Alveolar bone measurements in magnetic resonance imaging compared with cone beam computed tomography: a pilot, ex-vivo study

Objectives: To compare alveolar bone height and width measurements from zero-echo-time MRI (ZTE-MRI) and cone beam CT (CBCT), in human specimens. Material and methods: Twenty posterior edentulous sites in human cadaver specimens were imaged with CBCT and ZTE-MRI. Bone height and width at 1, 3, 5, 7 and 9 mm from the top of the alveolar ridge was measured by two trained observers in cross-sections of a site where an implant was to be planned. Twenty percent of the sample was measured in duplicate to assess method error and intra-observer reproducibility (ICC). The differences between CBCT and ZTE-MRI measurements were compared (t-test). Results: Inter- and intra-observer reproducibility was >0.90. The method error (average between observers) for bone height was 0.45 mm and 0.39 mm, and for bone width (average) was 0.52 mm and 0.80 mm (CBCT and ZTE-MRI, respectively). The majority of the bone measurement differences were statistically insignificant, except bone width measurements at 5 mm (p ≤.05 for both observers). Mean measurement differences were not larger than the method error. Conclusion: ZTE-MRI is not significantly different from CBCT when comparing measurements of alveolar bone height and width.