title: Detection of vertical root fractures by conventional radiographic examination and cone beam computed tomography - an in vitro analysis.
abstract: OBJECTIVE
  This study compared the ability of conventional radiographic and cone beam computed tomography (CBCT) examinations to detect vertical root fractures (VRF) in teeth with or without root canal treatment and metallic posts. Furthermore, the influence of using different voxel sizes from CBCT images was assessed.
  
  
  METHODS
  Sixty single-rooted human teeth were randomly divided into two groups: experimental and control. Twenty teeth were endodontically prepared and obturated with gutta-percha, twenty had a metallic postcemented after the filling, and twenty had no preparation. The teeth from the experimental group were fractured. All teeth were radiographed with three different horizontal angles, and after, CBCT images were acquired following three protocols in which the variation was the voxel resolution (0.4, 0.3, and 0.2 mm). Three calibrated examiners assessed the images.
  
  
  RESULTS
  Chi-squared test showed no statistical difference among the images in detecting VRFs. The results of the diagnostic performance tests presented similar ability to detect VRFs when conventional radiographic examination was compared with 0.2 and 0.3-voxel CBCTs scans, in roots without endodontic treatment and metallic post. Moreover, specificity, sensitivity, and accuracy findings were similar for both 0.2 and 0.3-voxel resolution scans for teeth that are not root filled. However, it was observed that in teeth with root canal treatment and a post, the accuracy was higher when 0.2-mm voxel resolution was used.
  
  
  CONCLUSIONS
  The radiographic examination with horizontal angle variation should be encouraged as the first complementary approach to assess the presence of VRFs. If conventional imaging is not capable to provide adequate information, CBCT can be indicated if a root fracture is strongly suspected. The root condition should then guide the voxel resolution choice, selecting 0.3-voxel for not root filled teeth and 0.2-voxel for teeth with filling and/or a post.
authors.affiliation: Oral Radiology Division, Department of Surgery and Orthopedics, Dental School, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Priscila Fernanda
authors.initials: PF
authors.lastname: da Silveira
authors.forename: Mariana Boessio
authors.initials: MB
authors.lastname: Vizzotto
authors.forename: Gabriela Salatino
authors.initials: GS
authors.lastname: Liedke
authors.forename: Heraldo Luis Dias
authors.initials: HL
authors.lastname: da Silveira
authors.forename: Francisco
authors.initials: F
authors.lastname: Montagner
authors.forename: Heloísa Emília Dias
authors.initials: HE
authors.lastname: da Silveira
mesh_terms: D019540:Area Under Curve; D054893:Cone-Beam Computed Tomography / Q000706:statistics & numerical data*; D003722:Dental Alloys / Q000737:chemistry; D006171:Gutta-Percha / Q000627:therapeutic use; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data; D011176:Post and Core Technique; D012372:ROC Curve; D011861:Radiography, Dental / Q000706:statistics & numerical data; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000379:methods; D012390:Root Canal Therapy; D012680:Sensitivity and Specificity; D014082:Tooth Fractures / Q000000981:diagnostic imaging*; D014092:Tooth Root / Q000293:injuries*; D019553:Tooth, Nonvital / Q000000981:diagnostic imaging
chemical_list: D003722:Dental Alloys; D012387:Root Canal Filling Materials; D006171:Gutta-Percha