CAD/CAM in Dentistry

CAD/CAM is one stage in a longer process. A dentist examines you, decides what the tooth needs and prepares it (shapes the tooth so that the restoration will fit). The restoration is then designed and made. Finally, the dentist checks it in your mouth and fits it. The stages before and after manufacture are much the same as for conventionally made work.

What it is used for

• Crowns, inlays, onlays and veneers. Ceramic restorations for single teeth can be milled. Our pages on dental crowns and on inlays and onlays explain those treatments and their risks.
• Bridges and implant parts. A 2014 review notes that systems were developed to make implant components and prostheses¹ as well as restorations on natural teeth.
• Temporary crowns and bridges. These can be made by hand, or milled or 3D-printed².
• Dentures. Complete dentures can be made conventionally, or milled or 3D-printed³.
• Models and surgical guides. A 2021 review names working models for diagnosis and surgery⁴ as the most common use of 3D printing in dentistry. A 2014 review says one printing method is routinely used to make resin surgical guides¹ for implant placement.

At the clinic or in a laboratory

Design and manufacture can happen in a dental laboratory or, where the equipment exists, at the clinic (chairside). A 2017 review describes clinics equipped to design and mill restorations themselves⁵ from the scan. A crown milled at the clinic can, in suitable cases, be fitted in one appointment. Work made in a laboratory usually needs more than one appointment.

Your dentist will tell you which applies to your treatment and which laboratory makes your restoration, and you can ask for this in writing. Our dental laboratory page explains what a laboratory does.

The design can only be as good as the record it starts from. Whoever designs the restoration needs:

• The prepared tooth and its neighbours. These are usually recorded with an intraoral scan. A conventional impression can also be the start: the impression, or a model poured from it, can be scanned to give a digital file⁴.
• The opposing teeth and the bite, so that the restoration meets the teeth it bites against.
• The shade. It is usually chosen with a shade guide in good light, sometimes with photographs as well. A 2025 review compared intraoral scanners with a measuring instrument (a spectrophotometer). It advised against choosing the shade with an intraoral scanner⁶, although its evidence was of very low certainty.
• For implants, the position of each implant. A small cylinder called a scan body is screwed onto each implant, so that the scan can record the implant's position in three dimensions⁵.
• The dentist's instructions: what to make, from which material, and in which shade.

A scan records only what the scanner can see. Edges under the gum are hard to capture, and blood may hide the edges⁵ of the prepared tooth. An unclear part can be deleted and captured again⁵. If the file reaches the laboratory while you are still at the clinic, the technician can ask straight away for another scan⁵. A problem found later may mean another visit.

Our digital scanning page explains how scans are taken and checked, and where their accuracy has limits.

In the design software, a dental technician or, for chairside work, the dentist works on the 3D model of your mouth. Ask who designs your restoration. Typical steps are:

1. Marking the edge. The edge of the prepared tooth (the margin) is located on the model¹.
2. Shaping the restoration. Its shape is fitted to the neighbouring teeth, the opposing teeth and your bite.
3. Checking the thickness. Each material needs a minimum thickness. One manufacturer, for example, gives minimum thicknesses for veneers and crowns⁷ made from its milled lithium disilicate. Where the restoration would be too thin, a 2014 review says a change to the preparation can be recommended¹. This can mean removing more of the tooth to make room.
4. Leaving room for the cement. The design leaves a thin space for the cement between the restoration and the tooth. If there is too much space, the restoration fits loosely; if there is none, it will not fit¹ unless it is adjusted by hand.

The design is checked on screen before it is sent to the machine. It is also a computer file: ask whether a copy can be kept with your records.

Milling (subtractive)

According to a 2014 review, milling is the most widely used computer-aided manufacturing method in dentistry¹. A computer-controlled machine mills the restoration from a larger block¹ with small rotating cutting tools (burs).

• Materials. Ceramics, metals including titanium, resins and waxes¹ can be milled.
• Consistent material. The blocks are made industrially, so milling relies more on the manufacturer's quality control¹ than on the laboratory's.
• Detail. Fine detail depends on the smallest bur, which is normally about 1 mm across¹.
• Surface. Milling a ceramic can leave tiny cracks and chips at the surface¹.

3D printing (additive)

3D printing, also called additive manufacturing, joins material to make an object from the 3D design, usually layer upon layer¹. Printers can produce objects in metals, resins or ceramics¹. Metal frameworks, for example, can be printed with a laser that melts a metal powder layer by layer¹.

