title: Imaging the Cemento-Enamel Junction Using a 20-MHz Ultrasonic Transducer.
abstract: The cemento-enamel junction (CEJ), which is the intersection between enamel and cementum, is an important landmark in the diagnosis of periodontal disease. Pulse-echo ultrasound was used to image the CEJs of six porcine lower central incisors with a single 20-MHz transducer. A notch was longitudinally created on the enamel as a stable marker, from which the CEJ was measured. Data were acquired along the tooth's axis at 0.4-mm intervals. Time-distance data were bandpass-filtered to enhance signal-to-noise ratio and record density was increased fourfold to 0.1-mm spacing by a frequency-distance interpolation scheme. Reflections from the CEJ were unambiguously identified along with those from enamel, dentin and cementum. The notch-CEJ distances measured by the ultrasound and micro-computed tomography methods correlated strongly (r = 0.996, p < 0.05) and were in good agreement with the 95% lines of agreement between -0.49 and 0.17 mm, as statistically determined by Bland-Altman analysis. The results indicate the potential of ultrasound to be a reliable and non-ionizing technique to image the CEJ.
authors.affiliation: School of Dentistry, University of Alberta, Edmonton, Alberta, Canada; Department of Radiology and Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Kim-Cuong T
authors.initials: KC
authors.lastname: Nguyen
authors.affiliation: Department of Radiology and Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada. Electronic address: lawrence.le@ualberta.ca.
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Le
authors.affiliation: School of Dentistry, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Neelambar R
authors.initials: NR
authors.lastname: Kaipatur
authors.affiliation: School of Dentistry, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Major
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D023421:Models, Animal; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D013552:Swine; D019237:Tooth Cervix / Q000000981:diagnostic imaging*; D014159:Transducers; D014463:Ultrasonography; D055114:X-Ray Microtomography
keywords: Cemento-enamel junction; Cementum; Enamel; Gingiva; Micro-computed tomography; Periodontal disease; Ultrasound