One file system I dislike using is reciprocating files. Why? Because they take too long and, more importantly, they push infected dentin deeper into the canal rather than cleaning it out, as continuous rotation files do. Think of it like drilling a tunnel: if you move the drill back and forth, the debris stays packed inside the flutes and gets forced deeper instead of being carried out. Is that an efficient way to drill? I don’t think so.

Left is the reciprocating file motion showing that the rotation motion is pushing infected dentin into the root canal space while right image is showing continuous motion is pulling out of the root canal space.

This has direct correlation to root canal success. The whole point of endodontic treatment is to eliminate infection and remove compromised pulp. If reciprocating motion packs infected dentin and pulp deeper into the canal, are we truly addressing the root cause? Again, I don’t think so.

Another issue is the complexity of reciprocating file systems. Sales reps tell me with a straight face about settings like 130° forward and 50° backward (or worse telling me to try different angles), expecting dentists to adopt them easily. Life is complicated enough—why add confusing angles and degrees into the mix?

For my practice, I only use continuous (forward) rotation with rotary files. Companies market new “optimal glide path” or similar functions, promising that the motor will do the work for you. But in reality, these features still have a learning curve, and you still have to put in effort to get down the canal. So now I’m being asked to invest in expensive motors, learn new settings, and adjust my technique—all for a process that’s supposed to be simpler? Most dentists already dread root canals; overly complicated products only make the experience worse and push many toward implants instead.

But here’s the truth implant companies don’t emphasize: implants fail too. Yes, some cases require extraction and implants, but they should not be the default option. When implants fail, you often need bone grafting—which takes months to heal—and sometimes raising the vertical bone height is extremely difficult. Patients are left without teeth in those areas, often relying on retainers until integration is complete.

I’m not saying implants should never be used, but root canals remain a highly effective treatment that deserves to be preserved and promoted, rather than undermined by unnecessarily complex tools.

Another frequently asked question is what setting do I use for my handpiece for rotary files. Whether is retreat, regular root canals, I only have one setting 500 rpm, 1.0 NcM or 100 gcm (depending on how its showing on the unit). I can explain more about these in later posts but with right filing motion you really don’t need to tinker with settings too much and still do root canals very efficiently.