Combined Set for Panoramic

theory and principles; positioning lights; technique

What are the 4 parts of the Planmeca Promax cephalometric and panoramic machine?

- lateral ceph sensor

- soft tissue filter

- radiation source for pan and lateral ceph

- panoramic sensor

What are general concepts of panoramic radiography?

- produces single image of large anatomic area

- structures are flattened and spread out

What are advantages of panoramic radiography?

- broad coverage of facial bones and teeth

- convenience for the patient

- used on compromised patients

- efficient in producing an image

- low radiation dose to patient

A panoramic is equivalent to ___ bitewings

A) 1

B) 2

C) 3

D) 4

E) 5

F) 6

D) 4

What are disadvantages of panoramic radiography?

- doesn't show fine detail

- proximal surfaces of premolars overlap

- uneven magnification

- geometric distortion

- operator sensitive

- anatomy can hide area of interest

- area of interest may be outside the focal trough

What are common clinical applications for panoramic radiography?

- overall evaluation of the dentition

- dentomaxillofacial trauma

- evaluation of impacted teeth

- extensive disease

- examine intraosseous pathology

- tooth development

- edentulous patient evaluation

- implant site assessment

- gross assessment of TMJ

What are image receptors for panoramic radiography?

- CCD direct exposure

- indirect exposure

What part of the cassette interacts with radiation?

phosphors

Why doesn't the pan provide fine details?

radiation comes through the film back to the panel and comes back out again --> spreads the image out/bounces around

How is the panoramic image created?

sequential image formation

What is the size of the focal trough affected by?

- arch path

- velocity of film and tubehead

- collimator width

True/False: the position of the object in the trough determines the size and shape of the resultant image

True

For a panoramic image, the most posterior part of structure ends up more ___

A) superior

B) inferior

A) superior

For a panoramic image, the most anterior part of structure ends up more ___

A) superior

B) inferior

B) inferior

How are real images formed?

objects that lie between the center of rotation and the receptor

How are double real images formed?

objects that lie posterior to the center of rotation and are intercepted twice by the x-ray beam

What are structures that are double real images?

- body of hyoid bone

- epiglottis

- palatal torus

- hard and soft palate

- cervical spine

How are ghost images formed?

objects located between the x-ray source and the center of rotation

What structures are ghost images?

- earrings

- cervical spine

- hard palate

- hearing aids

Ghost images are on the ___ side of the real counterpart

A) same

B) opposite

B) opposite

Ghost images appear ___ than the real counterpart

A) lower

B) higher

B) higher

True/False: the ghost image is more blurred than the real counterpart

True

The ___ component of a ghost image is more blurred than the ___

A) horizontal, vertical

B) vertical, horizontal

B) vertical, horizontal

True/False: ghost images appear in the same orientation as the real counterpart

True

What are the 3 positioning lights?

- mid-sagittal

- Frankfort plane

- focal trough

What is the correct order of the positioning lights?

I. Frankfort plane

II. focal trough

III. mid-sagittal

A) I, II, III

B) III, II, I

C) I, III, II

D) III, I, II

D) III, I, II

What are ways to achieve the correct positioning?

- instruct patient to move their head

- physically move the patient

How is the mid-sagittal light positioned?

down the middle of the forehead, nose, lips, and chin

What does the mid-sagittal light contribute to?

symmetry

What is the result if the head is rotated regarding the mid-sagittal light?

symmetry is lost

What are the two bony landmarks for the Frankfort horizontal plane?

- inferior orbital margin

- external auditory meatus

What is the clinical landmark for the Frankfort horizontal plane?

tragus

What does the Frankfort horizontal plane contribute to in the image?

- smile

- both condyles

- entire mandible

What would occur if the chin is up regarding the Frankfort horizontal plane?

- occlusal plane of image is frowning

- condyles fall off sides of the image

If the chin is ___, the image is frowning

A) down

B) up

B) up

What is the result of the chin is down regarding the Frankfort horizontal plane?

