title: Contrast curves of five different intraoral X-ray sensors: a technical note.
abstract: OBJECTIVE
  The aim of this article is to compare the contrast and resolution properties of five different sensors using a known technical target.
  
  
  METHODS
  Stripe patterns with defined amounts of line pairs per mm (2.5-20 LP/mm) were recorded using five commercial digital sensors. Image data were analyzed using ImageJ and MatLab to calculate different contrast curves using logistic regression.
  
  
  RESULTS
  The Dexis Platinum Sensor reached a calculated 10% contrast at 29.52 LP/mm. The Duerr VistaRay 6 Sensor reached a 10% contrast at 9.9 LP/mm. The 10% contrast was found at 18.8 LP/mm for the Duerr VistaRay 7. The Sirona Xios+ Sensor reached a calculated 10% contrast at 13.9 LP/mm. The Sirona Fullsize charge-coupled device (CCD) Sensor exhibited 10% contrast at 10.3 LP/mm.
  
  
  CONCLUSIONS
  The contrast transfer function assessment used in the study confirmed that the spatial frequency at 10% contrast was much lower than the theoretical resolution computed from the pixel size.
authors.affiliation: Department of Oral Surgery, University Medical Center, Mainz, Germany. bruellmd@uni-mainz.de
authors.forename: Dan Dominik
authors.initials: DD
authors.lastname: Brüllmann
authors.forename: Benedikt
authors.initials: B
authors.lastname: Kempkes
authors.forename: Bernd
authors.initials: B
authors.lastname: d'Hoedt
authors.forename: Ralf
authors.initials: R
authors.lastname: Schulze
mesh_terms: D016015:Logistic Models; D019252:Radiography, Dental, Digital / Q000295:instrumentation* / Q000379:methods