Errors of dental radiography

errors of dental radiography

1. Errors of dental radiography Prepared by : WRia S. Rasheed

2. Technique & Projection errors . Exposure errors . Processing errors. contents:

3. Films with errors should be avoided due to the following reasons: Retake will lead to: Expose the patient to unnecessary radiation. Waste film & time (money). Interfere with accurate interpretation and diagnosis.

4. Causes of faulty radiograph The majority of the errors produced can be categorized into three groups: Technique & Projection errors. Exposure errors. Processing errors.

5. Technique & Projection errors: a. Patient preparation error: b. Film placment artifact: Blurred image Radiopaque artifact Reversed film Double image Apices cut off Dot artifact Dropped film corner Crown not shown Black line Area of interest not shown Distortion

6. c. Projection errors: Incorrect vertical angulation. Incorrect horizontal angulation PID alignment artifact Incorrect vertical angulation

7. Technique & Projection errors a. Patient preparation error Radiopaque artifact Dental appliances, body piercings, jewelry & eye glasses left in the mouth during exposure will appear as radiopaque artifact superimposed over the dental image. Correction : all this items should be removed before placing of the film.

8. Technique & Projection errors a. Patient preparation error Blurred image Movement of the film, patient or X-ray tube head during exposure will result in a blurred image. Correction : the operator should explain for the patient & remind him to remain motionless during exposure.

9. Technique & Projection errors b. Film placment artifact Double image When an exposed film is re-exposed the resulting film will have 2 superimposed images

10. Technique & Projection errors b. Film placment artifact Reversed film Low density with herring bone, tire-track or dotted pattern, as a result of directing the X-ray through the lead foil side of the film back.

11. Technique & Projection errors b. Film placement artifact Dot artifact The identification dot produce a circular radiolucent artifact on the final radiograph. This may interfere with interpretation of the apical areas of the teeth.

12. Technique & Projection errors b. Film placment artifact Apices cut off Occur when the film is not positioned apically enough to record the entire tooth.

13. Crown not shown Technique & Projection errors b. Film placment artifact There is no enough film extending occlusally .

14. Technique & Projection errors b. Film placment artifact Dropped film corner The film edge is not placed parallel to the occlusal surface of the teeth.

15. Technique & Projection errors b. Film placment artifact Area of interest not shown This is the result of not placing the film to cover all the teeth in the area of interest and not centralizing the film over the area of interest.

16. Technique & Projection errors b. Film placment artifact Black line Due to excessive bending of the film prior to its placement inside the patient’s mouth (pressure causes ionization of silver halide upon processing will be darker).

17. Technique & Projection errors b. Film placment artifact Distortion Due to bending of the film to eliminate the patient’s discomfort specially in lower premolar area and upper central incisors. normal distortion

18. Technique & Projection errors c. Projection errors Incorrect vertical angulation It will lead to: Elongated image due to insufficient v. angulation ( too flat), or Shortened image due to excessive v. angulation ( too steep)

19. Technique & Projection errors c. Projection errors

20. Technique & Projection errors c. Projection errors

21. Technique & Projection errors c. Projection errors Incorrect horizontal angulation (overlap) Is the appearance of the interproximal surfaces of the adjacent teeth over each other. This is due to improper H.A .

22. Technique & Projection errors c. Projection errors

23. Technique & Projection errors c. Projection errors PID alignment artifact If the PID is misaligned and the x-ray is not centered over the film, a partial image is seen on the resultant radiograph, this partial image is called cone-cut. It appear as a clear area with curved outline.

24. II. Exposure errors. Blank image. Low density image. High density image. Image with high and low contrast .

25. Exposure errors Blank image A film that didn’t receive radiation will have no image and will appear clear.

26. Errors in machine operation : Excessive milliamperage Excessive kilovoltage Excessive time Film_ source distance too short processing errors: Accidental exposure to light Inadequate fixation High developer temp. High developer conc. High developing time High density image

27. Low density (faint) image ( too light) Exposure errors Causes : Old developer solution Low developer temp. Low developing time Low developer conc. Incomplete fixation

28. III. Processing errors Chemical errors: Light image. Dark image. Blank image. Reticulation. Black spot or patch. White spot or patch. Yellowish brown discoloration. Film Handling errors: Writing lines Developer cut off Fixer cut off Finger nail artifact Smudge. Scratched film Static electricity

29. Processing errors Chemical errors Reticulation When the film subjected to a sudden temperature changes between the developer and water. Appear as cracked film.

30. Processing errors Chemical errors Black spot or patch Developer contamination before immersion into the developer solution.

31. White spot or patch Processing errors Chemical errors Contamination with fixer before processing

32. Yellowish brown discoloration Processing errors Chemical errors Exhausted solution or insufficient rinsing

33. Processing errors Film Handling errors Writing lines Appear on the radiograph due to writing on the film packet with ballpoint pen or lead pencil. It may appear black or white. Finger nail artifact Black or whit crescent shape mark due to rough handling of the film.

34. Developer cut off Processing errors Film Handling errors A straight white border . The film may not be completely immersed in the developer solution.

35. Fixer cut off Processing errors Film Handling errors A straight black border. The film may not be completely immersed in the fixer solution.

36. Processing errors Film Handling errors Smudge (finger print) When the film touched by fingers contaminated with developer or fixer

37. Processing errors Film Handling errors Scratched film White lines appear on the film due to careless handling of the film.

38. Processing errors Film Handling errors Static electricity Thin black branching lines Occurs when two surfaces are rubbed together against each other vigorously, this creates an electric charges with visible light emitted which is capable of exposing the x-ray film, thus leading to ionization of AgBr crystals at this area. Occur most frequently during periods of low humidity

39. Metallic partial denture Blurred

40. Reverse image Apices cut off

41. Dropped corner Distortion

42. Elongation Horizontal overlap Double image

43. Low denisty Static electricity

44. White spot or patch Yellowish brown discoloration

45. Reverse image Cone-cut Developer cut off