The placement of calcium hydroxide as intracanal medication is an important step in the management of endodontic infections and inflammation. The present study was conducted to assess efficacy of these different irrigation devices in removal of CH in teeth with simulated internal resorption cavities. Materials & Methods: 60 single-rooted mandibular premolars were decoronated and prepared using the ProTaper Gold system up to F5. 10 specimens were served as group I – negative control. 10 specimens were served as group II – positive control. The remaining specimens were divided into 4 groups, where NaOCl and EDTA were activated using PUI, XP-endo, EA, and E1 for 1 minute. The remnants of CH were scored as 0- Free of CH debris, 1- Less than half was filled with CH debris, 2- More than half was filled with debris, and 3- Completely filled with debris Results: None of the tested groups were able to remove complete CH paste from simulated internal resorption cavities. PUI and XP-endo file showed superior and effective results as compared to all other groups. EndoActivator (EA) showed similar results to XP-endo but significant difference with PUI whereas Endo-Irrigator Plus (EI) showed the least amount of CH removal (P < 0.05). Score 0, 1, 2 and 3 in group I was as 100%, in group II was 100%, in group III was 50%, 38%, 12%, in group IV was 55%, 10%, 27% and 8%, in group V was 24%, 16%, 40% and 20%, and in group VI was 6%, 32%, 42% and 21% respectively. The difference was significant (P< 0.05). Conclusion: In artificial internal resorption cavities, CH could not be entirely eliminated by any irrigation method. In this case, PUI outperformed all other irrigation tools, while XP-endo eliminated CH just as well as PUI did—but better than EA and EI plus.