1. EXPOSURE AND TECHNIQUE ERRORS
DA 105

2. Dental Radiography Questions
What film exposure and technique errors may be observed on dental radiographs?
What horizontal and vertical angulation errors may be observed on dental radiographs?
What is the proper film placement for bite-wing radiographs?

3. Dental Radiography Exposure and Technique Errors Film exposure errors
Technique errors (periapical films)
Technique errors (bite-wing films)
Miscellaneous technique errors

4. Exposure and Technique Errors
Purpose
To describe film exposure problems and periapical, bite-wing, and miscellaneous technique errors

5. Film Exposure Errors Exposure Problems
Unexposed film
Film exposed to light
Time and Exposure Factor Problems
Overexposed film
Underexposed film

6. Unexposed Film Appearance The film appears clear Cause
Failure to turn on the x-ray machine
Electrical failure
Malfunction of the x-ray machine
Correction
Make certain the x-ray machine is turned on and listen for the audible exposure signal

7. An unexposed film appears clear

8. Film Exposed to Light Appearance Cause Correction
The film appears black
Cause
The film was exposed to white light
Correction
Do not unwrap in a room with white light
Check the darkroom for light leaks
Turn off all lights in the darkroom except the safelight

9. A film exposed to light appears black

10. Overexposed Film Appearance Cause Correction Film appears dark
Excessive exposure time, kilovoltage, milliamperage
Correction
Check settings and reduce as needed before exposing film

11. An overexposed film appears dark

12. Underexposed Film Appearance Cause Correction The film appears light
The film was underexposed
Correction
Check the exposure time, kilovoltage, and milliamperage settings on the x-ray machine before exposing the film

13. An underexposed film appears light

14. Technique Errors (Periapical Films)
Film Placement Problems
Correct film placement
Incorrect film placement
Absence of apical structures
Dropped film corner
Angulation Problems
Incorrect horizontal angulation
Incorrect vertical angulation
PID Alignment Problems
Cone-cut with Film Holder
Cone-cut without Film Holder

15. Correct Film Placement
Each periapical film must be positioned in a certain way to show specific teeth and related anatomic structures
The edge of the periapical film must be placed parallel to the incisal or occlusal surfaces of the teeth and extend 1/8th inch beyond the incisal or occlusal surfaces

16. Correct periapical film placement demonstrates the entire tooth, including the apex and surrounding structures

17. Absence of Apical Structures
Haring (p. 276) (Fig. 20-6)
Appearance
No apices appear on the film
Cause
The film was not positioned in the patient’s mouth to cover the apical regions of the teeth
Correction
Make certain no more than 1/8th inch of the film edge extends beyond the incisal-occlusal surfaces of the teeth

18. Improper film placement; no apices appear on this film

19. Dropped Film Corner Appearance
The occlusal plane appears tipped or tilted
Cause
The edge of the film was not placed parallel to the incisal-occlusal surfaces of the teeth
Correction
Make certain the edge of the film is placed parallel to the incisal-occlusal surfaces of the teeth

20.   Improper film placement; a dropped film corner is seen when the edge of the film is not placed parallel to the incisal or occlusal surfaces of the teeth

21. Incorrect Horizontal Angulation
Appearance
Overlapped contacts
Cause
The central ray was not directed through interproximal spaces
Correction
Direct the x-ray beam through interproximal regions

22. Incorrect horizontal angulation results in overlapped contact areas

23. Incorrect Vertical Angulation
Foreshortened images
Appearance
Short teeth with blunted roots
Cause
Excessive vertical angulation
Correction
Do not use excessive vertical angulation with the bisecting technique

24. If the vertical angulation is too steep, the image of the tooth on the film is shorter than the actual tooth; the images are foreshortened

25. Incorrect Vertical Angulation
Elongated images
Appearance
Long, distorted teeth
Cause
The vertical angulation was insufficient
Correction
Use adequate vertical angulation with the bisecting technique

26. If the vertical angulation is too flat, the image of the tooth on the film is longer than the actual tooth; the images are elongated

27. PID Alignment Problems
Cone-cut with film holder
Appearance
A clear area appears on the film
Cause
The PID was not properly aligned with the periapical film holder
Correction
Make certain the x-ray beam is centered over the film

28. A cone-cut is seen when the PID is not properly aligned with the periapical film-holding device

29. PID Alignment Problems
Cone-cut without film holder
Appearance
A clear area appears on the film
Cause
The PID was not directed at the center of the film
Correction
Make certain the x-ray beam is centered over the film

30. A cone-cut appears as a curved unexposed (clear) area on a radiograph

31. Technique Errors (Bite-Wing Films)
Film Placement Problems
Correct film placement
Incorrect film placement
Angulation Problems
Incorrect horizontal angulation
Incorrect vertical angulation
PID Alignment Problems
Cone-cut with film holder
Cone-cut without film holder

32. Correct Film Placement
Premolar bite-wing
The resulting film shows both the maxillary and mandibular premolars and distal contact areas of both canines
Molar bite-wing
The resulting film shows both the maxillary and mandibular molars

33. Correct film placement for the premolar bite-wing

34. Correct film placement for the molar bite-wing

35. Incorrect Film Placement
Premolar bite-wing
Appearance
Distal surfaces of the canines are not visible on the film
Cause
The bite-wing film was positioned too far posteriorly in the mouth
Correction
Make certain the anterior edge of the bite-wing film is positioned at the midline of the mandibular canine

