Aim: to evaluate canal cleanliness after using manual dynamic activation, passive ultrasonic irrigation and photoactivated disinfection in comparison with conventional needle irrigation, using scanning electron microscopy
Methods: Sixty single rooted human premolars with nearly straight single canal were collected, the crowns of all teeth were removed near the level of cementoenamel junction to obtain approximately 15 ±1 mm uniform root lengths. After instrumentaion with ProTaper Next files up to X4 (40/06), roots were randomly divided into 4 equal groups (n=15) according to the method of final irrigation activation. Group I: Conventional needle and syringe irrigation. Group II: Manual dynamic activation. Group III: passive ultrasonic irrigation. Group IV: photoactivated disinfection. Canal cleanliness was evaluated with SEM using different magnification (X350- X1000).
Results: Group III had the best cleanliness of the root canal while Group I had the worst cleanliness, there were statistical significant differences between Group I versus Groups II and III and between Group III and Group IV (P ≤ 0.05). Regardless the irrigation activation method, the coronal level showed significantly less amount of smear layer and remaining debris than the apical level.
Conclusions: None of the tested final irrigation activation methods resulted in completely clean canal wall.