- occlusal plane is image is smiley

- condyles are often over the top edge of the film

- spine encroaches into the middle of the image

If the chin is ___, the image is too smiley

A) up

B) down

B) down

True/False: if the chin is down, the image is frowning

False

What contact is the focal trough placed through?

mesial of #11

What does the focal trough light contribute to?

puts teeth in good presentation where you can see from apex to crown

What is wrong with the patient if the anteriors are too wide?

A) patient is too close to film/receptor

B) patient is too far away from film/receptor

B) patient is too far away from film/receptor

What is wrong with the patient if the anteriors are too narrow?

A) patient is too close to film/receptor

B) patient is too far away from film/receptor

A) patient is too close to film/receptor

What should the patient remove for the panoramic?

- intra-oral appliances

- glasses

- earrings

- piercings

- necklaces

- hearing aids

- hair accessories

- coats, jackets, hoodies, bulky clothing

True/False: an apron is required when taking a panoramic

False

If a patient wishes to wear a protective apron when taking a panoramic, which one would be appropriate?

A) apron without thyroid collar

B) apron with thyroid collar

A) apron without thyroid collar

Why should an apron with a thyroid collar not be worn when taking a panoramic?

collar blocks x-ray beam

What is the perfect posture for taking a panoramic?

- standing straight

- feet flat on the floor

- shoulders even

What could happen if the patient is kyphotic?

ghost shadow of spine is exaggerated

Why should the patient swallow and keep their tongue at the roof of their mouth when taking the panoramic?

fills airspace

What are common errors of patients for panoramic?

- maxillary and mandibular incisal edges not in groove of bitestick

- lips not closed around bitestick

- patient doesn't press entire tongue against roof of mouth

What appears on the image if the patient doesn't keep their tongue at the roof of their mouth?

black rainbow

What button do you click to activate the panoramic unit?

P

How many icons are there in the panoramic unit?

5

What icon on the panoramic unit is for an average human?

4th

What position is the pan unit in for go entry 1?

unit is furthest away from platform

What position is the pan unit in for go entry 2?

unit is in the intermediate position

What position is it appropriate for the patient to enter the pan unit?

A) go entry 1

B) go entry 2

B) go entry 2

True/False: you should use cotton rolls for the patient if they are fully edentulous

False

When do you use cotton rolls to open the posterior dentition?

missing any of the 4 centrals

What class would you use a chin cup when taking a pan?

class II

What should patients remove for a pan/lateral ceph?

- intra-oral appliances

- glasses

- earrings

- piercings

- necklaces

- metal hair accessories

- hearing aids

- coats, jackets, sweatshirts, bulky clothing, anything with a hood

What is the proper apron placement?

- low on the neck

- flat around neck and shoulders

What are the lights for the pan unit?

- mid-sagittal

- Frankfort plane

- focal trough

What are ways to achieve correct positioning of the patient?

- verbally instruct the patient to move their head

- physically move the patient into the path of the light

Where is the mid-sagittal light on the pan unit positioned?

down the middle of the forehead, nose, lips, and chin.

What are the two bony landmarks for the Frankfort horizontal plane?

- infraorbital margin

- external auditory meatus

What is the clinical landmark for the Frankfort horizontal plane?

mid-tragus

Frankfort horizontal plane should be parallel to what?

to the floor

What tooth and contact is the focal trough light placed?

mesial #11

Where is the focal trough line positioned for edentulous patients?

corner of the mouth

How long do you have to press the button for pan and lateral ceph?

press and hold the button during the entire exposure

What is returned to the radiology assistant after the pan?

- bitestick

- chin cup

What do you have to press to activate the lateral ceph machine?

C

How many icons are there for lateral ceph?

5

What icon for lateral ceph is used for hand/wrist?

1

What icon is used for a teenager for lateral ceph?

3