What are dental inlays and onlays?
An inlay is an indirect restoration that sits within the cusps of the tooth, while an onlay covers one or more cusps: both restore a damaged tooth while keeping most of the healthy tooth structure.
Many patients come in with a broken back toothafter years of tooth decaythat progressed quietly. The damage is too large for a regular filling, but does not justify a full crown. In that situation, an inlay or onlay is often a suitable solution. At Dr Haim Aseriel's clinic, these restorations are made from metal-free ceramic materials such as zirconia and E-MAX.
Inlay vs onlay: what is the difference?
Cusps are the raised points on the chewing surface of a back tooth. When decay or a crack stays in the center of the tooth, an inlay can fill the space; when a cusp is weakened or broken, an onlay rebuilds and protects it. A crown goes one step further and covers the entire tooth.
| Criterion | Filling (composite) | Inlay | Onlay | Crown |
|---|---|---|---|---|
| What it covers | A cavity inside the tooth, built up directly in the mouth | The area within the cusps | One or more cusps | The whole tooth |
| Healthy tooth removed | Only what the cavity requires | Least | Limited | Most |
| Typical situation | Small to medium damage | Damage too large for a filling, cusps intact | Weakened or broken cusp, sound root and walls | Too little sound tooth left |
| Visits | One | One in suitable cases (on-site lab), otherwise two | One in suitable cases, otherwise two | One in suitable cases, otherwise two |
| Survival in studies | About 1%–3% failure per year on back teeth (Demarco et al., 2017) | 92%–95% at 5 years, about 91% at 10 years, ceramic (Morimoto et al., 2016) | 92%–95% at 5 years, about 91% at 10 years, ceramic (Morimoto et al., 2016) | About 92%–97% at 5 years, depending on the material (Sailer et al., 2015) |
Inlay vs filling: when is a filling not enough?
A dental filling is placed directly in the tooth in a single visit and remains the standard treatment for most small and medium cavities. An inlay is made outside the mouth, in a dental lab, and then bonded in place; at the clinic, the lab is on site, so in suitable cases this is done the same day instead of over two visits.
An inlay or onlay is suited to cases where the damage exceeds what a direct filling can handle, but the root and walls of the tooth are sound. Large direct fillings are more exposed to wear and fracture: posterior composite fillings fail at a rate of about 1% to 3% per year, mainly depending on cavity risk and the size of the filling (Demarco et al., Braz Oral Res, 2017). These figures come from different studies from those on inlays and onlays and cannot be compared directly; the choice is made tooth by tooth after an examination.
How inlays and onlays are placed
An indirect restoration follows several defined steps that are worth knowing before treatment. At Dr Aseriel's dental clinic in Jerusalem, each step is explained to you in advance, in English.
- Tooth preparation: the damaged tissue is removed and a precise space is shaped to receive the restoration.
- Digital scan: the tooth is recorded with an intraoral scanner and its exact dimensions are sent to the clinic's own dental lab.
- Fabrication: in the clinic's lab, with CAD/CAM technology, for an accurate and natural-looking result; in suitable cases the inlay or onlay is ready and bonded the same day.
- Temporary restoration: when the restoration is not ready the same day, a temporary restoration or temporary crown protects the tooth between visits.
- Bonding: the restoration is bonded with a resin-based adhesive cement.
Most patients feel only mild discomfort and return to their daily activities within a day of treatment.
Benefits of inlays and onlays
The main benefit is that as much natural tooth structure as possible is preserved, unlike full-coverage restorations such as an E-MAX crown, which require more extensive reduction. A ceramic restoration has a shade and luster similar to a natural tooth, with no visible metal line at the gum.
91%
Ceramic restorations that survived 10 years (meta-analysis)
Mild sensitivity after treatment is possible and usually fades within days. If you have had sensitivity before, let the dentist know before treatment.
The ceramic surface is also harder and more wear-resistant than a direct composite filling. Fracture or cracking of the restoration, complications involving the nerve of the tooth and new decay at the margins are still possible (Morimoto et al., 2016), so good oral hygiene and regular check-ups are needed.
