DENT 1050 Test Study; ch. 30, 31, 32, 33, 35 & lab ch. 18

Question 1

Bisecting Technique

Answer 1

Film Placement: Selected teeth;
Film Position: film is placed against the tooth, the occlusal end of the film should extend at least 1/8 inch beyond the incisal/occlusal surface;
Vertical angulation: central ray is directed perpendicular to the imaginary bisector that divides the angle formed by the film and long axis of the tooth;
Horizontal angulation: Through the contacts

Question 2

Target to tooth

Answer 2

central ray is directed perpendicular to the imaginary bisector that divides the angle formed by the film and long axis of the tooth;

Question 3

Elongation

Answer 3

Results from insufficient vertical angulation

Question 4

Tools

Answer 4

stabe blocks or snap a rays

Question 5

Bite blocks

Answer 5

Stabe Bite-block: (used in both the paralleling and bisecting techniques)
The scored front section is removed and the film is placed as close to the teeth as possible

Question 6

Snap a ray

Answer 6

used in both paralleling and bisecting techniques

Question 7

Caries definitions

Answer 7

Incipient Interproximal Caries (Class I): extends less than ½- way through the enamel
Moderate Interproximal Caries (Class II): extends more than ½-way through the enamel but does not yet involve the DEJ (or dentin)
Advanced Interproximal Caries (Class III): extends to or through the DEJ and into dentin (but not more than ½-way through the dentin)
Severe Interproximal Caries (Class IV): extends more than half the distance to the pulp (through the dentin)
May appear clinically as a hole (cavitation) in the tooth

Question 8

Cysts - radiopaque or radiolucent

Answer 8

1. Focal opacity- well defined
   a. Condensing osteitis
   
   2. Target lesion- localized opaque, surrounded by radiolucent halo.
      a. Benign cementoblastoma
   3. Multifocal confluent- multiple radiopacities that appear to overlap or flow together.
      a. Osteitis deformans and florid osseous dysplasia
   4. Irregular- poorly defined pattern, usually malignant
      a. Osteosarcoma and chondrosarcoma
   5. Ground glass- granular or pebbled looking bone
      a. Fibrous dysplasia, osteitis deformans
   6. Mixed lucent-opaque- has mixed radiolucent and radiopaque look.
      a. Calcifying tumors – compound odontoma

Question 9

Dental materials look like what on radiographs?

Answer 9

Metallic restorations (amalgam, gold)
	1. Opaque or white area on film

Nonmetallic Resotration
(porcelain, composite, acrylic)
1. Appear radiolucent to slightly opaque

Question 10

Isometry

Answer 10

equality of measurement; mirror image; Rule of Isometry: two triangles are equal if they have two equal angles and share a common side

Question 11

Foreshortened

Answer 11

Results from excessive vertical angulation (too steep);

Can result if the central ray is directed perpendicular to the plane of the film rather than the imaginary bisector

Question 12

Diatorics

Answer 12

used in anterior porcelain denture teeth

Question 13

Post and Core

Answer 13

endodontic therapy and tooth build-up; are radiopaque

Question 14

Porcelain crowns

Answer 14

have a thin line of cement around the tooth prep

Question 15

Gold crowns and bridges

Answer 15

large and smooth; well adapted margins.

Question 16

Unilocular:

Answer 16

small and non-expansile and have borders that may be corticated or non-corticated ( dense or not dense border)

Question 17

Multilocular

Answer 17

multiple radiolucent compartments and is a larger lesion

a. Well defined coricated margins

	b. Frequently expansile-displacement of 			buccal and linqual plates of bone.

Question 18

Moth-eaten pattern

Answer 18

ill-defined borders

Question 19

Radiopaque

Answer 19

Metallic restorations, Bone, Enamel, Newer composite restorations, Dentin

Question 20

Radiolucent

Answer 20

a. Caries
b. Air spaces
c. Soft tissue
d. Abscesses
e. Dental pulp
f. Periodontal ligament space

Question 21

Final interpretation

Answer 21

made by dentist

Question 22

Interpretation terminology

Answer 22

Interpret:  
	To offer an explanation
Interpretation: 
	An explanation
Image interpretation: 
	An explanation of what is viewed on a 	dental image; the ability to read what 	is revealed by a dental image.
Diagnosis:  
	The identification of a disease by 	exam or analysis.

Question 23

interpretation and dental team

Answer 23

Other members of dental team are restricted by law to diagnose.

Question 24

interpretation of caries

Answer 24

A lower kVp yielding a high contrast and short-scale is best

Question 25

Caries classes: interproximal

Answer 25

Class I: Incipient interproximal
Class II: Moderate interproximal
Class III: Advanced interproximal
Class IV: Severe interproximal

Question 26

Caries classes: occlusal

Answer 26

Incipient Occlusal Caries
Moderate Occlusal Caries
Severe Occlusal Caries

Question 27

Root Fractures:

Answer 27

occur most often in max. central area;
It is critical that the paralleling technique is used otherwise the fracture may be obscured by the surrounding root structure;
It appears as a thin radiolucent line that may widen with time;
Vertical: teeth pulled as the bacteria easily travel down it.

Question 28

Luxation:

Answer 28

abnormal displacement of teeth, teeth should be evaluated using a PA to view the bone, pulp and PDL involved

a. Intrusion: tooth gets displaced into the bone    b. Extrusion: tooth gets displaced out of bone

Question 29

Avulsion:

Answer 29

the complete displacement of a tooth from the alveolar bone
A radiograph (PA) should be used to view the socket area (splintered bone may be present

Question 30

External Resorption: seen along the periphery of the root surface

Answer 30

Associated with:
Re-implanted teeth, abnormal mechanical forces, trauma, chronic
inflammation (perio), tumors, cysts, impacted teeth, or is idiopathic
no treatment

Question 31

Internal Resorption: involves the pulp and dentin of the crown/root

Answer 31

Precipitated by trauma,
pulp capping, pulp polyps;
root canal or extraction

Question 32

Pulpal lesions

Answer 32

Pulpal Sclerosis:
Calcification of the pulp chamber resulting in decreased size
1. Associated with aging
2. No clinical features or symptoms, only becomes a problem if RC is needed
Pulpal Obliteration:
Complete obliteration of the pulp & replacement w/ 2nd dentin
Non vital tooth and no treatment is needed
Secondary dentin is laid down in response to attrition, caries, restorations, trauma, abnormal mechanical forces, etc.)
Pulp Stones:
Calcifications found w/in the pulp
Cause is unknown
Appears radiographically as rounded radiopacities w/in the pulp (vary in size)
Asymptomatic and do not require treatment

Question 33

Five basic rules for bisecting technique

Answer 33

1. receptor must cover the prescribed area of interest
2. receptor must be positioned with one eighth of an inch extending beyond incisal or occlusal surfaces
3. central ray must be directed perpendicular to the imaginary bisector that divides the angle formed by the tooth and the receptor
4. central ray must be directed through the contact areas between teeth
5. x-ray beam must be centered over the receptor to ensure that all areas of the receptor are exposed