The document discusses the history and development of dental radiography techniques, provides guidelines for selecting appropriate radiographs for pediatric patients based on their age and dental development, and describes commonly used intraoral and extraoral radiographic techniques including advantages and indications for each. It also covers topics like digital radiography, cone beam computed tomography, and radiation safety protocols.
Historical Background and Techniques of Dental Radiography
1.
2. Historical background:
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1895 Roentgen discovers x-rays
1896 First intraoral radiograph taken
1913 first x-ray tube invented
1904
Bisecting technique developed
3. 1925 Introduction of bite wing technique
1959 Panoramic technique developed
1920 Paralleling technique developed
1923 develops dental x-ray machine
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4. General indications :
Early diagnosis of caries prevents the pediatric patient from experiencing
dental pain, extraction, and emotional stress.
eruptive or developmental problems can be discovered with the use of
radiographic images, and early treatment of these problems may reduce the
need for prolonged orthodontic procedures.
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5. Note
if the child has an
exaggerated gag reflex
to the placement of the
film. The use of topical
anesthetic agents may
be beneficial
The selection of appropriate radiographs for the
pediatric patient depends on :
1. the age of the child
2. the size of the oral cavity .
3. the level of patient cooperation.
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6. RADIATION SAFETY AND
PROTECTION
There are critical organs vulnerable to possible development
of late effects. and may be associated with adverse biologic
effects as :
1. the cancer of skin , breasts , thyroid and salivary glands
2. red bone marrow (leukemia) .
3. the gonads (mutation, infertility, and fetal malformations) .
4. the eyes (cataracts) .
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NOTE :
protecting the patient by using a lead apron and thyroid
collar.This method does not provide complete protection but it
does provide a great reduction in exposure.
7. Reduction in radiation to the patient by:
1. Faster film speeds.
2. Panoramic radiography have reduced exposure .
3. Use of a long rectangular collimator reduces the area
unnecessarily exposed to radiation by almost 4 square
inches compared with a round collimator.
4. digital radiography.
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8. Dental Film
• Dental film is available in six speeds, A, B, C,
D, E and F.
• Only D, E and F are used in practice with E
being the preferred speed.
• There are also six sizes of film available, with
size 4 (57mm x 76mm) and size 2 (31mm x
41mm) and size 0 being most useful.
9. SELECTION CRITERIAAND RADIOGRAPHIC
EXAMINATIONS
Primary Dentition :
proximal surfaces of the teeth cannot be visually and tactilely inspected + child is cooperate
dental radiographs to determine the presence of interproximal caries.
child is uncooperative radiograph deferred until behavior improves.
open contact surfaces of all teeth can be examined radiographs are not indicated.
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10. SELECTION CRITERIAAND RADIOGRAPHIC
EXAMINATIONS
Early Transitional Dentition (After Appearance of Permanent First Molars or
Permanent Mandibular Incisors, or Both)
Radiographs are obtained to evaluate the presence of interproximal caries, developmental
anomalies of teeth, and pathologic conditions of the hard and soft tissues of the mouth, jaws,
and associated structures.
Early Permanent Dentition (After Puberty; After Patients Have Achieved Most
of Their Adult Stature; Late Adolescence)
Radiographs are obtained to evaluate the same tissues as in the early mixed dentition and to
check the position and developmental status of the third molars.
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11. RADIOGRAPHIC EXAMINATIONS
When a new patient is seen at the dental office and no previous radiographs are
available, it may be necessary to obtain a baseline series of radiographs.
These examinations include the following.
Four-Film Series
Eight-Film Survey
Twelve-Film Survey
Sixteen-Film Survey
- •.
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13. Eight-Film Survey
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• A max and mand anterior occlusal
(or periapicals).
• a right and left max molar
periapicals.
• a right and left mand molar
periapical.
• 2 posterior bite-wings.
17. COMMONLY USED
RADIOGRAPHIC TECHNIQUES
1) Bite-wing ( intra oral )
2) Periapical ( intra oral )
3) Occlusal ( intra oral )
4) Panoramic( extra oral )
5) Cephalometric Radiographs ( extra oral )
EX : Lateral Cephalometric
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18. 1) Bite-wing Technique
A No. 0 bite-wing film is usually the most suitable size for the
smaller patient .
some children’s mouths are large enough to receive. a No. 2
bite-wing film.
The dentist holds the bite-tab against the occlusal surfaces of the
patient’s mandibular teeth with an index finger, and the patient
is instructed to “close slowly.” 11/12/2022 18
20. 1) Bite-wing Technique
indications :
for detection of interproximal caries, occlusal caries that have
penetrated into the dentin, and possible caries under existing
restorations.
For evaluation of crestal bone level.
Evaluation of restoration contours.
Use to visualize erupting permanent teeth.
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22. 2) Periapical Technique
There are essentially two methods
of taking periapical radiographs (
paralleling and bisecting angle
techniques). Each has benefits
and limitations when used with
the pediatric patient.
identification dot is placed
toward the occlusal surface.
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23. 2) Periapical Technique
to detect :
1. Change in the integrity of the teeth. (Dilaceration, root
resorption, ankylosis, foreign bodies and displacement).
2. Alternation in teeth calcification (pulp stones, amelogensis or
dentinogensis imperfecta).
