Panoramic Oral Radiography Flashcards
What are the six possible indications for an OPT? (6)
- Examination of a new dentate patient - Aid to orthodontic treatment - Prior to oral surgery - After to facial trauma - Check for post-op healing - Investigation of TMJ ‘dysfuntion’ (open mouth panoramic)
For what reasons would an OPT be indicated for the examination of a new dentate patient? (2)
- Heavily restored or neglected dentition - Where OPT can indicate teeth that require further more detailed investigation e.g. intra-oral, examination
For what reasons would an OPT be indicated as an aid to Orthodontic Treatment? (2)
- British Orthodontic Society guidelines suggest that routine screening (OPT) is of limited benefit - Radiography is indicated if clinical examination leaves reasonable suspicion as to the presence of any abnormality that may affect the dento-facial development
For what reasons would an OPT be indicated prior to Oral Surgery? (4)
- An OPT is very useful prior to extractions of 3rd molars but sectional films should be considered if they are unilateral extractions - May be useful where multiple extractions are planned - Useful for demonstrating the full extent of large areas of bony pathology - However, prior to apicectomy, root removal, enucleation of small cysts then intra-oral views are more appropriate
For what reasons would an OPT be indicated after Facial Trauma? (2)
- Full OPT excellent for assessing mandibular fractures - However, if clinical examination and history the presence of only dento-alveolar damage then intra-oral views are more useful
For what reasons would an OPT be indicated for assessing Post-Operative Healing? (1)
- Full OPT indicated in some situations e.g possibility of further cyst formation elsewhere in jaws such as in Gorlin’s syndrome
For what reasons would an OPT be indicated for assessing TMJ ‘Dysfunction’? (2)
- Vast majority of patients with TMJ ‘dysfunction’ do not have bony changes which influence management - Most have disc and muscular problems
What is the Radiation Dose and Risk of an OPT? (1)
- Vary due to equipment differences but similar to that received during chest radiography which is approx. equivalent to about 1-5days of additional background radiation
What Preparation of the Patient is required before an OPT? (4)
- Explain the movement of the machine to patient, especially children - Ask patient to remove glasses, neck chain, earrings, dentures - Ask patient to put tongue against the palate during the exposure - Position patient upright – not slumped
How should the Patient be Positioned during an OPT? (3)
- Teeth/jaws must be located within the image layer or ‘facial trough’ - Structures outside this layer ‘facial trough’ will be distorted - Gross distortion can result in non-diagnostic film
What are the six Common Positioning Errors when taking an OPT? (6)
- Patient too far IN - Patient too far OUT - Patient in the CHIN UP position - Patient in the CHIN DOWN position - Patient has head ROTATED - Patient SLUMPED not upright
How does the OPT appear if the Patient is too far IN? (3)
- ANTERIOR incisors are blurred and NARROW - PREMOLARS overlapped - CERVICAL SPINE superimposed on the rami
How does the OPT appear if the Patient is too far OUT? (2)
- ANTERIOR incisors are blurred and WIDER - CONDYLES may fall outside of the sides of the film
How does the OPT appear if the Patient is in the CHIN UP position? (3)
- ROOTS of UPPER INCISORS will be blurred - CONYLES may be lost at the sides of the film - HARD PALATE may be projected over the upper root apices
How does the OPT appear if the Patient is in the CHIN DOWN position? (3)
- ROOTS of the LOWER INCISORS will be blurred - HYOID bone may be projected over the mandible - OCCLUSAL PLANE will form the characteristic ‘SMILE SIGN’
How does the OPT appear if the Patient has their head rotated? (2)
- Teeth on one side of the midline have overlapping contacts and will be MAGNIFIED relative to those on the other side - The WIDTH of the RAMI will be different
How does the OPT appear if the Patient is slumped, not upright? (1)
- Results in an OPAQUE ghost like image of the CERVICAL SPINE to be projected over the midline of the film
Summarise the five situations where the exposure factors should be adjusted and how they should be adjusted (5)
- Black Patient use the next highest kVp/mA - Obese Patient use the next highest kVp/mA - Patient with Large Bone Structure use the next highest kVp/mA - Edentulous Patient use the next lowest kVp/mA - Patient with small bone structure use the next lowest kVp/mA
What are the Four White Lines that can be observes on an OPT? (4)
- Hard Palate - Floor of the Maxillary Sinus - Posterior Wall of Maxillary Sinus - Zygomatic Buttress
What are the Seven Soft Tissue Structures that are usually evident on an OPT? (7)
1) Ear Lobe 2) Soft Palate 3) Nose 4) Nasolabial Fold 5) Lips 6) Dorsum of Tongue 7) Epiglottis
What are the Four Air Spaces that can be seen on an OPT? (4)
1) Between the Tongue and Palate 2) In the Nasopharynx 3) In the Oropharynx 4) Outlining the Epiglottis
What are Ghost Images on an OPT? (3)
- Formed when the object is located between the x-ray source and the centre of rotation - Appears on opposite side from real image - Always higher up and blurred
What are the thirty panoramic bony anatomy landmarks? (30)
1) External Auditory Meatus
2) Articular Eminence
3) Sigmoid Notch
4) Zygomatic Arch
5) Zygomatic Buttress
6) Lateral Pterygoid Plate
7) Pterygo-Maxillary Fissure
8) Posterior Wall of Maxillary Sinus
9) Floor of Maxillary Sinus
10) Hard Palate/Floor of Nose
11) Infra-Orbital Rim
12) Infra-Orbital Canal
13) Nasal Cavity
14) Inferior Nasal Concha
15) Nasal Septum
16) Anterior Nasal Spine
17) Alveolar Bone Margin
18) Styloid Process
19) Calcified Stylohyoid Ligament
20) Cervical Spine/Vertebra
21) Foramen Transversarium
22) Condyle
23) Coronoid Process
24) External Oblique Ridge
25) Mandibular Foramen
26) Inferior Dental Canal
27) Mental Foramen
28) Hyoid Bone
29) Bony Cortex of Inferior border of Mandible (Mandibular Cortex)
30) Antegonial Notch
How should Film Viewing be approached when Interpreting Panoramic Radiographs? (5)
- Always use appropriate viewing box
- Make sure you know which side is which
- Adopt a systematic viewing technique
- Look at the whole film not just your area of interest; avoid tunnel vision
- Write a report of your findings
What was wrong when this radiograph was taken? (1)
Patient was too far in
What was wrong when this radiograph was taken? (1)
Patient is too far out
What was wrong when this radiograph was taken? (1)
Patient was in the ‘chin up’ position
What was wrong when this radiograph was taken? (1)
Patient was in the ‘chin down’ position
What was wrong when this radiograph was taken? (1)
Patient’s head was rotated
What was wrong when this radiograph was taken? (1)
PAtient was slumped, not upright
How should Film Viewing be approached when Interpreting Panoramic Radiographs?
- Always use appropriate viewing box
- Make sure you know which side is which
- Adopt a systematic viewing technique
- Look at the whole film not just your area of interest; avoid tunnel vision
- Write a report of your findings