• After printing. Excess material and the supports used during printing are removed¹. A printed resin object is rinsed and then cured further under ultraviolet light¹.
• Cost and time. A 2021 review lists high cost and time-consuming post-processing⁴ among the drawbacks of printing.
• Curing quality. A 2026 review notes that the curing of 3D-printed resins varies with the processing after printing⁸. Resin that is not fully cured keeps some unreacted monomer. The same review says such residual monomers can trigger delayed allergic reactions⁸, in patients and in dental staff. Tell your dentist about any reaction you have had to acrylic nails, adhesives or dental materials.
• Layers. Printing in layers can leave a stepped, coarse surface¹. The 2021 review adds that layering can make a material's properties differ from one direction to another⁴.

After milling or printing

Many restorations need further work after they leave the machine.

• Firing. Zirconia is milled from a pre-sintered block or disc, about a fifth larger than its final size⁹. It is then heated in a furnace over several hours (sintering), and shrinks to its final size and strength. Some lithium disilicate blocks are milled in a softer, partly crystallised state and then fired to reach their final strength, shade and translucency¹⁰. Others are crystallised by the manufacturer and need no firing¹⁰.
• Finishing. The surface is polished or glazed, and colour can be added with stains. To tailor its appearance, part of a restoration can be made thinner and then layered with porcelain⁷ by hand.

The material is chosen for the tooth, your bite and the appearance you want. The way the restoration is made follows from the material, not the other way round.

• Lithium disilicate, a glass ceramic often sold as e.max, can be milled or heat-pressed¹¹. Our lithium disilicate page explains its properties.
• Zirconia (often called zirconium). A 2014 review says that restorations made from high-strength ceramics such as zirconia are produced by computer-aided manufacturing¹. Our zirconia crowns page explains its types.
• Metals. Alloys and titanium can be milled¹, and metal frameworks can also be printed (see "Manufacturing methods").
• Resins for temporary crowns and dentures. A 2022 review compared temporary crown resins in laboratory tests. It concluded that, overall, printed ones were better in mechanical tests but worse in physical ones² than milled and conventional ones. In patients, a 2026 review found that conventional complete dentures held in place better³ than printed ones. On its other outcomes, such as patient satisfaction and chewing force, it found no significant difference between printed dentures and conventional or milled ones³. This does not show that they perform equally well. Our acrylic and prosthetic materials page explains these resins.

Products differ, even within one material. In a review of laboratory tests, lithium-based blocks from different manufacturers differed in composition and strength¹⁰. Your dentist will tell you which material, product and laboratory are used for each restoration, and you can ask for this in writing.

A machine makes what the design tells it to make. People check the work at each stage:

1. The record. The scan or impression is checked before it is used, and unclear areas are captured again.
2. The design. The edges, the contacts with the neighbouring teeth, the bite and the thickness are checked on screen before manufacture.
3. The restoration after manufacture. It is inspected for chips and flaws, and finished. A 2026 review of laboratory strength tests states that the success of a zirconia restoration depends on a surface without flaws or defects⁹.
4. The try-in. In your mouth, the fit, the edges, the bite and the colour are checked and adjusted if needed.
5. Fitting and review. A crown, inlay, onlay or veneer is cemented or bonded, and the bite is given a final check. Restorations on implants are fixed to the implant parts, and dentures are fitted in another way. The bite and the fit at the gum are usually checked again at a review appointment; ask when and where it will be.

Adjustments have limits. For zirconia, a 2014 review warns that adjusting it after sintering can weaken it¹. It says zirconia restorations should be made accurately so that hand adjustment is not needed¹. If your zirconia restoration is adjusted at the fitting, ask how the adjusted surface will be smoothed and polished again.

The same review notes that in many fit studies, researchers adjusted the inside of CAD/CAM restorations by hand¹ so that they would fit into place. It saw this as a sign that the systems did not always produce an accurate fit.

Ask who checks your restoration at each stage, and whether a record is kept of the material and the product used.

The findings below come from published studies, not from our own records. Most of these studies are several years old, and materials and machines have changed since. They concern the way a restoration is made. Our pages on dental crowns and on inlays and onlays explain the risks of the treatment itself, daily care and when to see a dentist.

Possible benefits

• No plaster model. When the work starts from a scan, no plaster model is needed⁵, and the file can be sent to the laboratory electronically⁵.
• Industrially made material. A 2014 review links milling from industrially made blocks with fewer manufacturing flaws, such as pores¹.
• Fewer appointments, in some cases. Where a clinic designs and mills crowns itself, one appointment can be enough in suitable cases (see "Where CAD/CAM fits in care").
• Fit on implants. For restorations on implants, the same review reports that milled ones fitted better than conventionally made ones¹ in the studies it read.