3. Fractured crowns, roots or bone.
4. Thickened periodontal membrane or presence of periodontal
pockets.
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24. 2) Periapical Technique
to detect :
5. External and Internal root or bone resorbtion .
6. Anomalies of the supporting bone and associated structures
(cysts, supernumerary or ectopically erupting teeth, etc.)
7. In pulp therapy: - Shows number of root canals, length,
morphology + Evaluate the root canal filling material after
treatment.
8. Periapical films of the canine areas could be obtained if
these teeth were not clinically palpable by 9 years of age
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25. a) Paralleling Technique
the object ( long axis of the tooth) and the (film)
to be parallel in all dimensions.
The film packet is placed farther away from the
object, particularly the maxilla.
Because the film is placed farther away from the
object, a film holder is necessary .
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26. b) Bisecting Angle Technique
The clinical application of this rule has the central ray directed
perpendicularly to a plane that bisects the angle created by the
long axis of the tooth and the fi lm.
This technique is not as accurate as the paralleling technique and
should be used as an accessory technique when paralleling
technique is uncomfortable.
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28. 3) Occlusal Technique
a) Anterior Maxillary Occlusal Technique:
1. the patient’s occlusal plane should be parallel to the floor .
2. A No. 2 periapical film is placed in the patient’s mouth.
3. The anterior edge of the film should extend approximately 2 mm in front of
the incisal edge of the central incisors.
4. The central ray is directed to the apices of the central incisors and a
centimeter (half-inch) above the tip of the nose and through the midline.
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30. 3) Occlusal Technique ….cont…>>>
b) Posterior Maxillary Occlusal Technique
1) the patient’s occlusal plane should be parallel to the floor.
2) A No. 2 periapical film is placed in the patient’s mouth so that the long
axis of the film is parallel to the floor .
3) The outer buccal edge of the film should extend approximately 2 mm
beyond the primary molar crowns.
4) The central ray is directed toward the apices of the primary molars as
well as interproximally.
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32. 3) Occlusal Technique ….cont…>>>
c) Anterior Mandibular Occlusal Technique
1) The film placement is identical to that for the anterior maxillary occlusal
technique, except that the anterior edge of the film is 2 mm beyond the incisal
edge of the lower incisors.
2) The patient’s head is positioned so that the occlusal plane is at a –45-degree
angle.
3) the central ray is directed through the symphysis
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34. 3) Occlusal Technique ….cont…>>>
Used for evaluation of :
1) trauma to the anterior teeth .
2) Presence and position of impacted and
supernumerary teeth.
3) Determine the BL extension of pathological
lesions.
4) Provides information about extent and
displacement of fractures in the maxilla or
mandible.
5) Stones in submaxillary and sublingual
salivary glands.
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35. 4) Panoramic Radiography
the x-ray film and the source of the x-rays
move simultaneously in opposite directions
at the same speed.
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37. USES of Panoramic Radiography :
1) A complete survey can be made of the teeth and related structures.
2) Supernumerary teeth , congenitally missing teeth , tumors and
cysts can be examined and evaluated.
3) The location and position of impacted teeth may be determined.
4) Fractures of the lower face may be located.
5) Growth patterns of the jaws can be studied and evaluated.
6) Stage of dentition and dental age.
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38. Advantages of Panoramic Radiography
1. Large anatomical area covered.
2. Relatively low dose.
3. Easy to operate.
4. can be used for examination of children and handicapped
Because the examination is obtained without placement of
in the mouth.
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40. 5 )Lateral Cephalometric
Uses of lateral cephalometric x-rays :
1. To evaluate the relationship between the
maxillary and mandibular basal bones.
2. To assess the dental relationships.
3. To study the facial soft-tissue contours .
4. Identify trauma.
41. Localization Techniques
Tube-Shift Localization (Clark)
SLOB Rule
Same Lingual Opposite Buccal
One method of localizing embedded or unerupted teeth uses the
buccal object rule, which states that the image of any buccally
oriented object appears to move in the opposite direction from a
moving x-ray source. On the other hand, the image of any
lingually oriented object appears to move in the same direction
as a moving x-ray source .
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43. [ Cone Beam Computed Tomography (CBCT)]
added 3-dimensional capabilities that have many applications
in dentistry.
When using CBCT, the resulting imaging is required to be
supplemented with a written report that includes full
interpretation of the findings.
The main contraindication is disabling conditions that might
cause a patient to be uncooperative.
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44. Digital Radiography
Digital radiography (digital x-ray) is
the latest technology used to take
dental x-rays.
This technique uses an electronic
sensor to capture and store the digital
image on a computer.
45. Digital Radiography
This image can be viewed and enlarged helping the dentist
detect problems easier.
Digital x-rays reduce radiation 80-90% compared to
traditional dental x-rays.
Disadvantages:
Rigid and thick sensor.
Expensive .
Most have wire connecting sensor to computer.
Editor's Notes
The bisecting angle technique is based on a principle called the rule of isometry, which basically states that two triangles are equal if they have two equal angles and a common side.
The SLOB rule is used to identify the buccal or lingual location of objects (impacted teeth, root canals, etc.) in relation to a reference object (usually a tooth). If the image of an object moves mesially when the tubehead is moved mesially (same direction), the object is located on the lingual
If the image of the object moves distally when the tubehead moves mesially (opposite direction), the object is located on the buccal.
.