Mohamed Medhat AL-Sobahy, Dina Mohamed EL-Beshlawy And Hany Mahmoud Omar .,

ABSTRACT
Objective: The Aim Of The Present Study Was To Assess The Effect Of Using Three Different Voxel Sizes On The Accuracy Of Planmeca Promax 3D Mid CBCT Images In Detection Of Simulated External Root Resorption Defects In Mandibular Single Rooted Teeth.

Materials and Methods: Fifty Five Recently Extracted Human Mandibular Incisor Teeth Were Collected And Disinfected, Five Hundred Defects Were Prepared On Their Different Root Surfaces Simulating External Root Resorption Lesions, The Teeth Were Positioned Inside The Sockets Of A Dry Mandible And Were Imaged By The Planmeca Promax 3D Mid CBCT Scanner Using 0.4, 0.2 And 0.15 Voxel Sizes, The Images Were Evaluated Independently By Two Radiologists.

Results: The Results Of Both Observers Showed That CBCT High Resolution Protocol Has Higher Sensitivity And Accuracy Than Normal And Low Resolution Protocol, Moreover, The CBCT Low Resolution Protocol Showed The Least Sensitivity And Accuracy Among All Protocols. Additionally, According To Both Observers, There Was A High Statistically Significance Difference In The Detectability Of All Simulated Defects Using CBCT Low Resolution Protocol (voxel Size 0.4) And Both Normal (voxel Size 0.2) And High (voxel Size 0.15) Resolution Protocols (P <0.001 HS), While There Was No Statistical Significance Difference In Detectability Of The Defects Using CBCT Normal And High Resolution Protocols (P > 0.05 NS). Conclusion: Considering The Studied CBCT Scanner, The Normal And High Resolution Protocols (voxel Sizes 0.2 And 0.15 Respectively) Showed A Similar High Efficacy In Detection Of Simulated External Root Resorption Defects In Mandibular Single Rooted Teeth And Their Usefulness Was Superior To That Of The Low Resolution Protocol (voxel Size 0.4). However, According To The ALARA Principle, The Normal Resolution Protocol Should Be The Scan Of Choice As It Delivers Less Radiation Exposure To The Patient.