title: Influence of the artefact reduction algorithm of Picasso Trio CBCT system on the diagnosis of vertical root fractures in teeth with metal posts.
abstract: OBJECTIVE
  To assess the influence of the artefact reduction algorithm (AR) available on the Picasso Trio 3D(®) imaging system (Vatech, Hwaseong, Republic of Korea) on image quality [greyscale values, contrast-to-noise ratio (CNR) and artefact formation] and diagnosis of vertical root fractures (VRFs) in the teeth with intracanal metal posts.
  
  
  METHODS
  30 uniradicular teeth had their crowns removed and their roots endodontically treated to receive intracanal metal posts. In 20 teeth, both complete (n = 10) and incomplete (n = 10) VRFs were created. Each tooth was scanned twice, with and without AR activation. The mean and variation of greyscale values, as well as CNR, were calculated for all images. Subsequently, an evaluator compared the amount of artefact (cupping, white streaks and dark bands) in all images. Five evaluators rated for VRF presence using a five-point scale.
  
  
  RESULTS
  Mean greyscale values and CNR were significantly decreased in images acquired with the AR. The usage of the algorithm promoted an overall reduction of image artefacts. Regarding the diagnosis of complete and incomplete VRFs, the use of the AR had an overall negative impact on specificity and accuracy.
  
  
  CONCLUSIONS
  While indeed reducing artefact formation, the use of the AR, instead of improving the impact on the diagnosis of VRFs in teeth with intracanal metal posts, had a negative impact on the diagnosis.
authors.affiliation: 1 Oral Radiology Area, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: I S Q
authors.initials: IS
authors.lastname: Bezerra
authors.affiliation: 1 Oral Radiology Area, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: F S
authors.initials: FS
authors.lastname: Neves
authors.affiliation: 1 Oral Radiology Area, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: T V
authors.initials: TV
authors.lastname: Vasconcelos
authors.affiliation: 2 Department of Community Dentistry, Dental School of Piracicaba, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: G M B
authors.initials: GM
authors.lastname: Ambrosano
authors.affiliation: 1 Oral Radiology Area, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: D Q
authors.initials: DQ
authors.lastname: Freitas
mesh_terms: D000465:Algorithms; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D008670:Metals; D011176:Post and Core Technique / Q000295:instrumentation*; D014082:Tooth Fractures / Q000000981:diagnostic imaging*; D014092:Tooth Root / Q000000981:diagnostic imaging*; D019553:Tooth, Nonvital / Q000000981:diagnostic imaging*
chemical_list: D008670:Metals
keywords: artefacts; cone beam computed tomography; diagnosis; tooth fractures