title: Measurement accuracy of marginal bone level in digital radiographs with and without color coding.
abstract: OBJECTIVE
  New radiographic techniques have made it possible to color-code intra-oral digital radiographs. The purpose of the present study was to compare the accuracy and precision of marginal bone level measurements in digital radiographs with and without color coding.
  
  
  METHODS
  Periapical digital radiographs of 21 patients were processed with and without a color-coding algorithm. The patients had periodontal surgery immediately after exposure of radiographs, and vertical distances from the cemento-enamel junction (CEJ) to the most apical part of the marginal bone were measured clinically. The measured values were considered as a reference standard and subtracted from the corresponding radiographic vertical distance. Seven observers contributed to the radiographic measurements under the same viewing conditions.
  
  
  RESULTS
  No statistically significant differences were found between absolute differences of vertical distances obtained from radiographs and their corresponding reference standards in the two types of radiograph. Intra- and inter-observer variability was not significant.
  
  
  CONCLUSIONS
  Color-coded digital radiographs did not provide a more favorable accuracy when assessing marginal alveolar bone levels than black-and-white radiographs and thus did not improve measurement of such levels.
authors: Department of Oral and Maxillofacial Radiology, Peking University School and Hospital of Stomatology, Beijing, China. kqgang@bjmu.edu.cn
authors: Gang
authors: G
authors: Li
authors: Per-Erik
authors: PE
authors: Engström
authors: Ulf
authors: U
authors: Welander
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000473:pathology; D000704:Analysis of Variance; D003116:Color; D006801:Humans; D016014:Linear Models; D008875:Middle Aged; D011856:Radiographic Image Enhancement / Q000379:methods*; D019252:Radiography, Dental, Digital / Q000379:methods*; D014963:X-Ray Intensifying Screens