The digital horizon:
Dental CAD/CAM comparison of centralised and decentralised production

In the rapidly advancing dental world, digitalisation is not just a fad – it is the future. It starts with what we call the “digital twin”.

This can be obtained either by an intraoral scan directly in the patient’s mouth or by scanning a conventional impression.

Once we have the scan, we use state-of-the-art CAD software such as Exocad or 3Shape to design the perfect dental prosthesis.

The advantage? This digital approach offers precision and flexibility in planning, guaranteeing a high-quality result.

It is essential for dental laboratories to maintain their role in the value chain. Independent design using CAD ensures that the laboratory can contribute its expertise, retains a full overview and bears responsibility for the end product. The laboratories have the time prioritisation in their own hands and can often act more cost-efficiently, as they can usually offer the service more cheaply than an external service.

But what if you want to outsource the design to manufacturing service providers such as CADdent? They can optimise the designs directly according to the manufacturing requirements. However, the argument is weakened because manufacturers also provide design recommendations to fulfil the requirements. Depending on your point of view, the lower labour requirement in the laboratory due to outsourcing can be an advantage or disadvantage.

Advantages of CAD in-house services:

• Contribution of own expertise
• Time prioritisation is at your own discretion
• Generally cost advantage compared to external services

Advantages of external CAD services by manufacturing service providers:

• The design is created directly according to the production requirements
• Less manpower required in the laboratory

After carefully weighing up the decision between in-house CAD services and outsourcing to service providers such as CADdent, the focus now shifts to the actual production process: turning the digital design into a physical work of art.

The design is converted into the familiar STL format, an essential link for most production methods. However, the real work of art only begins now: the data set must be prepared according to the chosen production method.
If you opt for LaserMelting, a common additive manufacturing process for metal dentures, your design is placed on a virtual production plate using a specific software. In addition, the designs are connected to this plate by support structures. Once a complete production plate has been placed, the data records of the print job are sliced, i.e. virtually divided into layers, using the software. This layer-by-layer information is then transferred to the machine software. The additive production system then begins the manufacturing process and creates the desired components layer by layer according to the transferred data.

Milling technology? A slightly different approach. In contrast to additive manufacturing, in which the dental prosthesis is placed on a production plate, the milling technique nests the designed dental prosthesis in a virtual milling blank. This requires careful alignment of the component according to the milling machine. The design must be positioned in such a way that the machine’s milling tool can reach every necessary point and carve the component out of the blank from any required angle. In addition, the components are provided with holding pins in the software. These pins hold the milled component securely in the blank and prevent it from moving during the milling process.

Depending on which production method you choose, there are different subsequent steps. In LaserMelting, for example, the components must be subjected to a thermal process to reduce process-related stresses which arise within the metal components during the manufacturing process. Only after this process the components can be sawn off the construction panel. The result: a distortion-free and precise component.

In other processes, such as milling, the components are not simply detached from their original blank for further processing. After separating the milled components from the milling blank, the retaining pins must be carefully ground using specific tools. If the material is zirconium dioxide, the milled component is then sintered to ensure that the ceramic retains its valued material properties.

There is a lot to consider when deciding whether you should produce in the laboratory or centralised. Production in your own laboratory has the advantage that no time is lost on transport routes, you have an overview of the entire process and are not dependent on external service providers. With LaserMelting in particular, however, the high acquisition costs for the production system, the sieving system for powder preparation and the annealing furnace must be taken into account. This process also requires a great deal of expertise and experience. To ensure the economic efficiency of the machine, it is crucial to utilise it well: the fuller the production plate, the lower the unit costs.

Milling in the laboratory incurs medium-high acquisition costs, particularly for the milling machine and the sintering furnace for ceramics. Although the process is simpler than LaserMelting, the consumables, especially in large quantities, must be taken into account.
On the other hand, centralised large-scale production offers advantages through the bundling of expertise, an optimised workflow and favourable purchase prices due to bulk purchasing.

Production in the laboratory:

• No transport times
• Complete process control
• Independence from third parties

LaserMelting in the laboratory:

• High acquisition costs
• Great expertise required
• Cost-effectiveness due to capacity utilization

Milling in the laboratory:

• Medium-high acquisition costs
• Simpler process
• Volume discounts for consumables

Centralised large-scale production:

• Bundling of expertise
• Optimised workflow
• Volume discounts for purchasing

When it comes to buying production systems and software, you should not just focus on the price. The main focus should be on the quality of the components which come out of a production system. Before deciding on a particular machine, it is advisable to carry out benchmarks and compare different manufacturers.
The production speed also plays a decisive role. For LaserMelting production systems in particular, the speed can be significantly increased by purchasing a machine with multiple laser heads. Although this increases investment costs, productivity increases significantly. Dual lasers are now standard in most industrial plants.
The compatibility of the software with the machines is another important point. Many machine manufacturers cooperate with certain software manufacturers so that the CAD/CAM workflow between the setting software and the machine is optimised. It is therefore advisable to follow the recommendations of the machine manufacturer.

The level of investment costs is not necessarily the decisive factor for the production costs per component. More important is the utilization of the machine and the workflow around it. Machines are designed to work continuously and this potential should be xploited in order to produce economically. This means that the entire process should be thought through and outlined before purchasing a machine. It is also important to ensure that there are enough orders to keep the machine running at full capacity.
In addition, you must not forget to invest in safety measures at work such as fire protection, extraction and other health and safety equipment. It’s not just about pure machine potential, but also about ensuring safe and efficient operation.