Sir, I read with interest the concerns of Dr Vivekananda Pai about using sodium hypochlorite for endodontic irrigation.1 I decided many years ago to stop squirting anything into a root canal even with so-called 'safe tipped' syringes.

A method I find seems to work very well is to dry the canal, place a dry paper point into the canal, then with a pair of closed tweezers transfer (with a gloved hand underneath to catch any drops) a small drop of NaOCl into the pulp chamber and then to allow capillary action to move this into the canal. Further drops can be added until the paper point is soaked and the pulp chamber full. To remove - yet further paper points until dry - then it's probably safe to use any water irrigation for debris removal, but I favour ultrasonic irrigation.

I don't know if this has been tested in the lab, but intuitively it seems to be as effective as any for introducing NaOCl and again intuitively seems to be a lot safer.