Class II Ag preps

Question 1

Where do class II lesions initiate?

Answer 1

at the area cervical to interproximal contact

Question 2

Qualities of an ideal radiographic examination

Answer 2

• dark density and good contrast
• sharp
• paralleling techniques (less distortion)
• minimal overlap

Question 3

pdl stands for

Answer 3

periodontal ligament

Question 4

Between the gingival and pulpal floors runs the ____ ___

Answer 4

axial wall

Question 5

Damage to adjacent tooth by the operator is called

Answer 5

iatrogenic damage

Question 6

What amount of clearance is necessary in class II preps?

Answer 6

0.5mm B. L and gingivally

Question 7

Why reverse S curve?

Answer 7

allows enough bulk for resistance for and leaves no unsupported enamel

Question 8

Why do we drop a gingival box in class II preps?

Answer 8

because if the entire floor of the prep was dropped as deep, the pulp woul be perforated

Question 9

Resistance form of class II preps

Answer 9

• pulpal and gingival floors are smooth and flat, PERPENDICULAR TO FORCES DIRECTED ALONG THE LONG AXIS OF THE TOOTH
• restricting extension of the proximal walls to maintain strong cusp and triangular ridges and maintain sufficient dentin support
• restricted occlusal outline form to areas receiving minimal occlusal contact
• Reverse S curve optimizing strength of amalgam and tooth structure at the junction of the occlusal and proxima box
• slight rounding of internal line angles to reduce stress concentration (bevel AXIOPULPAL line angle)
• providing bulk thickness for amalgam

Question 10

Beveling is done with what tool?

Answer 10

margin trimmer

Question 11

What tool used to create axio-gingical groove

Answer 11

margin trimmer

Question 12

What features increase retention form in class II preps?

Answer 12

• occlusal convergence (2-6 degrees)
• dovetail present
• axiogingival wall undercut

Question 13

Preps with wide (B-L) proximal boxes require what secondary retention measure?

Answer 13

• retention locks places along axiolingual and axiofacial line anges and parallel to the DEJ (0.2mm away)
• 0.5mm into dentin
• increase restoration fracture strength

Question 14

Convenience form in class ii

Answer 14

verify isthmus and clearance. Is there enough access for restoration and condensation?

Question 15

6 features of a class ii prep

Answer 15

1. appropriate isthmus width
2. 90-100 degree cavosurface margins
3. Reverse S curve
4. flat gingival floor/box
5. appropriate extensions into carious fissures
6. acute axiogingival wall