2X Faster 10X Safer... with 3GEN Reamers Upgraded the Break-R-Way

With the breakthrough, 3GEN Reamers it is now possible to, rapidly and safely, shape the canal spaces with rotary instruments.
Patent Pending on the 3GEN Reamer with High Strength Hybrid Cutting Flute upgraded the Break-R-Way. This is how it works...

1. It is not necessary to buy more special equipment...
    3GEN Reamers can even be used with a standard, (20,000 rpm), dental slow speed hand piece.
2. 3GEN Reamers are technique insensitive as broken or separated rotary instruments can easily be retrieved by dental assistants.
3. Instead of marking 3GEN Reamers until a predetermined scrap date, they can be used until breakage/separation.
4. Patients are very grateful to have shorter, one visit, root canal treatments and more patients can be treated per day.
    Please click here to read more about the New 3GEN Reamer...

Making NiTi Rotary File Separation a Non-Issue
(Information about the Patented Break-R-Way Upgrade)
By Duane E Cox, D.M.D.

This presents a new approach to solving NiTi Rotary file separation. The author gives detailed information on how engineering controls placed in the rotary files can make the separated files easily retrievable. 

Background
Anxiety for clinicians is a recurring problem over concerns of the Ni-Ti rotary file separation. It is well documented in the dental literature how difficult or impossible a file segment is to remove. Also documented are the consequences and protocol for informing patients and referral to an endodontist.

Current solutions offered are numerous but not 100% effective . 
Solutions include:

• recommendations to single use file
• using the files at very low rpm's
• using files in a crown down technique
• using light apical forces
• using apical forces briefly, etc.

Engineering controls have not been built into the files previously publicly presented

New Approach
It is readily apparent to the dental clinician how Gates Glidden burs always separated near the handle. By contrast, Ni-Ti rotary files when over stressed, separate in the smaller diameter section of the cutting flutes.

When threaded pins were popular, they were designed to shear at a pre-determined location on the pin. The research began with this point. The spring and summer of 2003 were spent developing the idea, patent searching and having custom equipment built.

An annular groove method to modify existing Ni-Ti rotary files could be used in the fall of 2003. It was difficult to achieve the desired precision of within 0.01mm. The most difficult question to solve was exactly how much to weaken the files at the SSP (safe separation point). 

If the modified files were overly weakened, they would easily break at the SSP without doing much work. On the other hand, if the files were not weakened sufficiently, they would deform and/ or separate as before.

A process was developed by experimentation/elimination to within 0.01mm the optimum diameter to leave at the SSP for that design, taper, length, and tip size.

The number of file uses did not effect this or times run through the autoclave. This SSP logically seemed to be 1mm to 2mm from where the shaft meets the handle for maximum ease of removal.

Clinical Trials
Having Ni-Ti rotary files modified to optimum values allowed clinical trials to begin in January of 2004. It was pleasantly surprising that the majority of Ni-Ti commercially available rotary files are suitable for modification. Without as much fear of file separation, a crown down technique was no longer "absolutely set in stone".

The optimum values determined had to be rigidly adhered to however or file separation would occur as previously. By using 25mm length files as much as practical, separated file segments were easily removed with cotton pliers, hemostats, needle holders, etc.

In a few instances, "serious wrestling" with needle holders for 10 to 30 seconds was necessary to remove the file segment. Dislodging motions used were "anything but clockwise or apically". 

All file segments were recovered from the canal space and were normal in appearance. They had not "locked in" to the canal spaces with forces requiring referral for removal of the file segment.

Summary
By working in a small group of practices the author had a chance to test the validity of the engineering controls built into the Ni-Ti rotary files. Although not practical for all current rotary files, this annular groove modification at a SSP was successful enough to warrant clinical usage to create more "user-friendly" files. With time this safety upgrade should become the "standard of care" as much as rubber dam usage.

By Duane E Cox, D.M.D.