reaching close to the nerve, root canal treatment may be needed first.
Aftercare
Inlays and onlays are cared for like natural teeth. The maintenance is mostly normal hygiene, with two short-term notes during the temporary phase.
Normal Brushing and Flossing
Brush twice daily and floss once daily as you would around a natural tooth. The Emax surface is glazed ceramic and resists plaque well.
While the Temporary Is In
Avoid sticky foods (toffee, chewing gum) on the temporary. When flossing on that tooth, pull the floss out sideways rather than snapping it up to avoid dislodging the temporary.
Eating After Final Cementation
Once the final restoration is bonded you can eat normally, including hard and crunchy foods. The pressed Emax has high flexural strength and is fully bonded to the tooth.
6-Month Recall Visits
Hygiene visits twice a year to clean the bond margin and check the porcelain for wear or marginal staining. This is the single biggest factor in restoration longevity.
Nightguard If You Grind
If your bite assessment shows grinding or clenching, we recommend a nightguard. Repeated grinding force is the main avoidable cause of porcelain fracture.
Replacement at 10-15 Years
Most porcelain inlays and onlays are replaced at 15 years when margins age or porcelain shows wear. We retain your digital records to speed up replacement fabrication.
Risks & Honest Tradeoffs
Inlays and onlays are a long-established restoration with strong clinical track records. No dental procedure is risk-free. Here is what can go wrong and how Picasso minimises the avoidable risks.
Marginal Staining Over Years
The bond margin between porcelain and tooth can pick up colour over years, especially in coffee, tea or red wine drinkers. This is cosmetic, not structural, and is one reason 6-month hygiene visits matter.
Fracture Risk Under Heavy Grinding
Pressed Emax is strong but not unbreakable. Patients who grind or clench heavily without a nightguard carry a higher risk of porcelain fracture. We recommend a nightguard wherever bite assessment shows grinding.
Retreatment Usually Means Upsizing
If the restoration eventually fails, the tooth has often lost more structure underneath. Replacement is typically by upsizing to a full crown rather than another inlay. This is the natural progression of restorative dentistry.
Sensitivity in the First Two Weeks
Some sensitivity to cold or pressure in the first one to two weeks after preparation is normal as the tooth nerve adjusts. It usually settles. Tell your dentist if it persists past two weeks.
Two Visits, Not One
Picasso uses lab-pressed Emax rather than chairside-milled blocks. The tradeoff is two visits over 10 days instead of a single same-day visit. The benefit is stronger, better-shaded, better-fitting porcelain.
What We Will Tell You No To
If your tooth genuinely needs a crown (root canal done, multiple cusps fractured, deep margin) we will say so. An inlay placed on the wrong tooth looks fine for a year and fails expensively after that.
Your Picasso Inlay and Onlay Team
Cases are led by our cosmetic dentist with surgical and clinical oversight from our Founding Clinical Director.
Dr. Huong Nguyen (Dr. Rosie)
Cosmetic Dentist. Leads inlay, onlay, overlay and other tooth-coloured restorative cases at Picasso. Designs the restoration shape, shade and bite using iTero digital impressions and works closely with our pressed-ceramic lab on every case.
Dr. Emily Nguyen
Founding Clinical Director. Founded the original clinic in Hanoi in 2013 and trained at Pearl Dental Clinic, Ho Chi Minh City. Sets clinical standards for case selection, preparation protocols and prosthetic delivery group-wide.
Common Questions
What's the difference between an inlay and an onlay?
An inlay sits inside the cusps of the tooth, like a precision-fit filling. An onlay covers one or more cusps but not the full tooth. An overlay (or tabletop) covers the entire chewing surface but not the sides. All three are partial-coverage restorations and preserve more natural tooth than a full crown.
Why not just use a regular filling?
For small to moderate cavities a composite filling is the right tool. Once the cavity is large, fillings flex under chewing forces, leak at the margins and tend to fail within 7 years. A pressed Emax inlay or onlay is fabricated outside the mouth to a precise digital fit and commonly lasts 15 years.
Why not just place a crown?
A crown removes 360 degrees of tooth structure to seat over the entire tooth. If the cusp walls are still healthy, that is more removal than the case needs. An inlay or onlay preserves the intact tooth walls and only restores the missing part.
Will it match my tooth colour?
Yes. Emax pressed lithium disilicate is shade-matched in the lab to your surrounding teeth. There is no metal substructure, so the restoration looks like natural tooth in normal lighting and under flash photography.
How long does a porcelain inlay or onlay last?
Picasso provides a 5-year material warranty on all Emax inlays, onlays and overlays. With good hygiene and 6-month recall visits, well-bonded restorations commonly last 15 years before needing replacement.
Does the procedure hurt?
Tooth preparation is performed under local anaesthetic and is comfortable. Some sensitivity to cold or pressure is normal in the first one to two weeks after preparation and usually settles. Tell your dentist if it persists past two weeks.
Can I eat normally afterwards?
Yes, after final cementation you can eat normally. While the temporary is in place between visits we recommend avoiding sticky foods (toffee, chewing gum) and being gentle when flossing on that tooth.
Do I need a temporary between visits?
Yes. The lab takes 10 days to press and finish your Emax restoration, so we fit a temporary at the first visit to seal the prepared tooth. The temporary lets you eat and brush normally during the wait.
Can an old inlay or onlay be replaced?
Yes. If the porcelain fractures or the margins age, we remove it and either replace with a new inlay/onlay or, if the underlying tooth has weakened further, upsize the restoration to a full crown. We retain your digital records to speed up replacement fabrication.
Can it be done in one visit?
Picasso uses lab-fabricated pressed Emax rather than chairside-milled blocks, so the standard protocol is two visits over roughly 10 days. The lab process produces stronger, better-fitting and better-shaded restorations than same-day milled options.
Start Here
Save the Tooth.
Don't Over-Treat It.
Book a free consultation. We'll examine the tooth, take a periapical X-ray, show you what is there and what is missing, and recommend the smallest restoration that will last: filling, inlay, onlay or crown. Quoted in writing before any clinical work begins.