Download Intraoral Radiographs

Intraoral Radiographs
Introduction
• In order to see what is the state of a
patient’s oral cavity, then dental
radiographs are performed.
• Why Radiology?
• To see pathology hiding below the gingiva or
inside the tooth
• Evaluate an area where the teeth appear to be
missing
• To document the obvious - supporting treatment
decisions
• For client communication
• Medical/legal documentation
• Postoperative confirmation of proper extraction
• Preoperative, intraoperative, and postoperative
endodontics
• Follow progression of pulpal pathology and/or
periodontal disease
• For prepurchase exams on show dogs to see if
the proper number of teeth exist
Documentation
• Periodontal disease is the most common
ailment in small animals.
• The x-ray shows lesions above and below
the gum line.
• Legal uses of radiographs to support
treatment decisions prove invaluable.
• The dental radiograph becomes part of
your patient’s permanent medical record.
Examining serial radiographs of
periodontal or endodontic cases taken at
three to six-month intervals provides
invaluable information concerning
progression or resolution of disease.
X-rays help us determine
whether extractions are
necessary.
When to take a Radiograph
• When a tooth is mobile
• When gingiva bleeds with or without
probing When a tooth is fractured (either
enamel, dentin, or pulpal exposure)
• When a tooth is discolored (pulpitis)
• When furcation exposure is present
(periodontal disease)
• When teeth are missing without
explanation
• When a feline ondoclastic resorptive lesion
(FORL) is noted.
• Prior to extraction for anatomical
orientation and documentation
Anatomy of Intraoral
Radiograph Machine
• Position Indicating Device (PID) - is an extension
placed on the tube head at the collimator
attachment. To minimize the amount of radiation
exposure, the PID is lead lined. The shape of the
PID may be circular or rectangular..
• Arm - the connection between the x-ray tube and
control pannel.
• Control Panel - contains timer, kilovoltage, and / or
milliamperage regulators.
• Electric timer-as a safety device, the timer
operates only while the switch is being depressed
and automatically cuts off electric current at the end
of the exposure. The timer resets itself after each
exposure.
Tooth Film Distance
• When utilizing intraoral technique, film is
placed parallel to the palatal or lingual
tooth surface.
• Due to small animal oral anatomy this is
not always possible. Instead, a bisecting
angle technique is used resulting in a 2050 degree angulation of the x-ray beam to
the film plane, depending on which tooth is
radiographed
Rules for Successful Positioning
• The closer the object being radiographed is
to the film, the sharper and more accurate
the image.
• Use the longest film focal distance practical
• Direct the central ray as close to a right
angle (or bisecting angle) to the film as
possible
• Maintain as parallel interface between the
film and object as possible
Proper positioning for a radiograph of
the mandibular premolars and molars.
Positioning for a study of the
mandibular incisors and canines.
Positioning for the rostral mandibular
premolars. This can also be used to obtain a
lateral view of the incisors and canine tooth.
Notice that the incisor teeth are
missing!
Positioning for the maxillary incisors.
Maxillary incisors!
Positioning for a study of the maxillary
premolars. This can also be used to obtain a
lateral view of the maxillary incisors and
canine tooth.
And here’s the result!
Digital imaging dental radiology
• Digital imaging is a recent technical
advancement in dental radiology. It
will be as popular or even replace,
film-based imaging in the future.
• Computer image capturing and
image enhancement has many
advantages compared to the
traditional film systems. With digital
imaging, the dental radiograph
machine is still used to expose the
lesion, but instead of film, a sensor
pad is placed inside the mouth,
accepts the image, and transfers it
to the computer screen.
Film
• Small intraoral film is used in dental radiography.
It is inexpensive, flexible, and provides great
detail. Non-screen film is preferable due to the
high definition necessary to interpret dental
lesions. Dental film is conveniently used for intra
or extra-oral placement.
• Individual dental films are packaged in a light
tight packet that is made of either plastic or
paper. Inside the packet, film is positioned
between an inner lining of two sheets of black
paper. A sheet of lead foil is located at the "back"
of the packet, next to the tab opening. Lead foil
protects the film from secondary radiation, which
may cause the film to fog
Film Continued
• The back of the packet has a tab opening
used to remove film for processing. This side
is placed next to the tongue or palate.
• Intraoral dental film is packaged singly or with
two films per packet. When two films are
exposed, the practitioner may use the second
film to give to the client or referring
veterinarian. Film packets are color-coded—
green indicates a single film packet, gray a
two-film packet.
Components of intraoral
dental film.
Lead
foil
Waterresistant
wrapper
Dental
film
Black
paper
Film Speed
• Commonly used dental film is available as
speed D (ultra speed) and speed E (ekta
speed). Speed E film is rated at twice the
speed of D film, requiring half the
exposure, with small loss of quality.