36. Incorrect film placement for the premolar bite-wing

37. Incorrect Film Placement
Molar bite-wing
Appearance
Third molar regions are not visible on film
Cause
The bite-wing film was positioned too far anteriorly in the mouth
Correction
Make certain the anterior edge of the bite-wing film is positioned at the midline of the mandibular second premolar

38. Incorrect film placement for the molar bite-wing

39. Incorrect Horizontal Angulation
Appearance
Overlapped contacts on the film
Cause
The central ray was not directed through the interproximal spaces
Correction
Direct the x-ray beam through the interproximal spaces

40. Overlapped interproximal contacts result from incorrect horizontal angulation

41. Incorrect Vertical Angulation
Appearance
Images appear distorted on the film
Cause
The vertical angulation was incorrect
Correction
Always use a +10-degree vertical angulation with the bite-wing technique

42. Incorrect vertical angulation causes the images to appear distorted

43. Cone-Cut With Film Holder
Appearance
A clear area appears on the film
Cause
The PID was not properly aligned with the film holder
Correction
Make certain the PID and the aiming ring are aligned

44. A, A cone-cut is seen when the PID is not properly aligned with the bite-wing film-holding device. B, A cone-cut can also be produced with rectangular collimation; the PID is not properly aligned with the bite-wing film-holding device

45. Cone-Cut Without Film Holder
Appearance
A clear area appears on the film
Cause
The PID was not directed at the center of the film
Correction
Make certain the x-ray beam is centered over the film

46. A cone-cut appears as a curved unexposed (clear) area on a radiograph

47. Miscellaneous Technique Errors
Film Bending
Film Creasing
Phalangioma
Double Exposure
Movement
Reversed Film

48. Film Bending Appearance Cause Correction
Images appear stretched and distorted
Cause
The film was bent excessively
Correction
Check film placement before exposure

49. A bent film appears distorted

50. Film Creasing Appearance Cause Correction
A thin radiolucent line appears on the film
Cause
The film was creased
Correction
Do not bend or crease the film excessively

51. A film crease appears as a thin radiolucent line

52. Phalangioma Appearance Cause Correction Haring (p. 282) (Fig. 20-23)
The patient’s finger appears on the film
Cause
The patient’s finger was positioned in front of the film
Correction
Make certain the patient’s finger is placed behind the film

53. This film demonstrates a phalangioma; the bones of a patients finger appear on the film

54. Double Exposure Appearance Cause Correction
A double image appears on the film
Cause
The film was exposed twice in the patient’s mouth
Correction
Always separate exposed and unexposed films

55. This film demonstrates a double exposure

56. Movement Cause Correction Appearance Blurred images appear on the film
The patient moved during exposure of the film
Correction
Instruct the patient to remain still while the film is being exposed

57. Movement results in a blurred image

58. Reversed Film Appearance
Light images with a herringbone pattern appear on the film
Cause
The film was placed backward in the mouth and then exposed
Correction
Always place the white side of the film adjacent to the teeth

59. A reversed film appears light with a herringbone (or tire-track) pattern. The tire-track pattern is seen on the lead-foil backing within the film packet

60. EXPOSURE AND TECHNIQUE ERRORS
DIAGNOSTIC DENTAL RADIOGRAPH:
1.FILM EXPOSURE ERRORS:
EXPOSURE PROBLEMS
a) Unexposed film
APPEARANCE
CAUSE
CORRECTION
b) Film exposed to light
TIME AND EXPOSURE FACTOR PROBLEMS
a) Overexposed film
b) Underexposed film

61. TECHNIQUE ERRORS(PERIAPICAL FILMS)
FILM PLACEMENT PROBLEMS
ANGULATION PROBLEMS
PID ALIGNMENT PROBLEMS

62. FILM PLACEMENT PROBLEMS
ERROR
APPEARANCE
CAUSE
CORRECTION
CORRECT FILM PLACEMENT
INCORRECT FILM PLACEMENT
a) ABSENCE OF APICAL STRUCTURES
b) DROPPED FILM CORNER

63. ANGULATION PROBLEMS APPEARANCE CAUSE CORRECTION ERROR
INCORRECT HORIZONTAL ANGULATION
INCORRECT VERTICAL ANGULATION
a) FORESHORTENED IMAGE
b) ELONGATED IMAGE

64. PID ALIGNMENT PROBLEMS
ERROR
APPEARANCE
CAUSE
CORRECTION
CONE-CUT WITH FILM HOLDER
CONE-CUT WITHOUT FILM HOLDER

65. TECHNIQUE ERRORS(BITE-WING FILMS)
FILM PLACEMENT PROBLEMS
ANGULATION PROBLEMS
PID ALIGNMENT PROBLEMS

66. FILM PLACEMENT PROBLEMS
ERROR
CORRECT FILM PLACEMENT
1)PREMOLAR BITE-WING
2)MOLAR BITE-WING
INCORRECT FILM PLACEMENT

67. INCORRECT HORIZONTAL ANGULATION INCORRECT VERTICAL ANGULATION
ANGULATION PROBLEMS
ERROR
APPEARANCE
CAUSE
CORRECTION
INCORRECT HORIZONTAL ANGULATION
INCORRECT VERTICAL ANGULATION

68. PID ALIGNMENT PROBLEMS
ERROR
APPEARANCE
CAUSE
CORRECTION
CONE-CUT WITH FILM HOLDER
CONE-CUT WITHOUT FILM HOLDER

69. MISCELLANEOUS TECHNIQUE ERRORS
APPEARANCE
CAUSE
CORRECTION
1.FILM BENDING
2.FILM CREASING
3.PHALANGIOMA
4.DOUBLE EXPOSURE
5.MOVEMENT
6.REVERSED FILM