Dr. Sami El Agha Faculty of Dentistry, Al - Azhar University, Gaza lama El banna Radiographic techniques

1. RADIOGRAPHIC TECHNIQUES
DR SAMY I AL-AGHA
A.PROFESSOR OF RADIOLOGY
AL-AZHAR –GAZA UNIVERCITY

2. RADIOGRAPHIC TECHNIQUES
CLASSIFICATION
A-Periapical
B-Bite-wing
C-Occlusal

4. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
1-BISECTING ANGLE TECNIQUE
A-Patient,s position
For maxillary teeth>>>ala tragus line is parallel
to floor
For mandibular teeth>>>line from tragus to
corner of mouth is parallel to floor

6. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
B-Film placement:
Tube side of the film packetis towards the tube.
The film(short dimension) is parallel to occlusal
plane(For anterior region)
The film (long dimension) is parallel to occlusal
plane(For posterior region)
Avoid over-bending of film packet
The area of interest is in the center of film.

7. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
2-3mm of film packet should be left beyond the
occlusal plane
The patient holds the packet with finger
Avoid movements of patient,film,or cone during
exposure.
C-Cone,s position:
1-Central ray(C.R)angulation
a-V.A b-H.A
2-Point of entry

8. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
Vertical angulation
Denotes the angle between C.R&occlusal
plane
Vertical angle of maxillary teeth(+ve)
Incisors>>>>>>55-60
Canines>>>>>>45-50
Premolars>>>>35-40
Molars>>>>>>25-30

9. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
V.A for mandibular teeth(-ve)
Incisors>>>>>>15-20
Canines>>>>>>10-15
Premolars>>>>5-10
Molars>>>>>>0-5
Increase V.A 5 in a-shallow palate or floor of
mouth b-flat ridges(edentulous pt)
c-inclined teeth

10. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
Decrease V.A 5 in case
a-high palate
b-deep floor of mouth
Horizontal angulation
It is the angle between CR&mid-sagittal plane
It control width(dimention of tooth)
CR must project through interproximal
surfaces of examined teeth

11. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
H.A Incisor>>>>>zero
Canines>>>>45-60
Premolars>>>60-70
Molars>>>>>>90
Point of entry
The cone is positioned so that CR is directed
to apices of the teeth

12. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
For maxillary teeth>>>points of entry are
located on ALA TRAGUS LINE
Incisors>>>>>tip of the nose
Canines>>>>>0.2cm distal to ala of nose
Premolars>>>vertical line from eye pupil to
ala tragus line
1st
Molar>>>>vertical line from outer canthus
to ala tragus line

13. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
2nd
Molar>>>vertical line from 1cm distal of
outer canthus to ala tragus line
3rd
Molar>>>>vertical line from 2cm distal of
outer canthus to ala tragus line
For mandibular teeth >>>the same as for
maxillary teeth but located on a line
0.5cmabove inferior border of the mandible
Time of exposure depends on area of
rediographed,KV,mA, film speed&age of Pt

14. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
Advantages of bisecting angle technique
1-Easy,quick &comfortable
2-Used in all patients
3-short object-source distance>decrese exp time
4-periapical area can be demonstrated
5-Speed technique
Disadvantages: 1-Not standerdized
2-error of
angulation>>>superimpositionof structures over
the area of interest

15. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
2-The paralleling technique(long cone tech) or
Right angle technique
C.R is perpendicular to both film &tooth
The film is placed in mid of oral cavity to get
parallism between tooth&film>>>image
magnification&unsharpness.
Target-object distance is increased to avoid
unsharpness(16 inches)>>>increase KV,mA,s and
fast film(increase exposure time 4times)
Film holders are used.

16. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
FILM HOLDERS:
1-Rinn instrument 2-Bite block
3-hemostat 4-Cotton rolls
5-Precision rectangular collimating instrument
Advantages of film holders
1-Provide parallism 2-Avoid exposure to Pt fing
Disadvantages
1-Closure of mouth before exposure
2-Cannot examin the periapical structures
3-Limited in small mouths or gagging sesation

21. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
ADVANTAGES OF PARALLELING TECHNIQUE
1-Standerdized>>>used in research
2-Accurate images
3-Avoids superimposition on apices
4-H.A&V.A detrmined by positioning devices
5-No overbending of films

22. PERIAPICAL RADIOGRAPHIC
TECHNIQUES
DISADVANTAGES OF PARALLELING TECHNIQUE
1-Difficult to image all parts of the mouth
2-Increased exposure time
3-Need long cones &film holders
4-Cannot image apical area in shallow palate
5-Discomfort of film holder
6-Time consuming

23. BITE-WING TECHNIQUE
Used mainly for posterior teeth.
The wing is on the tube side of film backet.
Film backet is parallel to long axis of coronal
portion of upper &lower teeth.
CR is perpendicular to center of film

24. BITE-WING TECHNIQUE
TECHNIQUE
MSP is perpendicular to floor&ala tragus line is
parallel to floor
Remove any metallic objects.
Patient should close mouth during exposure.
For premolar teeth >>>the film bite should be
centered over the lower 2nd
premolar &anterior
border of the film extends anteriorly beyond
the lower canine and 1st
premolar.

25. BITE-WING TECHNIQUE
For molar teeth>>>the posterior border of
film is behind the distal surface of most
posteriorly erupted molar &the film bite is
centered over the lower molar teeth.
The patient should close his mouth in centric
occlusion when radiography of posterior teeth
In edentulous patient replace missing teeth by
cotton rolls

26. BITE-WING TECHNIQUE
In anterior bitewing film we should use
1-smaller film size
2-short dimension is parallel to occlusal plane
3-patient closes his mouth in edge to edge
position
4-longer wing to avoid bending of film

27. BITE-WING TECHNIQUE
CONE POSITION
CR IS PERPENDICULAR to film packet.
+ve 5 for premolar &10 for molar(short cone)
+ve 6 for premolar &8 for molar (long cone)
For posterior teeth use 2 films
For anterior teeth use 3 films

30. Occlusal films

34. PANORAMIC RADIOGRAPHY
Produces radiographs for only one section
(slice) of the patient.
Patient is placed so that dental arches are
located in the middle of focal plane.
Patient places edges of incissors in bite block
device.
MSP in midline position.
Patient,s occlusal plane is lowered 20-30
degrees below horizontal plane.

35. PANORAMIC RADIOGRAPHY
Patient,s back is in erect position with
extended neck.
Patient should hold tongue in contact with
hard palate &keep lips closed during exposure
Patient,s breathing is shallow during exposure

36. PANORAMIC RADIOGRAPHY
INDICATIONS
1-Evaluation of truama &3rd
molars.
2-Evaluation of teeth development.
3-Evalution of developmental anomaly.
4-Examination of maxillary sinuses.

37. PANORAMIC RADIOGRAPHY
ADVANTAGES:
1.Imaging broad anatomic region.
2.Relative low radiation dose.
3.Convenient,easy &speedy.
DISADVANTAGES:
1.Fine anatomic details are not demonstrated.
2.Magnification,geometric
distortion&overlapping of teeth.
3.High cost.

38. EXTRA-ORAL TECHNIQUES
1-Lateral views:
a-True lateral b-Lateral oblique
2-PA views:
a-True PA b-Sinus(Water,s
view)
c-Reversed Town,s view
3-AP views:
a-True AP b-Modified Town,s
c-SMV d-Frontal TMJ(transorbital)

41. LATERAL VIEW

44. LATERAL OBLIQUE

47. TRUE PA

50. TRUE PA FOR MANDIBLE

52. AP SKULL FOR TMJ

54. SINUS(WATER,S)VIEW

57. REVERSE TOWN VIEW

60. TOWN VIEW

63. SMV VIEW

66. PANORAMA

70. TMJ

72. END