Limitations

• Survival compared with conventional work. A 2019 review pooled 14 clinical studies comparing ceramic restorations made by CAD/CAM with conventionally made ones. They covered 1,209 restorations in 957 patients, followed for two to seven years. CAD/CAM restorations failed more often: 2.62 against 1.48 failures for every 100 restorations followed for a year¹². The difference was statistically significant. When patients left a study early, their restorations were counted as still in place, so the failure rates may be higher. The review included laboratory milling, and its search ended in 2017.
• Survival on its own. A 2018 review pooled 2,916 single-tooth CAD/CAM ceramic restorations, followed for seven years on average. It estimated that 89.7 per cent were still in place after five years¹³. It had no conventional comparison group, and its search ended in 2016.
• Same-day work. Neither review assessed chairside (same-day) work separately¹², so they cannot tell us whether it lasts as long as laboratory work¹³.
• Pressed or milled. For lithium disilicate veneers, a 2025 review reported that pressed veneers fitted better at the edges and had higher survival over up to 10 years¹¹. Milled veneers had a better internal fit¹¹. Only one trial had a low risk of bias, and the authors rated the certainty of most results low or very low¹¹. So the review does not prove that pressed veneers are better.
• Fit on natural teeth. A 2014 review found no compelling evidence¹ that milling makes restorations on natural teeth more precise. On natural teeth, conventionally made ones tended to fit better¹. Each digital step, from scanning and marking the margin to design and milling¹, can add error.

Conventional methods are still in everyday use, and many restorations combine the two. In a conventional workflow, an impression is taken, a plaster model is poured and a wax pattern is made¹. The wax is then replaced with metal, ceramic or acrylic¹.

Reasons a conventional method may be chosen include:

• Pressed ceramic. Lithium disilicate can be pressed in a laboratory instead of milled (see "Benefits and limitations").
• Layered porcelain. To tailor the appearance of a restoration, porcelain may be layered by hand, sometimes over a milled core (see "Manufacturing methods").
• Long bridges and full arches. A 2017 review found that scans did not appear to have the same accuracy⁵ as conventional impressions for long bridges and full-arch work.
• Full-arch bridges on many implants. A 2025 review covered mostly laboratory studies. With more than four implants, it found conventional impressions slightly more accurate than digital methods taken together¹⁴ (intraoral scans and photogrammetry, a camera-based method). In the review's analysis by method, intraoral scanners on their own did not differ from conventional impressions¹⁴. This does not show that they are equally accurate.
• Edges deep under the gum. A scanner records with light, which, unlike impression material, cannot physically push the gum aside⁵. Some authors suggest combining the two methods⁵, partly using impression material. With either method, healthy gums are essential⁵ and bleeding has to be controlled.
• Complete dentures. In the 2026 review, conventional dentures held in place better than printed ones. On its other outcomes, it found no significant difference (see "Material selection").
• What the clinic and laboratory use. Not every clinic or laboratory uses every method.

Ask which method is planned for each restoration, and why.

Before treatment, ask in writing:

• how each restoration will be made: milled, 3D-printed, pressed or built up by hand;
• whether it will be made at the clinic or in a laboratory, and which laboratory;
• who designs it, and who checks the scan and the design;
• the material, the product name and the manufacturer of each restoration;
• what your written plan includes, and what happens if a restoration does not fit, chips or breaks.

You have the right to be told, on request, who the dentists and other staff treating you are, and their roles and titles¹⁵.

Records. Under Turkish rules, private dental clinics record the diagnosis, the treatment and any X-rays in detail, with tooth numbers¹⁶. You can examine your file and records and get a copy¹⁵. Ask for a written record of each restoration: the material, the product, the shade and the laboratory. Ask too for copies of your scan and design files, and ask in which format you will receive them and how long they are kept. A dentist who treats you later can then see what was made.

Consent. Under Turkey's patient rights regulation, you are told about other options, with their benefits and risks, and the possible consequences of refusing¹⁵. In private dental clinics, you are asked to sign a consent form for every intervention¹⁶. Two copies of the form are signed, and one is given to you¹⁵. Ask for your copy. A second opinion from another dentist gives you a point of comparison. You can say no, or ask to stop, at any stage. Once a tooth has been prepared, that step cannot be undone.