Introduction: Successful endodontic therapy focuses on completely eliminating microorganisms, which is the main etiology for pulpitis and apical periodontitis. The ideal endodontic irrigant should be strong enough to dissolve intracanal necrotic/vital tissue and to eliminate bacteria and gentle enough on the extra radicular tissues; it also should be non-toxic, non-antigenic and non-carcinogenic. Aim: This study aimed to compare the smear layer removal using saline, sodium hypo chlorite (NaOCl) + Saline + ethylenediaminetetraacetic acid (EDTA), and quaternary ammonium silane irrigants (QAS). Material and methods: This study was conducted on 63 freshly extracted maxillary canines. Specimens were randomly divided into 3 main groups, A1, A2, and A3 (n=42), according to the type of irrigant used (saline group, 2.25%, saline, + EDTA 17%, and quaternary ammonium silane QAS group, respectively). Each main group was further sub-divided into three subgroups according to the method of activation B0, B1, B2 (n=14) (no activation group, Manual Dynamic Activation (MDA) group. Each group was evaluated by Scanning electron microscopy (SEM). ANOVA was followed by Duncan multiple range tests (DMRTs) to compare between treatment groups or corresponding post hoc for nonparametric Results showed significant differences between different groups. The difference between the activation methods was statistically significant (in the cervical third, middle third, and apical third). The highest mean value was recorded in sodium hypochlorite (NOCl), followed by QAS, with the lowest value recorded in saline. The difference between groups wasstatistically significant in the cervical, middle and apical root thirds. There is a statistically significant difference between groups using no activation, MDA and overall (regardless of the activation technique)