Marc Albert Louis , Ihab El Sayed Hassanein And Mohamed Mokhtar Nagy,

ABSTRACT
Aim Of The Study: The Aim Of This Study Was To Compare The Cleaning Efficiencybetween Two Different Filesystems With Different Motions, Reciprocating Single Filesystem WaveOne And Rotation With Protaper Universal Files, And Assessment Of The File Surfaces ChangesMethodology: 52 Freshly Extracted Human Firstmolars Were Decoronated Using A Disc And Split Into Mesial And Distal Roots. Divided Into Two Groups; GRP I: 26 Mesial Roots ProTaper Universal Files S1-F2, GRP II: 26 Mesial Roots. WaveOne Files Primary. Instruments Were Examined For Defects In Apical And Middle Third Under SEM Prior Their Usage At Magnification200X. Pulp Space Preparation Was Done, According To Manufacturer Instruction In Combination With Irrigation With 5.25% NaOCl. Each Of These Instruments Were Subjected To Simulated Clinical Use (1-6). Mesial Roots Were Split And Assessed At The Apical Middle And Cervical Parts Under SEM And Stereomicroscope For Smear Layer And Debris Respectively. SEM Observations Were Done After The Sixth Use, For Defects At The Apical And Middle Third, And Photomicrographs Were Taken.

Results: Either At The Cervical, Middle Or At Apical Levels, There Was No Statistically Significantdifference Between Mean Debris Score Of The Two Systems. Comparing The Root Levels Either With WaveOne Or ProTaper; Apical Level Showed The Highest Mean Debris Score With Statistically Significantdifference From Cervical Level And Non-statistically Significantdifference From Middle Level. Conclusion: Among The Motions, Both Rotation And Reciprocation Have Similar Cleaning Efficiency;the Apical One Third Of The Canal Is Most Liable To More Debris And Smear Layer And Brand New Files Sufered From Manufacturing Defects.