Dental Inlays and Onlays: Ceramic Repairs for Larger Cavities

A dental inlay or onlay is a restoration made outside the mouth, usually in a dental laboratory or from a digital scan, and then bonded onto the tooth. An inlay is shaped to sit inside the tooth, between the raised points known as cusps, in the same area a filling would normally cover. An onlay is a little larger: it extends over one or more of those cusps to protect a weaker part of the tooth that a filling alone would not support well.

Both sit between a filling and a crown on the scale of dental repairs. A filling is placed directly into the tooth in a single visit; a crown covers the whole visible tooth. An inlay or onlay is used when the damaged area is too large or too shaped for a filling to hold up well, but enough healthy tooth remains that removing it all for a crown is not necessary.

At Er Dental Clinic, inlays and onlays are usually made in ceramic, matched to the colour of your surrounding teeth. This page explains when an inlay or onlay is considered, how treatment works, and how it compares with a filling or a crown.

Material: ceramic, made in a dental laboratory or milled from a digital scan and matched to your natural tooth colour.

Used for: a cavity or an old, failing filling that is too large or awkwardly shaped for a new filling, but does not need a full crown.

Inlay vs onlay: an inlay fits between the cusps of the tooth; an onlay also covers one or more cusps for extra support.

Visits: typically two visits, preparation and a digital scan, then fitting once the ceramic piece returns from the laboratory.

An inlay or onlay is usually considered once tooth decay has progressed beyond a small cavity, or when an existing filling has cracked, leaked or become too large to replace safely with another filling. Our tooth decay page explains how a cavity develops in stages and why the repair needed at each stage is different, an inlay or onlay typically applies once decay has reached a moderate size, before it is large enough to need a full crown.

Inlays and onlays are also used to repair a tooth that has become broken or heavily worn, for example from an old filling that has fractured under normal biting. Our broken and worn teeth page covers the wider range of causes and repair options in more detail; this page focuses specifically on the inlay and onlay restoration itself once that kind of repair has been recommended.

An inlay or onlay tends to suit patients who have lost a meaningful amount of tooth structure to decay, a cracked cusp or a failed filling, but who still have enough healthy tooth left that a full crown is not the only option. It is also considered for patients who prefer a restoration made outside the mouth, since a laboratory-made or milled ceramic piece can be shaped and polished more precisely than a filling placed and hardened in a single visit.

Your dentist confirms suitability from a clinical examination and X-rays, checking how much of the tooth remains, where the damage sits, and how your bite meets the opposite teeth, before recommending an inlay, an onlay, or an alternative restoration.

Treatment starts with local anaesthesia and removal of the old decay or failing filling, leaving a clean, well-defined shape for the new restoration to sit in. Once the tooth is prepared, a digital scan (using a system such as 3Shape) or a traditional impression records its exact shape, which is sent to the laboratory to design and produce the ceramic inlay or onlay.

A temporary filling protects the tooth while the finished piece is made. When it returns, your dentist checks the fit, shade and bite carefully before bonding it onto the tooth with a strong dental adhesive and polishing the surface so it blends with the surrounding tooth structure.

Some mild sensitivity to hot, cold or pressure is common for a few days after an inlay or onlay is bonded, particularly if the tooth was previously very sensitive, and it usually settles on its own. Over-the-counter painkillers can help if needed, and your dentist tells you what to expect for your specific tooth.

Brushing twice a day with a fluoride toothpaste and cleaning between your teeth keeps the restoration and the surrounding gum healthy. As with any bonded ceramic restoration, it is worth avoiding biting directly into very hard foods, such as ice, and attending regular check-ups so your dentist can review the fit and margins over time.

A well-fitted inlay or onlay restores the shape and biting surface of a damaged tooth while keeping more of the natural tooth structure than a crown would require. Because the ceramic is matched to your tooth colour and made outside the mouth, the fit and surface finish are often more precise than a large filling placed and shaped in a single visit.

How the tooth performs afterwards depends on the size of the original damage, your bite, grinding habits and how well the restoration and surrounding tooth are looked after. Your dentist explains what is realistic for your specific tooth based on your examination and X-rays before treatment begins.

Two visits are usually needed. Because the ceramic piece is made in a laboratory or milled from a scan, a temporary filling covers the tooth between your preparation visit and the fitting visit, unlike a filling that is finished in one appointment.

Not suitable for very large damage. If too little of the tooth remains, an inlay or onlay does not provide enough support and a crown is recommended instead.

The restoration itself can eventually need replacing. Like any dental restoration, an inlay or onlay can wear, chip or come loose over the years, and cleaning around its edges matters for the health of the tooth underneath.

Your dentist explains the risks that apply to your specific tooth, based on your examination and X-rays, before you give your consent.

Inlay and onlay treatment at Er Dental Clinic is assessed and planned by Dt. Vijdan Aslanoğlu, alongside our other dentists. Whether a tooth needs a filling, an inlay, an onlay or a crown is confirmed individually from a clinical examination, X-rays and your bite, and your written treatment plan states which restoration is proposed for each tooth and why.

The clinic holds an International Health Tourism Authorisation Certificate issued by the Republic of Turkiye Ministry of Health (certificate no. ST-6264), which you can check on the e-Devlet document verification service at turkiye.gov.tr/saglik-bakanligi-ebys.

If your dentist finds that a smaller repair is enough, a standard tooth filling may cover the damage in a single visit; our tooth fillings page explains composite fillings and how old amalgam fillings are assessed.

If more of the tooth needs support than an onlay can provide, a dental crown covers the whole visible tooth; our dental crowns page explains the different crown materials we offer.

Where decay has reached the nerve of the tooth, root canal treatment is needed before any restoration is placed on top, and an onlay or crown is often recommended afterwards to protect the tooth from fracture.

If the cause of the damage is grinding or clenching rather than decay alone, addressing that with a night guard alongside your restoration can help protect it from further wear.

Inlays and onlays are one part of general dentistry at Er Dental Clinic. The pages below cover related treatments and prevention.

These four repairs sit on a scale from smallest to most extensive. A filling is placed directly into the tooth and does not cover any cusps. An inlay is made outside the mouth and sits between the cusps, in roughly the same area a filling would cover. An onlay is also made outside the mouth but extends over one or more cusps for extra support. A crown covers the entire visible tooth once it has been prepared.

Which one fits your tooth depends on how much natural structure is left and where the damage sits, which your dentist confirms from your examination and X-rays. If a crown turns out to be the better option for your tooth, our inlay vs onlay vs crown page explains that comparison in more detail.

Send us your photos or X-rays for a free online consultation. Our dentists will give an initial view on whether a filling, an inlay, an onlay or a crown fits your tooth, and reply with a written treatment plan and a clear quote, so you can compare your options before you decide to travel. You can also contact us directly with any questions.