Advances in Clinical and Experimental Medicine
2015, vol. 24, nr 6, November-December, p. 1071–1077
Publication type: original article
Evaluating Maxilla Bone Quality Through Clinical Investigation of Voxel Grey Scale Values from Cone-Beam Computed Tomography for Dental Use
1 Department of Dental Prosthetics, Medical University of Lodz, Poland
Background. During the study the relative bone density thickness in maxilla was evaluated in 20 patients.
Objectives. The aim of the study was to investigate relative bone density in maxilla by means of voxel value measurements.
Material and Methods. The study comprised of 20 patients in whom cone beam computed tomography scans were made for diagnostic purposes. The horizontal scans of the maxilla were used for analysis. The measurements of density of both cortical plates and trabecular bone were taken in interdental spaces. To eliminate negative values a modified grey scale was introduced in which radiological density of the air was determined as “0”. For every patient relative bone density was calculated separately for anterior and posterior maxilla.
Results. Mean values of relative radiological density for cortical plates and trabecular bone were 0.849 for palatal cortical plate, 0.8978 for vestibular cortical plate and 0.5988 for trabecular bone in anterior maxilla with standard deviation (SD) 0.0931 – 0.0971 – 0.1091 respectively. In posterior maxilla the mean values were 0.5274 for palatal cortical plate, 0.6047 for vestibular cortical plate and 0.3307 for trabecular bone with SD 0.1635 – 0.1515 – 0.126 respectively. The statistically significant difference (p < 0.001) was found for radiological density of dental alveolus in anterior and posterior maxilla.
Conclusion. The mean of radiological densities of vestibular cortical plate is higher than that of palatal cortical plate. The mean radiological density of trabecular bone is ×2 lower than the mean radiological density of vestibular cortical plate in posterior region and ×1.5 lower in anterior region of the maxilla. The clinical use of CBCT radiological bone density measurement tool with modified grey scale voxel values creates possibility to evaluate the relative bone density of dental alveolus.
cone-beam computed tomography, grey levels, bone density
- Schulze R, Heil U, Bruellmann DD, Dranischnikow E, Schwanecke U, Schoemer E: Artefacts in CBCT: a review. Dentomaxillofac Radiol 2011, 40, 265–273.
- De Vos W, Casselman J, Swennen RJ: Cone-beam computerized tomography (CBCT) imaging of the oral and maxillofacial region: A systematic review of the literature. Int J Oral Maxillofac Surg 2009, 38, 609–625.
- Ibrahim N, Parsa A, Hassan B, van der Stelt P, Aartman IHA, Wismeijer D: Accuracy of trabecular bone microstructural measurement at planned dental implant sites using cone-beam CT datasets. Clin Oral Implants Res 2013, 00, 1–5. Epub ahead of print.
- Hounsfield GN: Nobel lecture, December 8, 1979. Computed medical imaging. J Radiol 1980, 61, 459–468.
- Hounsfield GN: Computerized transverse axial scanning (tomography): Part 1. Description of the system. Br J Radiol 1973, 46, 1016–1022.
- Schreiber JJ, Anderson PA, Rosas HG, Buchholz AL, Au AG: Hounsfield units for assessing bone mineral density and strength: a tool for osteoporosis management. J Bone Joint Surg Am 2011, 93, 1057–1063.
- Turkyilmaz I, Ozan O, Yilmaz B, Ersoy AE: Determination of bone quality of 372 implant recipient sites using Hounsfield unit from computerized tomography: a clinical study. Clin Implant Dent Relat Res 2008, 10, 238–244.
- Aranyarachkul P, Caruso J, Gantes B, Schulz E, Riggs M, Dus I: Bone density assessments of dental implant sites: 2. Quantitative cone–beam computerized tomography. Int J Oral Maxillofac Implants 2005, 20, 416–424.
- Shapurian T, Damoulis PD, Reiser GM, Griffin TJ, Rand WM: Quantitative evaluation of bone density using the Hounsfield index. Int J Oral Maxillofac Implants 2006, 21, 290–297.
- Silva IM, Freitas DQ, Ambrosano GM, Bóscolo FN, Almeida SM: Bone density: comparative evaluation of Hounsfield units in multislice and cone-beam computed tompgraphy. Braz Oral Res 2012, 26, 550–556.
- Holweg-Majert B, Metzger MC, Kummer T, Schulze D: Morphometric analysis – Cone beam computed tomography to predict bone quality and quantity. J Craniomaxillofac Surg 2011, 39, 330–334.
- Holweg-Majert B, Pautke C, Deppe H, Metzger MC, Wagner K, Schulze D: Qualitative and Quantitative Evaluation of Bony Structures Based on DICOM Dataset. J Oral Maxillofac Surg 2011, 69, 2763–2770.
- Mah P, Reeves TE, McDavid WD: Deriving Hounsfield units using grey levels in cone beam computed tomography. Dentomaxillofac Radiol 2010, 39, 323–335.
- Reeves TE, Mah P, McDavid WD: Deriving Hounsfield units using grey levels in cone beam CT: a clinical application. Dentomaxillofac Radiol 2012, 41, 500–508.
- Parsa A, Ibrahim N, Hassan B, Motroni A, van der Stelt P, Wismeijer D: Reliability of voxel grey values in cone beam computed tomography for preoperative implant planning assessment. Int J Oral Maxillofac Implants 2012, 27, 1438–1442.
- Nomura Y, Watanabe H, Honda E, Kurabayashi T: Reliability of voxel values from cone-beam computed tomography for dental use in evaluating bone mineral density. Clin Oral Implants Res 2010, 21, 558–562.
- Zioupos P, Cook RB, Hutchinson JR: Some basic relationships between density values in cancellous cortical bone. J Biomech 2008, 41, 1961–1968.
- Skaug Sande EP, Trægde Martinsen AC, Olaug Hole E, Olerud HM: Interphantom and interscanner variations for Hounsfield units – establishment of reference values for HU in a commercial QA phantom. Phys Med Biol 2010, 55, 5123–5135.
- Birnbaum BA, Hindman N, Lee J, Baab JS: Multidetector row CT attenuation measurements: Assessment of intraand interscanner variability with an anthropomorphic body CT phantom. Radiology 2007, 242, 109–119.
- Lagravére MO, Fang Y, Carey J, Toogood RW, Packota GV, Major PW: Density conversion factor determined using a cone-beam computed tomography unit NewTom QR-DVT 9000. Dentomaxillofac Radiol 2006, 35, 407–409.