Deborah Queiroz Freitas1, Rocharles Cavalcante Fontenele1, Eduarda Helena Leandro Nascimento, Taruska Ventorini Vasconcelos2, Marcel Noujeim3. 1. 1 Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas , Limeira , Brazil. 2. 2 Division of Oral Radiology, School of Dentistry, Federal University of Bahia , Salvador , Brazil. 3. 3 Department of Comprehensive Dentistry, Division of Oral and Maxillofacial Radiology, University of Texas Health Science Center at San Antonio , San Antonio, TX , United States.
Abstract
AIM: To evaluate the influence of kilovoltage (kVp) and metal artifact reduction tool (MAR) on the magnitude of cone beam CT (CBCT) artifacts. METHODS: A titanium and zirconia implants were inserted alternately in a posterior region of a mandible. CBCT exams were acquired with ProMax 3D (Planmeca Oy, Helsinki, Finland) and Picasso Trio machines (Vatech, Hwaseong, South Korea) using 70 kVp, 80 kVp and 90 kVp with and without MAR activation. The other exposure factors remained fixed at 5mA, field of view 80 × 50 mm and voxel 0.20 mm. The scans were performed before and after the insertion of the implants. Regions of interest were determined in different distances from the artifact production area (15, 25 and 35 mm) in an axial image, in which standard deviation (SD) of grayscale values was measured and contrast-to-noise ratio (CNR) was calculated. Analysis of variance was used to compare the data. RESULTS: Overall, in cases where the artifact was pronounced, MAR was efficient in reducing SD values. MAR also improved the CNR of ProMax images, but did not affect the Picasso images. Additionally, the higher was the kVp, the lower was the SD value and the higher was the CNR in both machines. CONCLUSION: In both machines, increasing kVp and MAR are effective in decreasing the CBCT artifacts in all their magnitude when they are pronounced. Therefore, the professionals should choose one of those options or even both considering the purpose of the CBCT imaging and radiation dose for the patient.
AIM: To evaluate the influence of kilovoltage (kVp) and metal artifact reduction tool (MAR) on the magnitude of cone beam CT (CBCT) artifacts. METHODS: A titanium and zirconia implants were inserted alternately in a posterior region of a mandible. CBCT exams were acquired with ProMax 3D (Planmeca Oy, Helsinki, Finland) and Picasso Trio machines (Vatech, Hwaseong, South Korea) using 70 kVp, 80 kVp and 90 kVp with and without MAR activation. The other exposure factors remained fixed at 5mA, field of view 80 × 50 mm and voxel 0.20 mm. The scans were performed before and after the insertion of the implants. Regions of interest were determined in different distances from the artifact production area (15, 25 and 35 mm) in an axial image, in which standard deviation (SD) of grayscale values was measured and contrast-to-noise ratio (CNR) was calculated. Analysis of variance was used to compare the data. RESULTS: Overall, in cases where the artifact was pronounced, MAR was efficient in reducing SD values. MAR also improved the CNR of ProMax images, but did not affect the Picasso images. Additionally, the higher was the kVp, the lower was the SD value and the higher was the CNR in both machines. CONCLUSION: In both machines, increasing kVp and MAR are effective in decreasing the CBCT artifacts in all their magnitude when they are pronounced. Therefore, the professionals should choose one of those options or even both considering the purpose of the CBCT imaging and radiation dose for the patient.
Authors: R Schulze; U Heil; D Gross; D D Bruellmann; E Dranischnikow; U Schwanecke; E Schoemer Journal: Dentomaxillofac Radiol Date: 2011-07 Impact factor: 2.419
Authors: Sergio Lins de-Azevedo-Vaz; Priscila Dias Peyneau; Laura Ricardina Ramirez-Sotelo; Karla de Faria Vasconcelos; Paulo Sérgio Flores Campos; Francisco Haiter-Neto Journal: Oral Surg Oral Med Oral Pathol Oral Radiol Date: 2016-01-28
Authors: Luciano Augusto Cano Martins; Polyane Mazucatto Queiroz; Yuri Nejaim; Karla de Faria Vasconcelos; Francisco Carlos Groppo; Francisco Haiter-Neto Journal: Dentomaxillofac Radiol Date: 2020-03-16 Impact factor: 2.419