Bell-Everman Case Study: Rotary Motion Drives Chairside Dentistry System

Unique polar motion system reduces cost, improves performance.

Most of us don’t like to think about dental crowns. Odds are, however, that you will need one at some point in your life. Fortunately, this type of dental restoration is getting faster and easier for the patient, thanks to an emerging class of digital dentistry systems.

Think of these systems as rapid manufacturing cells that operate within the dentist’s office. The cells typically consist of an imaging system that takes a digital impression of the damaged tooth and a “chairside” milling machine that makes a ceramic crown. Customized, dentist-friendly CAD/CAM software allows the two pieces of hardware to work together—translating the imaging data into machine tool code.

One of the main benefits of these systems is the time saved by eliminating the need for a dental lab to manufacture the crown. With a traditional restoration, many days can elapse between the physical impression to crown insertion. The digital crown procedure can take place within a single day, often in only a couple hours.

For all the promise of same-day crowns, the capital cost of digital dentistry systems has limited their adoption somewhat—but not for long. A new digital dentistry solution from IOS Technologies Inc. drastically reduces system cost without sacrificing performance.

A division of Glidewell Dental Laboratories, IOS has developed its chairside digital dentistry solution around three subsystems:

• FastScan® intraoral scanner, a compact 3D imaging device that can produce high- resolution digital impressions that are several times more accurate than a traditional impression.
• FastDesignTM CAD software guides the dentist through the scanning process and proposes the ideal custom restoration, then generates CAM instructions.
• TS150TM in-office milling system.

All three of these subsystems feature technical breakthroughs that improve the cost-to-performance ratio of chairside dentistry. However, any engineer interested in motion control or machine tool design should take a close look at the TS150 mill in particular.

Rather than the Cartesian motion system you might expect on a milling machine, the TS150 is based on a rotary motion and uses polar positioning coordinates. This non-intuitive approach to motion allows the system to achieve the precision and accuracy of digital dentistry systems costing 40% more. The polar motion system also offers design lessons that can be applied to non-dental applications such as CNC micro-machining and subtractive prototyping.

Read the full case study here: Rotary Motion Drives Chairside Dentistry System