What File System Do I Use?
When I talk with general dentists—or even fellow endodontists—the single most common question I get is: “What file system do you use?”
My answer is simple: “All of them.”
One of the biggest advantages of doing my endo residency at Columbia was the freedom to experiment. I wasn’t pigeonholed into a single system, so I had the chance to try a wide variety. In my opinion, every resident should do the same—test out different systems and figure out which one works best for you.
The Golf Analogy
I used to follow golf closely and was fortunate enough to watch professional players practice in person. These are the best golfers in the world, yet I saw some of them hitting shots with one arm on the “wrong” club—just to train. Of course, that’s not how they compete in tournaments, but it showed me something important: great players can make it work under almost any condition.
The same applies to root canals. A great endodontist can make it work with almost any file system—whether it’s a cheap $10 set off eBay (I wouldn’t recommend it, one time file broke right off at the hub at first insert) or a top-tier German-made set. That doesn’t mean I’d ever choose the $10 eBay files as my go-to, but the point is: skill matters more than the brand name on the package.
Why I Prefer Austenitic (Non-Heat-Treated) Files
After experimenting with many systems, I’ve found myself consistently favoring non-heat-treated (austenitic, or “stiffer”) files as my main system. Here’s why:
Faster treatment times – My procedures take nearly half the time compared to using flexible, heat-treated “noodle” files.
Accurate cone fit – With austenitic files, my master cone fit is predictable and reliable.
That said, heat-treated files do have their place. They’re more flexible, more forgiving, and useful when negotiating tricky canals to full working length. But their reduced cutting efficiency means:
It takes longer to instrument.
Cone fits become less accurate.
The Problem with Heat-Treated Files
How many times have you thought you instrumented to 21 mm, only to find your cone short at 19 mm (or less) on the radiograph?
Here’s why: if you instrument with, say, a 30/.04 heat-treated file, in theory you should have 0.3 mm at your working length. But because heat-treated files don’t cut efficiently, the actual apical size ends up smaller.
The result?
You second-guess your working length and start over-instrumenting.
Heat-treated files are flexible and as it’s in the canal files unwind and elongate
Cause bleeding (from overinstrumenting)
Gets skinnier and doesn’t open up the canal enough (and not the best cone fit).
You increase the risk of postoperative pain.
Or worse—you try to “gain” length by injecting more sealer, which leads to additional complications.
My teeth hurts just by looking at this one.
Yikes
Final Thought
In my opinion, efficiency and accuracy matter more than fancy technology or expensive gadgets. For me, stiff (austenitic) files provide both. Heat-treated files are a helpful tool—but they shouldn’t be the main weapon of choice if your goal is faster, more predictable root canal treatments.