• Ultra speed is used predominantly in
veterinary dentistry.
Film Sizes
• Three sizes of dental film are frequently
used in veterinary dentistry:
• child periapical size 0 measures 7/8 x 1 5/8
inches-used mostly in cats, exotics, and small
dogs
• Adult periapical size 2, also called standard size
measures 1 ¼ x 1-9/16 inches. Size 2 is the
most popular size used.
• Occlusal size 4 measures 2 ¼ x 3 inches.
Occlusal film used to radiograph larger teeth
and survey studies
Film Dot
• Dental film is embossed with a raised
dot in one of the corners. The convex
side of the dot indicates front side of the
film. The dot is used to identify right from
left. The convex (raised) dot is placed at
the occlusal edge and toward the x-ray
tube. The concave (depressed) dot is
placed toward the tongue or palate.
• To determine whether a film is on the
right or left side, imagine where the
convex dot is located, and identify the
progression of teeth from incisors to
molars.
Radiographic Landmarks
• It is important to be able to look at a film
and identify the area exposed.
• Maxillary incisors will show a large radiodense
(white area) distal to the teeth, with two ovals
representing the nasal area. All incisor teeth
have one root
• Mandibular incisors - look for a black space
separating mandibular rami
• Maxillary premolars and molars - look for a
fine while line representing the maxillary recess
apical to the roots
• Mandibular premolars and molars - look for
radiolucent (black areas) above and below the
jaw. Other than the first premolar (in the dog)
and third premolar (in the cat), all mandibular
premolars and molars have two roots
It is important to know how many roots
each tooth has. Can you think of any
reasons why?
Positioning of Film and Patient
• Place film inside the mouth, parallel to the
teeth to be examined.
• Bisecting angle technique is used in
most exposures. Lay film far enough inside
the animal’s mouth so that its root
structure will be projected on the film.
Imaginary lines are drawn along the long
axis of the tooth and the plane of the film.
The point where these two lines meet will
create an angle. Instead of aiming the
central beam perpendicular to the film as
in the parallel technique, the central beam
is aimed perpendicular to the line bisecting
the angle created between the line of the
tooth and line of the film
Bisecting Angle Technique: this minimizes
image distortion and produces an accurate
image of the canine teeth on the dental film.
In any 90 degree arc, there is one angle that will
allow an x-ray beam to cast an accurate shadow
of the tooth on the film.
1. Bisecting Angle: Find the middle of the “long axis of tooth and film.
2. You now want to use the BA and x-ray head to create a 90 degree
angle, no larger, no smaller.
This takes practice, patience and time.
Tubehead on xray machine
Film
Distance
between the
tooth and
the film.
CTVT
CTVT
pg.pg.
888888
This angle will make the
tooth appear short on the xray film.
Tube head
This angle makes the tooth
appear longer on the x-ray.
Tubehead
On
X-ray
machine
FILM
Film Processing
• Film may be developed:
• By hand with regular or rapid dental processing
solutions in the darkroom
• With Chairside developer - a portable light safe box
with developer, fixer, and water in small containers.
Putting your hands through two diaphragms in a
lighted room accesses the solutions. The box’s top,
an orange or red Plexiglas safety filter, enables you
to see inside. The whole process from opening the
film packet to examination of a rinsed film takes
approximately one minute
• Automatically Film is placed into one end of the
automatic dental processor and comes out fully
developed, fixed, and dried in 2 to 7 minutes. Using
standard veterinary automatic processors are
discouraged because small dental films may become
lost in the processor, and tape used to attach to
larger films, may harm the processor’s rollers
• Instant dental x-ray film (Veterinary dental film
system VDFS-Hawaii Mega-cor, Inc. Aiea, Hawaii)
develops in 30 seconds within the film packet after
infusion of developer and fix solutions
Steps for manually processing
dental x-rays
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Once the film packet is in a light secured area, open the
packet tab on the packet and slide forward the paper
liner and film. This will present film to be processed.
Only touch the sides of the film with your fingers
A film hanger is attached to the film. Film should extend
horizontally from the clip. Give the film a gentle tug to
make certain it is firmly attached to the clip
Place the film into the developing solution for 10-30
seconds (depending on room temperature - longer time if
less than 68 degrees)
The film is rinsed in distilled water for 10 seconds Place
the film in the fixing solution for 30 seconds
Rinse for 30 seconds in distilled water After viewing, the
film is placed in the fixer for 5 minutes and a distilled
water rinse for 20 minutes
When rinsing is complete, hang the radiograph on a rack
to dry or use a hair drier for rapid drying
Chemicals should be changed at least once weekly.