Term
Describe the basic principle of the paralleling technique? |
|
Definition
The film and the long axis of the tooth are parallel and the central ray is perpindicular. |
|
|
Term
what happpens to the image when the distance between the film and the object increases? |
|
Definition
The image becomes magnified and loss of difinition occurs |
|
|
Term
Because of the anatomical configuration of the oral cavity image magnification can occur due to increased object film distance. How could this be prevented? |
|
Definition
Increase the distance between the target and the x-ray source. "longcone technique" |
|
|
Term
How does the "longcone technique" help decrease image magnification? |
|
Definition
It ensures only the most parallel rays will be directed at the tooth and film |
|
|
Term
Name the film holders that can be used for the paralleling technique? |
|
Definition
Rinn XCP intruments, Precision film holders, Stabe film holders, EEZEE-grip film holders, Hemostat film holders |
|
|
Term
[image] Name this x-ray holder |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
[image] Name this type of holder |
|
Definition
|
|
Term
Why is a film holder necessary with the paralleling technique? |
|
Definition
It helps position the film parallel to the long axis of the tooth and eliminates the need for the patient to stabilize the film. |
|
|
Term
What size film do you use when taking an anterior x-ray using a paralleling technique? |
|
Definition
Size 1 placed in a verticle position high in the palate |
|
|
Term
what size film do you use when taking a posterior paralleling x-ray? |
|
Definition
size 2 placed in a horizontal direction |
|
|
Term
What are the five basic steps for the correct paralleling technique? |
|
Definition
1. Film Placement 2. Film position (parallel to the long axis) 3.Vertical Angulation(central line must be perpendicular to the long axis) 4. Horizontal Angulation(central line line must go directly between the contact) 5. Film exposure (prevent cone cuts) |
|
|
Term
what tooth anatomy should you should see on a posterior molar periapical? |
|
Definition
1. The apices of the 1st, 2nd, and 3rd molars or just the molars that are present 2. Distal of the second premolar 3. Alveolor crest 4. contact areas and crowns |
|
|
Term
What tooth anatomy should you be able to see in a premolar PA? |
|
Definition
1. Apices of the premolars 2.alveolar crest and crowns 3. distal of the canine |
|
|
Term
Describe the patient preparation and equipment preparations that should be used in the paralleling technique. |
|
Definition
1. Briefly discribe the x-rays procedure to pt 2. Adj. chair so that the pt's max. arch is parallel to the floor and their midsagittal plane is perpendicular to the floor 3. Place the lead apron and thyroid collar on the patient 4.Remove all partials, dentures, gum, retainers, glasses object from the pt's mouth and face 5.Set kVp, mA, and set up all x-ray holders |
|
|
Term
What modifications would you make when taking mand. molar PA's on a pt with a shallow palate? |
|
Definition
You want to achieve a less than 20 degree angle between the tooth and the film. This can be complished by using cotton rolls on each side of the bite block |
|
|
Term
What are some advatages of the paralleling technique? |
|
Definition
1. Accuracy 2. Simplicity 3. Duplication |
|
|
Term
What are some disadvatages of paralleling? |
|
Definition
1.Film placement 2. Discomfort |
|
|
Term
What happens to the radiographic image when the oject-film distance is increases? |
|
Definition
The image can be magnified There can be a loss of definition |
|
|
Term
What piece of equipment is required to hold the film parallel to the long axis of the tooth in the paralleling technique? |
|
Definition
|
|
Term
What do the letters X , C , P stand for? |
|
Definition
X = extension C = cone (PID) P = parallelling |
|
|
Term
What size film do you use for an anterior XCP holder and a posterior XCP holder? |
|
Definition
Anterior = size 1 Posterior = size 2 |
|
|
Term
Why is an increased target-film distance required in the paralleling technique? |
|
Definition
To avoid image magnification |
|
|
Term
What should the relationship be between the central ray and the film? |
|
Definition
|
|
Term
Describe the relationship between the film and the long axis of the tooth in the paralleling technique? |
|
Definition
the film and the long axis are parallel |
|
|
Term
What direct are the anterior and posterior films placed? Horizontal or vertical |
|
Definition
Anterior = Vertical Posterior = Horizontal |
|
|