Aim- The purpose of this study was to study the amount of apically extruded debris and axis modification and centering ability using CBCT in relatively curved root canals with Wave One and One Shape single file systems. Method -Forty extracted human adult teeth with curvatures were selected. Experimental study groups were divided as Group I-WaveOne (n=20) and Group II-One Shape (n=20). To evaluate the axis modification and centering ability, pre and post- operative views were analyzed in longitudinal and axial sections which were taken using RVG and CBCT respectively. For evaluating the amount of debris extrusion, the difference between the pre-instrumentation and post-instrumentation weight of Eppendorf tubes were calculated. For inter- group comparison, ANOVA followed by Post- Hoc test were used. Results- WaveOne and One Shape single file systems showed statistically non- significant modification of root canal axis and centering ability. WaveOne single file system non-significantly generated more debris as compared to One Shape. Conclusion- It was concluded that WaveOne single file reciprocating systems demonstrated better centering ability as compared to OneShape single file rotary systems in curved root canals. KEYWORDS: centering ability; axis modification; root curvature