title: Influence of CBCT enhancement filters on diagnosis of vertical root fractures: a simulation study in endodontically treated teeth with and without intracanal posts.
abstract: OBJECTIVE
  To evaluate the influence of CBCT enhancement filters on the diagnosis of vertical root fractures (VRFs) in teeth with and without metal posts.
  
  
  METHODS
  The crowns of 40 uniradicular human teeth were removed and all roots were prepared. 20 teeth were randomly selected, and VRFs were induced using a universal testing machine. The i-CAT (Imaging Sciences International, Hatfield, PA) CBCT was used to scan teeth with and without intracanal metal posts using the following parameters: 0.2 voxel size, 8 × 8-cm scan size and acquisition time of 26.9 s. Images were evaluated by three observers with and without the use of the following filters: S9, smooth, smooth 3 × 3, sharpen, sharpen-mild and sharpen 3 × 3.
  
  
  RESULTS
  Intra- and interobserver agreement ranged from poor to moderate. Images with and without CBCT filters did not show significant differences regarding the area under the receiver operating characteristic curve, as well as sensitivity (p > 0.05). As for accuracy, the sharpen-mild filter was superior to the sharpen (p = 0.03), but these filters did not differ from all others. For specificity, S9, smooth and original images were superior to sharpen (p < 0.01). Results for teeth without posts differed from those for teeth with metal posts in all cases (p < 0.05).
  
  
  CONCLUSIONS
  The use of enhancement filters in CBCT images has no influence on the diagnosis of VRFs in teeth with metal posts, and their use is not justified.
authors: 1 Division of Oral Radiology, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, São Paulo, Brazil.
authors: L M
authors: LM
authors: Ferreira
authors: M A P G
authors: MA
authors: Visconti
authors: H A
authors: HA
authors: Nascimento
authors: R R
authors: RR
authors: Dallemolle
authors: G M
authors: GM
authors: Ambrosano
authors: D Q
authors: DQ
authors: Freitas
mesh_terms: D054893:Cone-Beam Computed Tomography / Q000295:instrumentation*; D006801:Humans; D066298:In Vitro Techniques; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D012387:Root Canal Filling Materials; D014082:Tooth Fractures / Q000000981:diagnostic imaging*; D014092:Tooth Root / Q000000981:diagnostic imaging*; D019553:Tooth, Nonvital / Q000000981:diagnostic imaging*
chemical_list: D012387:Root Canal Filling Materials
keywords: cone beam computed tomography; radiographic image enhancement; vertical root fracture