Examination, treatment plan and price quote
detailed and personalized
During the consultation, Dr Haim Aseriel examines your teeth, explains all the options and gives you a transparent price quote, with no obligation. The clinic is at 12 HaTnufa Street, Jerusalem.
Onlay vs crown: how do they compare?
Why choose an indirect restoration over a crown? Systematic reviews make it possible to compare the options.
In a systematic review, the average survival rate was 93.50% for onlays and 95.38% for full crowns (Vagropoulou et al., Journal of Oral Rehabilitation, 2018): a small difference, which makes it reasonable to choose the more conservative option when it is suitable. When too little sound tooth structure remains, an onlay is no longer appropriate and a crown, such as a zirconia crown, is considered.
93.50%
- Onlays: average survival rate in the review
95.38%
- Full crowns: average survival rate in the review
For example, a patient arrives with a fractured cusp on a back tooth. Without an appropriate restoration, the crack can spread until the tooth or root breaks; restoring the tooth early may stop the damage from progressing and lower the risk of more complex treatment such as root canal treatment. Even after an indirect restoration, fracture of the tooth or root is among the common complications (11.34% in the review by Vagropoulou et al., 2018), so early treatment and follow-up matter. Restoring several teeth is covered under full mouth rehabilitation.
How much do inlays and onlays cost?
The cost of an inlay or onlay depends on several clinical factors and is not the same for every patient.
The main factors are the material (ceramic, zirconia or indirect composite), the position of the tooth, the extent of the damage and the complexity of the preparation. Unlike a crown, which covers the whole tooth, an inlay is limited to the damaged area, which affects material costs and treatment time.
The clinic does not publish a general price list: after a full consultation with Dr Aseriel, you receive a detailed written quote with no obligation. Check that it lists tooth preparation, the temporary restoration, the lab work and bonding. The clinic also provides itemized receipts you can submit to your dental insurer; coverage depends on your policy.
You can also read patient reviews.
Inlays and onlays: a consultation in English
A prospective study that followed 60 indirect composite inlays and onlays reported an 85% success rate after 9 years (Galiatsatos et al., European Journal of Dentistry, 2022), results that support the long-term value of indirect restorations.
Dr Haim Aseriel, a US-trained dentist (DDS, NYU College of Dentistry), sees patients at 12 HaTnufa Street in Talpiot, south Jerusalem, open Sun 8:00–19:00 · Mon 9:00–19:00 · Tue–Wed 9:00–21:00 · Thu 8:30–21:00 · Fri 8:00–14:00. Call 03-912-1879 or use the contact form to book a consultation and a detailed quote.
Inlays and onlays: frequently asked questions
An inlay is an indirect restoration that sits within the cusps of the tooth (the raised points of the chewing surface), while an onlay covers one or more cusps. Both are made in a dental lab and then bonded to the tooth.
A filling is placed directly in the tooth in one visit and suits most small and medium cavities. An inlay or onlay is considered when the damage is too large for a direct filling but the root and walls of the tooth are sound. For comparison, posterior composite fillings fail at a rate of about 1% to 3% per year, mainly depending on cavity risk and the size of the filling.
An onlay preserves more of the natural tooth than a crown, which covers the whole tooth. In a systematic review, the average survival rate was 93.50% for onlays and 95.38% for full crowns, a small difference. A crown is preferred when too little sound tooth structure remains for an onlay.
Ceramic inlays and onlays usually last many years. According to a systematic review and meta-analysis, 92% to 95% of ceramic restorations survived 5 years and about 91% survived 10 years; fracture or cracking of the restoration was the most common cause of failure.
After an inlay or onlay, most patients feel only mild discomfort and return to their daily activities within a day. Sensitivity that lasts, or pain when biting, should be checked by the dentist.
Sources
- Morimoto S et al., Journal of Dental Research, 2016 – View study
- Vagropoulou GI et al., Journal of Oral Rehabilitation, 2018 – View study
- Galiatsatos A et al., European Journal of Dentistry, 2022 – View study
- Demarco FF et al., Brazilian Oral Research, 2017 – View study
- Sailer I et al., Dental Materials, 2015 – View study
