CH 24

Question 1

Caries formation

Answer 1

Acid from bacteria destroys (demineralizes) tooth structures
Demineralization leads to less dense enamel/dentin
Less dense structures allows more x-rays to pass through
Demineralized areas appear radiolucen

Question 2

Detection of caries

Answer 2

40-50% of calcium and phosphorus in teeth must be destroyed to be able to see caries on radiographs. This means: caries are always more destructive than they look in the image. Small, incipient caries are difficult to detect. Correct horizontal angulation is the most important factor. Control panel settings.

Question 3

Interproximal caries

Answer 3

Usually, can not be detected with clinical exam need rads, begin at the contact point or just below the contact. Triangular shaped (begins as notch)

Question 4

C-1 incipient

Answer 4

Caries penetrates less than 1/2 way through the enamel. Presents as a notch

Question 5

C-2 moderate

Answer 5

Caries penetrates more than 1/2 way through the enamel but not into the dentin. Triangle pointing toward pulp

Question 6

C-3 advanced

Answer 6

Caries penetrates fully through enamel and less than 1/2 way through dentin. Triangle in enamel and second triangle or notch in dentin

Question 7

C-4 severe

Answer 7

Caries penetrates fully through enamel and more than 1/2 way through dentin. Triangle in enamel and second triangle in dentin or triangle in enamel and diffuse readiolucency in dentin. If caries are visible on BWX, take a PA

Question 8

Occlusal caries

Answer 8

Clinical exam is preferred method of detection. Occlusal caries are not seen radiographically until DEJ is involved. C1 and Clare not visible on radiographs
C3 and C4 can be seen

Question 9

Buccal/lingual caries

Answer 9

Clinical exam is preferred method of detection, not seen radiographically until DEJ is involved, begin on facial or lingual surface and appears as a radiolucent circle. C1 and C2 not seen on radiographs C3 and C4 are indistinguishable.

Question 10

Cemental caries

Answer 10

Clinical exam is preferred method of detection. Occurs on roots of teeth (below enamel), recession must be present for buccal/lingual caries, cupped-out or crater-shaped below CEJ, do not confuse with cervical burnout. C1 and C2 are not seen on rads. C3 cratered radiolucent roots. C4 not indistinguishable from C3

Question 11

Recurrent caries

Answer 11

Occurs under restorations or around margins, often occur due to improperly placed restorations (poor prep or margins), radiolucency under restorations.

Question 12

Rampant caries

Answer 12

Spreading unchecked, typically seen in children with poor eating habits or adults with salivary flow issues

Question 13

Arrested caries

Answer 13

Caries no longer active, significant change happened. SDF/glass ionomer applied. Watch for changes.

Question 14

Conditions resembling caries

Answer 14

Radiolucent restorations, cervical burnout, Mach band effect, abrasion

Question 15

Nonmetallic restorations

Answer 15

If you have straight borders, defined borders, rectangular shaped = restorations. If you have a triangular shape pointed to the pulp, diffuse, not defined borders = caries.

Question 16

Cervical burnout

Answer 16

Optical illusion created when teh eye tries to distinguishes between white and black areas. Caused by cervical area (neck) of teh tooth and the surrounding structures. Enamel is radiopaque, alveolar bone is radiopaque, teh cervical area of teh tooth is less dense, do not confuse with root caries.

Question 17

Mach and effect

Answer 17

Optical illusion created when teh eye tries to distinguish between white and black areas. Caused by overlapped contacts. Dense radiopacity from overlapped enamel. Next to the overlap appears radiolucent lines.

Question 18

Abrasion

Answer 18

Wearing away of tooth surface with a foreign object. Root surface, do not confuse with cervical caries, abrasion is hard and smooth.