The Importance of Cutting Geometry in CAD/CAM Milling Machines.

No matter how precise the CAD/CAM cutters used in dental milling machines may be, certain details—which are easily overlooked in daily use—have a significant impact on the fabrication of dental restorations. For example, have you ever wondered why a particular CAD/CAM bur has a longer or shorter service life than another? Or have you ever wondered why certain tools can only process a certain number of dental restorations before they break?

Well, these and other problems are related to various technical characteristics of CAD/CAM milling tools, and although few people realize it, understanding the technical aspects of tools for the digital workflow and selecting the right tools can lead to an exponential increase in efficiency in the fabrication of dental restorations. Furthermore, it helps you find CAD/CAM bur bits with a longer service life, thereby reducing operating costs since you’ll need to replace them less often.

In this article, you'll learn how important the right cutting geometry is for CAD/CAM milling cutters when manufacturing dental restorations using digital workflows. Be sure to check it out!

Due to the unique properties of each component produced by dental milling, the cutting geometry of the milling cutter becomes a key distinguishing feature for the final results; it is considered a decisive factor for the surface quality of the component and is essential for the longevity of the milling cutter. The cutter’s cutting geometry ensures high-precision milling of dental materials, produces surfaces suitable for the final product, minimizes the need for rework, and enables a perfect fit between parts that require a precise connection.

This requires qualified engineers and testing laboratories to ensure that a bur has the geometric properties suitable for each type of dental material. OSG uses state-of-the-art equipment, such as robust and extremely precise 5-axis CNC machine tools, to create these high-precision geometries with the goal of achieving a perfect milling result; these geometries have been specifically designed to enhance the tool’s strength and performance.

During the dental milling process, the cutting tool removes chips (machined material) through rotational and feed movements, while the material shifts in linear and angular motions. A well-executed machining process involves the effective formation and removal of chips. To machine the material, the cutting edges of the milling cutter feature various rake angles (cutting angles) and clearance angles, which have been designed and tested to ensure optimal performance between the material and the milling cutter.

To machine the material, the grooves on the milling cutter are wedge-shaped; the wedge angle determines the cutter's fracture resistance. This means that the smaller the wedge angle, the lower the cutter's fracture resistance, although this property depends on the type of material being milled.

Learn more about the key challenges in dental milling:

• High strength of the materials to be machined;
• Inconsistent interpretation of mathematical texts leads to the removal of large amounts of material;
• Difficulties in removing chips from deep cavities;
• Long oscillation strokes that generate vibrations;
• Tight milling paths and tolerances;

The optimal balance between angles and clearances—which defines the cutting geometries—is crucial for overcoming the challenges mentioned above, extending the milling cutter’s service life, and ensuring greater precision and better surface quality of the milled parts.

The geometries of OSG's CAD/CAM milling cutters ensure a smooth cut in key dental materials such as ceramics and zirconia, thereby enabling high-quality restorations such as crowns, veneers, onlays, and inlays.

3 Tips for Minimizing Tool Breakage During Dental Milling?

• Keep track of the milling cutter's service life. The tool should be removed from the machine due to wear, never because it has broken, as this increases the risk of damage to the milling machine.
• Perform efficient planning in CAM to minimize the risk of collisions and ensure that the cutter path is as unobstructed as possible for effective cutting.
• Ensure efficient cooling and make sure there is never a shortage of coolant so that the milling cutter retains as little heat as possible.

OSG milling cutters were developed for use at the highest cutting speeds on the market’s leading milling machines, and all cutters were manufactured to the highest standards of quality and precision, ensuring compatible tool holders for fast and precise tool changes in any milling machine system.

Now that you understand the importance of cutting geometry in CAD/CAM milling machines within the digital workflow, it is important that you apply this knowledge when making decisions about purchasing new tools for your milling machine.

Keep in mind that choosing the right tools can lead to significant efficiency gains and cost savings in the medium and long term—not to mention much more precise results in dental procedures.

OSG CAD-CAM milling cutters are the perfect choice for precise milling with exceptional tool life. Thanks to extensive research by our engineering team, we bring dental tools to market that deliver above-average performance and enable you to mill more components with greater precision, longer tool life, and the best value for your money. So make the right choice when purchasing tools for your milling machine!

Visit our online store and discover our complete line of tools for the leading digital milling machines on the market!