title: In vitro comparison of contemporary radiographic imaging techniques for the measurement of inter-radicular width.
abstract: OBJECTIVE
  To assess the reliability of inter-radicular measurements taken using dental pantomograms (DPT), long cone periapical radiographs (LCPA) and cone bean computed tomography (CBCT).
  
  
  METHODS
  A typodont simulating a hypodontia patient undergoing fixed appliance treatment was used. LCPAs, DPT, I-CAT and Accuitomo CBCT images were taken and the distances between the edentulous spans were measured at the midpoint of the roots and the cemento-enamel junctions (CEJ) of adjacent teeth. The results of each modality were compared to each other to the actual inter-radicular space.
  
  
  RESULTS
  The DPT overestimated inter-radicular widths by 2 mm or more [mean: 2.48; 95% confidence interval (CI): -1.09 to 6.05 mm]. The LCPA overestimated the inter-radicular widths by 1.5 mm with a 95% CI of -0.095 to 4.03 mm. The mean differences between gold standard (model) and Accuitomo was 0.57 mm (95% CI: -0.37 to 1.51 mm) for the root mean and 0.22 mm (95% CI: -0.52 to 0.96 mm) for the CEJ. This was similar to the differences between the model and I-CAT where the inter-radicular root mean difference was 0.38 mm (95% CI: -0.38 to 1.14 mm) and the CEJ mean difference was 0.21 mm (95% CI: -0.50 to 0.92 mm).
  
  
  CONCLUSIONS
  The CBCT overestimated the root distance by 0.48 mm and the CEJ width by 0.22 mm, which is clinically irrelevant for implant placement. The DPT overestimated inter-radicular width by 2 mm and the LCPA by 1.5 mm and this difference may put roots of adjacent teeth at risk during implant placement.
authors.affiliation: a Department of Orthodontics , Guy's and St Thomas NHS Foundation Trust , London , UK.
authors.forename: Bouthayna
authors.initials: B
authors.lastname: Al-Tamimi
authors.affiliation: b Unit of Dental & Maxillofacial Radiological Imaging , King's College London Dental Institute at Guy's Hospital , London , UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Davies
authors.affiliation: c Imperial Clinical Trials Unit, School of Public Health , Imperial College London, Faculty of Medicine , UK.
authors.forename: Francesca
authors.initials: F
authors.lastname: Fiorentino
authors.affiliation: a Department of Orthodontics , Guy's and St Thomas NHS Foundation Trust , London , UK.
authors.forename: Dirk
authors.initials: D
authors.lastname: Bister
mesh_terms: D000848:Anodontia / Q000000981:diagnostic imaging*; D054893:Cone-Beam Computed Tomography; D006801:Humans; D019252:Radiography, Dental, Digital; D015203:Reproducibility of Results; D014070:Tooth; D014092:Tooth Root
keywords: Inter-radicular width measurements; Radiographic technique