Laser-How Does it Work?

Access into the pulpal chamber may be performed with the Er:YAG, Nd:YAG or ER,CR:YSGG laser, which provides decontamination and removal of bacterial debris and pulpal tissue to yield a cleaner chamber (figure a). 

Laser-assisted canal irrigation requires canal preparation to an apical preparation ISO 25/30 with a taper of 0.04 or 0.06 NaOCl is utilized within the chamber and canals during instrumentation both as pulpal tissue dissolvent and to lubricate the files within the canal (figure b).

Photo-activation of the irrigant within the canal system using the laser with a 0.4/17 or 0.6/17 mm tip assists in removal of the debris created by the files. The tip of the laser is placed into the chamber and the solution activated with the laser as 40 mJ at 10 Hz with an average power of only 0.5 W for 20 seconds (figure c).

It is unnecessary to place the laser tip into the canal, as activation of the solution within the chamber transmits down the irrigant in the canals to the apical aspect of the roots. Laser activation may also be performed with 17% EDTA solution alternated with NaOCl, giving the benefit of EDTA chelation effect to open canal anatomy so that the next round of NaOCl can reach more pulpal tissue (figure 5,6).