Dental clowns are small, miniature objects that require precise and high-tolerance machining capabilities to achieve the best shape, size, and fit inside a patient’s mouth. That level of accuracy is very tough to achieve if done with manual machining, so the right option for machining these products is CNC machines. However, as CNC machines come in various shapes with different specifications, which one is needed for manufacturing dental crowns? The answer is 5-axis CNC milling machines, as they are one of the finest options of machining out there that can help in making dental crowns. So, let’s dive deep into finding out how CNC milling machines can help in making the best dental crowns.
Why should one choose 5-axis milling machines for machining dental crowns?
Here are some of the top reasons why you should choose 5-axis milling machines for machining dental crowns:
- Complex geometry handling: Dental crowns are highly complex 3D structures and are not some easy to machine, plain, and flat object, so they require high-end CNC machines that can design those complex shapes. They possess highly complex 3D contours, including occlusal surfaces with cusps and fissures, interproximal contacts, and precise marginal fits. A 3-axis or 4-axis CNC machine will struggle to approach the object from different angles and build the product, and will need multiple setups to get this done, which increases the probability of human error and inaccuracies. Only precise milling of 5-axis machines from multiple angles is the right choice for developing those anatomical details in just one setup.
- Superior marginal fit and adaptation: One of the most important aspects of a dental crown is its marginal fit. An ill-fitting crown can lead to different problems like irritation in the gum, recurrent decay, and eventually restoration failure. 5-axis milling helps with the extremely precise cutting, which will ensure a tight fitting of the crown and enhance the longevity of the restoration.
- Better surface finishing and aesthetics: the multi directional movement feature of the multi axis CNC milling machines helps to achieve a much more smooth surface finish. This reduces the need for any polishing or surface finishing after the initial machining work is done, which saves time, labour, and cost. For aesthetic restorations like ceramic or zirconia crowns, a smooth surface is crucial for achieving a natural, lifelike appearance that blends seamlessly with the surrounding teeth.
- Material versatility: Dental crowns are made of different kinds of materials, and they have unique properties like:
- Zirconia: This material is known for its exceptional strength and biocompatibility, used for posterior crowns, and typically requires dry milling.
- Lithium Disilicate: They offer excellent aesthetic and good strength, and they are mostly used for anterior crowns, and need wet milling.
- PMMA (polymethyl methacrylate): This material is used for temporary crowns and long term provisionals.
- Metal alloys (CoCr, Titanium): These materials are used for full metal crowns or frameworks for porcelain fused to metal crowns.
What type of milling?
Dental equipment may need different types of milling, so let’s check which type of milling is needed for what purpose:
- Dry milling: Dry milling is suitable for materials like PMMA, resin, wax, and Zirconia, and is optimized for speedy and efficient machining. Compressed air or vacuum is used for dust removal. Air cooling helps to avoid water contact with Zirconia and keeps the method much more clean.
- Wet milling: This process of milling is done by using coolant to reduce heat and friction. This method of milling is more suitable for different hard and brittle materials like Lithium Disilicate, glass ceramic, titanium, cobalt chrome, etc. This method is more commonly used to give a smoother surface finish, helping in aesthetic restorations like anterior crowns.
- Hybrid milling: There are some hybrid milling machines, too, that support both wet and dry milling functions, which is ideal for labs and machining shops that handle diverse kinds of materials.
Top multi axis CNC machines you might look for to make dental crowns:
- Amann Girrbach Ceramill Motion 3
- Dentsply Sirona inLab MC X5
- Ivoclar Vivadent PrograMill PM 7
- Roland DGSHAPE DWX‑52DCi
Conclusion:
Dental crown manufacturing is a bit complex due to the requirement of high precision, tight tolerances, suitability with different materials, and different types of milling procedures. So, make sure to buy the right machine after doing enough research, and in case you’re looking for any used CNC machines, then you must check our collection of used CNCs.
