CBCT-based bone quality assessment: are Hounsfield units applicable?

TY - JOUR

T1 - CBCT-based bone quality assessment

T2 - are Hounsfield units applicable?

AU - Pauwels, R.

AU - Jacobs, R.

AU - Singer, S. R.

AU - Mupparapu, M.

PY - 2015/1

Y1 - 2015/1

N2 - CBCT is a widely applied imaging modality in dentistry. It enables the visualization of high-contrast structures of the oral region (bone, teeth, air cavities) at a high resolution. CBCT is now commonly used for the assessment of bone quality, primarily for pre-operative implant planning. Traditionally, bone quality parameters and classifications were primarily based on bone density, which could be estimated through the use of Hounsfield units derived from multidetector CT (MDCT) data sets. However, there are crucial differences between MDCT and CBCT, which complicates the use of quantitative gray values (GVs) for the latter. From experimental as well as clinical research, it can be seen that great variability of GVs can exist on CBCT images owing to various reasons that are inherently associated with this technique (i.e. the limited field size, relatively high amount of scattered radiation and limitations of currently applied reconstruction algorithms). Although attempts have been made to correct for GV variability, it can be postulated that the quantitative use of GVs in CBCT should be generally avoided at this time. In addition, recent research and clinical findings have shifted the paradigm of bone quality from a density-based analysis to a structural evaluation of the bone. The ever-improving image quality of CBCT allows it to display trabecular bone patterns, indicating that it may be possible to apply structural analysis methods that are commonly used in micro-CT and histology.

AB - CBCT is a widely applied imaging modality in dentistry. It enables the visualization of high-contrast structures of the oral region (bone, teeth, air cavities) at a high resolution. CBCT is now commonly used for the assessment of bone quality, primarily for pre-operative implant planning. Traditionally, bone quality parameters and classifications were primarily based on bone density, which could be estimated through the use of Hounsfield units derived from multidetector CT (MDCT) data sets. However, there are crucial differences between MDCT and CBCT, which complicates the use of quantitative gray values (GVs) for the latter. From experimental as well as clinical research, it can be seen that great variability of GVs can exist on CBCT images owing to various reasons that are inherently associated with this technique (i.e. the limited field size, relatively high amount of scattered radiation and limitations of currently applied reconstruction algorithms). Although attempts have been made to correct for GV variability, it can be postulated that the quantitative use of GVs in CBCT should be generally avoided at this time. In addition, recent research and clinical findings have shifted the paradigm of bone quality from a density-based analysis to a structural evaluation of the bone. The ever-improving image quality of CBCT allows it to display trabecular bone patterns, indicating that it may be possible to apply structural analysis methods that are commonly used in micro-CT and histology.

KW - cone-beam computed tomography

KW - Hounsfield units

KW - bone quality

KW - dental implants

KW - BEAM COMPUTED-TOMOGRAPHY

KW - DENTAL IMPLANT SITES

KW - CORTICAL BONE

KW - CANCELLOUS BONE

KW - DENSITY ASSESSMENTS

KW - PERIAPICAL LESIONS

KW - FRACTAL DIMENSION

KW - VOXEL VALUES

KW - GREY LEVELS

KW - CT

U2 - 10.1259/dmfr.20140238

DO - 10.1259/dmfr.20140238

M3 - Review

SN - 0250-832X

VL - 44

JO - Dentomaxillofacial Radiology

JF - Dentomaxillofacial Radiology

IS - 1

M1 - 20140238

ER -