Efficacy of Four Irrigation Techniques Put Under the Microscope
The first ever in vitro study to compare the efficacy of 4 irrigation techniques, namely, needle, ultrasonic, EndoActivator and photon-induced photoacoustic streaming (PIPS) in removing calcium hydroxide from the root canal and isthmus was conducted. Calcium hydroxide has been widely used as an intracanal medicament between visits in endodontic therapy, and prior to final root canal obturation, the chemicals within the canal root must be completely removed, or the residues can affect the outcome of the obturation.
The findings revealed no difference in volume reduction of calcium hydroxide among the four irrigation groups in the coronal and middle thirds of the root canal. However, ultrasonic and PIPS irrigation are found to have higher capacity than EndoActivator and needle irrigation in eliminating calcium hydroxide from the isthmus regions of the root canal of maxillary premolars.
The study also showed that none of the irrigation techniques is capable of entirely removing calcium hydroxide from the whole canal system. It comes to the conclusion that more effective methods need to be developed for cleaning the apical portion of the root canal.
Li D, Jiang SM, Yin X, Chang JWW, Ke J & Zhang C. “Efficacy of Needle, Ultrasonic, and EndoActivator Irrigation and Phonton-Induced Photoacoustic Streaming in Removing Calcium Hydroxide from the Main Canal and Isthumus: An In Vitro Micro-Computed Tomography and Scanning Electron Microscopy Study”, Photomedicine and Laser Surgery, Vol.33, No.6, pp.330 – 337.