Graduation Date

Summer 8-9-2019

Document Type


Degree Name

Master of Science (MS)


Medical Sciences Interdepartmental Area

First Advisor

David H. Shaw, PhD


Using micro computed tomography (micro-CT) as a reference standard, the purpose of this investigation was to evaluate the influences of bone mineral loss and radiographic contrast in digital periapical (PA) film and cone-beam computed tomography (CBCT). Seven dog and human mandibles were sectioned, followed by modification via cortical bone drilling to create 248 lesions and/or trabecular bone acid demineralization to create 96 coronal slice pairs. Pretreatment and post-treatment radiographs (PA, CBCT, and/or micro-CT) were taken for lesion rating/perception in addition to two-dimensional (area) and three-dimensional (volumetric) measurements of 50 drilling lesions and 20 coronal slice pairs. 4-7% bone mineral loss is needed for radiographic perception of cortical bone drilling lesions (rating ≥3), and at least 17.34% bone mineral loss is needed for trabecular bone acid demineralization perception. Radiographic contrast indices were difficult to ascertain and may be related to regional differences and lesion anatomical location. This study suggests that even though %BML is a major factor in radiographic lesion perception, additional factors of regional and anatomical contrast influence lesion rating. With a limited sample size, further testing is needed to investigate cortical bone lesion perception differences between dog and human mandibles, to quantify radiographic contrast, and to identify more precise trabecular bone demineralization thresholds.

Available for download on Sunday, June 27, 2021