effective, even when the SAF is intimately adapted to and touching the canal walls. This phenomenon may be useful in cleaning the walls of immature teeth. In such wide canals, the SAF is likely to scrub the canal walls without removing a layer of dentin. In single-rooted teeth, SAF with a 2.0 mm diameter can be used, while in immature roots of molars, 1.5 mm SAF may be useful.

The continuous ßow of sodium hypochlorite without any pressure in the apical direction may also be both useful and safe when treating immature teeth. If syringe and needle irrigation is applied, the pressure generated by the ßow from the needle oriÞce may be sufÞcient to push sodium hypochlorite beyond the apex. A special risk exists when the periapical tissue contains a cavity of an abscess or a bay cyst. Such pressure is not present when the SAF is used (see above) [39, 56, 57]. The sodium hypochlorite is brought into the canal with continuous ßow and with continuous agitation. The combination of a continuous supply of fresh sodium hypochlorite with the scrubbing effect on the walls may provide a unique method to effectively clean the walls of those wide canals without reducing the thickness of their dentin walls. Because many of the canals of immature teeth are rather wide, in several cases, microscopically estimating the cleaning effectiveness of these canals by the SAF system is possible, and the results are impressive.

The use of the SAF for this unique purpose is based on sporadic clinical observations. To the best of our knowledge, no study on this possible use of the SAF has been published thus far, and further exploration of this idea is warranted.

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