Mohamed Magdy, Salma El Ashry, Hossam Tewfik And Ahmed Ghobashy .,

ABSTRACT


Introduction: Root Canal Treatment Yields A High Success Rate Reaching Above 90%. However, For Several Reasons, Including The Persistence Of Apical Periodontitis, Failed Cases Require Non-surgical Retreatment.

Aim: To Evaluate The Efficacy Of ProTaper Universal Retreatment Files Versus Mtwo Retreatment Files In Removing Gutta-percha Sealed In Curved Root Canals Using Two Types Of Sealers

Materials and Methods: A Total Of 40 Extracted Mandibular Molars With Mesio-buccal Canals Exhibiting Between 20 And 35 Degrees Of Curvature Were Mounted On Plastic Blocks. After Coronal Access Preparation, Root Canal Cleaning & Shaping Was Carried Out Using A ProTaper Universal System And Obturated Using Gutta-percha With 2 Different Sealers (zinc Oxide Eugenol Sealer, Epoxy- Resin Sealer). The Samples Were Pre-operatively Scanned Using Cone Beam Computed Tomography (CBCT). After 7 Days, Retreatment Procedures Were Performed Using Both Systems. The Retreatment Procedure Was Considered To Be Complete When The Last File Reached The Root Apex. Samples Were Postoperatively Scanned Using CBCT. The Samples Were Longitudinally Sectioned And Then Split Into Two Halves And Examined Under A Stereomicroscope, Followed By Photography And Assessment Using Image Analysis Software. The Percentage Of Remaining Filling Material In The Coronal, Middle And Apical Thirds Of The Canal Was Calculated In Mm�.

Results: Significant Differences Were Observed Between The Both Systems Regardless Of The Sealer Type. Either AH Plus Or TubliSeal Sealer, ProTaper System Showed Significantly Less Remaining Filling Material Than Mtwo System. A Difference Was Found Between Apical And Cervical Levels In ProTaper System And AH Plus Group, While In Mtwo System And AH Plus Group, A Difference Was Found Between Apical Versus Middle And Cervical Levels. Conclusion: Retrieval Of Root Canal Filling Material During The Retreatment Procedure Is Best Performed Using ProTaper Universal Retreatment Files. Caution Should Be Taken While Using The ProTaper Universal System In Order Not To Jeopardize The Remaining Dentin Thickness Of The Root Canal.