Accuracy of Linear Measurements Made on Cone Beam Computed Tomography Scans at Different Magnifications
AbstractObjective: This study aimed to evaluate the accuracy of linear measurements made on CBCT (New Tom VGi) scans with different image magnifications.
Methods: Forty-two titanium pins were inserted into seven dry sheep mandibles. Lengths of the pins were measured using a digital caliper with 0.01 mm readability, and the mandibles were radiographed using a CBCT unit. After reconstruction of CBCT images, three experienced radiologists measured the length and diameter of titanium pins at100%, 200% and 400% magnifications. Accuracy of measurements was analyzed using descriptive statistics and one-way analysis of variance (ANOVA) P<0.05 was considered statistically significant. Inter observer reliability was calculated using the intra class correlation coefficient (ICC) test.
Results: The mean differences of linear measurements from the actual lengths of pins were 0.1960 mm, 0.2143 mm and 0.2047 mm at 100%, 200% and 400% magnifications, respectively (P>0.05). The mean differences of linear measurements from the actual diameters of pins were 0.2206 mm, 0.2063 mm and 0.1984 mm at 100%, 200% and 400% magnifications, respectively (P>0.05). Inter observer reliability of pin length measurements was estimated to be0.285, 0.707 and 0.479 at 100%, 200% and 400%magnifications, respectively. Inter observer reliability of pin diameter measurements was 0 .078, 0.469 and 0.587 at 100%, 200% and 400%magnifications, respectively.
Conclusion: Based on the results, image magnification does not affect the accuracy of linear measurements made on CBCT scans. Inter observer reliability of pin length measurements was good at 200% magnification, while it was below the acceptable range at other magnifications. For measurement of pin diameters, this index was below the acceptable range at all magnifications.
2- Al-Ekrish AA, Ekram M.A comparative study of the accuracy and reliability of multi detector computed tomography and cone beam computed tomography in the assessment of dental implant site dimensions. . Dentomaxillofac Radiol2011;40:67-75
3-Sheikhi M ,Ghorbanizadeh S, Abdinian M, Goroohi H, Badrian H . Accuracy of linear measurement of Galileos Cone beam Computed tomography in normal and different head position. Int J Dent 2012 July;16:
4-Zeigler CM , Woertcher R, Breif J, Hassfeld S. Clinical indications for digital volume tomography in oral and maxillofacial surgery. Dentomaxillofac Radiol 2002 Mar;31(2):126-130.
5- Guerrero ME, Jacobs R, Loubele M, Schutyser F, Suetens P, Van Steenberghe D. State-Of-The-Art on cone beam CT imaging for preoperative planning of implant placement. Clin Oral Investig 2006 Mar;10(1): 1-7.
6- Hellak A, Schmidt N, Schauseil M, Stein S, Drechsler T, Korbmacher-Steiner HM. Influence of Invisalign treatment with interproximal enamel reduction (IER) on bone volume for adult crowding: a retrospective three-dimensional cone beam computed tomography study. BMC Oral Health. 2016 Sep 1;16(1):83.
7- Yamamato K , Ueno K, Seo K, Shinohara D. Development of dento-maxillofacial cone-beam x-ray computed tomography system. Orthod craniofacial Res 2003; 6 supple:160-162
8- Yepes J, Al-Sabbagh M; Use of Cone-Beam Computed Tomography in Early Detection of Implant Failure. Dent Clin N Am; 59 (2015): 41–56
9- Cavalcanti MG, Rocha SS, Vannier MW. Craniofacial measurements based on 3D-CTvolume rendering: implications for clinical applications. Dentomaxillofac Radiol 2004; 33: 170–176.
10-Guerrero ME, Jacobs R, Loubele M, Schutyser F, Suetens P, van Steenberghe D. State-of the-art on cone beam CT imaging for preoperative planning of implant placement. Clin Oral Investig 2006; 10: 1–7.
11- John GP, Joy TE, Mathew J, Kumar VR. Fundamentals of cone beam computed tomography for a prosthodontist. The Journal of the Indian Prosthodontic Society. 2015 Jan;15(1):8 –13.
12- Tyndall DA, Rathore S. Cone-beam CT diagnostic applications: caries, periodontal bone assessment, and endodontic applications. Dental Clinics of North America. 2008 Oct 31;52(4):825-41.
13- Sherrard JF , Rossouw P.E ,Byron W. Accuracy and reliability of tooth and root lengths measured on cone-beam computed tomographs. American Journal of orthodontics and dentofacial orthopedic 2010Apr;137(4 supple):s100-8.
14- Moshfeghi M, Amin Tavakoli M, Tavakoli Hosseini E, Tavakoli Hosseini A, Tavakoli Hosseini I. Analysis of linear measurement accuracy obtained by cone beamcomputed tomography (CBCT‑NewTom VG). Dental Research Journal2012 ;9: (Suppl 1):S57-62
15- Danya Hashem D, Brown J E, Patel S, Mannocci F, Donaldson A N, Watson T F, Banerjee A. An In Vitro Comparison of the Accuracy of Measurements Obtained from High- and Low-resolution Cone-beam Computed Tomography Scans. J Endod 2013;39:394–397
16- Nikneshan S, Hamidi Aval S, Bakhshalian S, Shahab S, Mohammadpour M, Sarikhani S. Accuracy of linear measurement using cone-beam computed tomography at different reconstruction angles. Imaging Science in Dentistry 2014; 44: 257-62
17- Boas FE, Fleischmann D. Evaluation of two iterative techniques for reducing metal artifacts in computed tomography. Radiology. 2011 Jun;259(3):894-902.
18- Kositbowornchai S, Sikram S, Nuansakul R,Thinkhamrop B. Root fracture detection on digital images: effect of the zoom function. Dent Traumatol 2003;19:154-159.
19-Kositbowornchai S, Basiw M, Promwang Y, Moragorn H, Sooksuntisakooncha N. Accuracy of diagnosing occlusal caries using enhanced digital images. Dentomaxillofacial Radiology (2004) 33: 236–240
20- Morais J, Sakakura CE, Lofferdo LCM, Scaf G. Accuracy of zoomed digital image in the detection of periodontal bone defect: in vitro study. Dentomaxillofacial Radiology (2006) 35, 139–142
21- Rangel FA, Maal TJ, Bronkhorst EM, Breuning KH, Schols JG, Bergé SJ, Kuijpers-Jagtman AM. Accuracy and reliability of a novel method for fusion of digital dental casts and cone beam computed tomography scans. PloS one. 2013 Mar 20;8(3):e59130.
22- Ganguly R, Ruprecht A, Vincent S, Hellstein J, Timmons S and Qian F. Accuracy of linear measurement in the Galileos cone beam computed tomography under simulated clinical conditions. Dentomaxillofacial Radiology. 2011;40:299-305
23- Fatemitabar SA, Nikgoo A. Multichannel computed tomography versus cone-beam computed tomography : linear accuracy of in vitro measurements of the maxilla for implant placement. Int J Oral Maxillofacial Implants. 2010 May;25(3): 499-505.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.