Evaluation of a mathematical model for digital image enhancement

Hassem Geha, Ibrahim Nasseh, Marcel Noujeim

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


Objective: The purpose of this study is to compare the detected number of holes on a stepwedge on images resulting from the application of the 5th degree polynomial model compared to the images resulting from the application of linear enhancement. Material and Methods: A 10-step aluminum step wedge with holes randomly drilled on each step was exposed with three different kVp and five exposure times per kVp on a Schick33®sensor. The images were enhanced by brightness/contrast adjustment, histogram equalization and with the 5th degree polynomial model and compared to the original non-enhanced images by six observers in two separate readings. Results: There was no significant difference between the readers and between the first and second reading. There was a significant three-factor interaction among Method, Exposure time, and kVp in detecting holes. The overall pattern was: “Poly” results in the highest counts, “Original” in the lowest counts, with “B/C” and “Equalized” intermediate. Conclusion: The 5th degree polynomial model showed more holes when compared to the other modalities.

Original languageEnglish (US)
Article numberA1
Pages (from-to)292-296
Number of pages5
JournalOpen Dentistry Journal
StatePublished - 2015


  • Contrast
  • Digital imaging
  • Histogram
  • Image enhancement

ASJC Scopus subject areas

  • General Dentistry


Dive into the research topics of 'Evaluation of a mathematical model for digital image enhancement'. Together they form a unique fingerprint.

Cite this