Mohamed Gamal Elbanna, Hossam Kandil, Iman Dakhli And Ahmed Hossam Eldien,

ABSTRACT
Aim Of Study: To Validate The Reliability Of Cone Beam Computed Tomography (CBCT) Corrected HU Using The Correlation Equation Of The CBCT Gray Values, With True Hounsfield Units (HU) Derived From Multislice Computed Tomography (MSCT) As A Gold Standard. Methods: The Study Was Performed On Human Dry Mandibles Acquired From The Department Of Anatomy, Faculty Of Medicine, Cairo University. Soft Tissue Simulation In The Form Of Full Mandibular Coverage Was Done By Adapting Eight Sheets Of Softened Pink Wax Approximately 12mm Thickness. Mandibles Were Scanned By Both Cone Beam Computed Tomography (CBCT) And Multislice CT Followed By Importing The Dicom Files From Both CBCT And CT Into Outsider Third Party Software (On-Demand Software) Which Empowers Our Measurements.

Results: Pearson Correlation Showed A Weak Correlation Between Voxel Gray Values In CBCT With HU In MSCT In All Selected Areas. Conclusion: The Corrected HU Derived From Voxel Gray Values Obtained From CBCT Revealed A Weak To Fair Correlation With HU Obtained From MSCT. CBCT Readings On Measuring Bone Density Were Not Reliable.