Principles and Techniques of Class II Composite Preparations in Restorative Dentistry 낱말 카드

What are the two types of Class II preparations?

Simple (one surface) and Compound (at least two surfaces)

What is the ideal Class II preparation?

Conventional amalgam cavity preparation

What is a slot Class II preparation?

A preparation that accesses proximal caries from the occlusal surface

What is the purpose of the Marginal Preservation Technique?

To maintain the integrity of the marginal ridge while accessing caries

Why is conventional Class I preferred over box preparation?

Amalgam requires maximum mechanical retention and decay may extend to pits and fissures

What is essential for case selection in box preparation variation?

Confidence that there is no occlusal decay in the fissures

What does Class II preparation consist of?

Class I preparation plus a proximal box

What are the components of a proximal box?

Buccal wall, axial wall, gingival floor, and lingual wall

What is the first step in performing a Class II preparation?

Define the outline of Class I

How do you mark the midpoint for Class II preparation?

Mark the midpoint on the mesial/distal contact

What is the ideal depth for Class II preparation?

Start at approximately 1.3 mm and finalize at 1.5-1.75 mm

What is the significance of dropping the box past the contact?

To ensure decay is removed, particularly cervical to the interproximal contact

What is the recommended clearance for the gingival extension?

0.5 mm minimum clearance

What is the purpose of refining the box with an 8/9 hatchet?

To remove unsupported enamel on the gingival floor

What is the goal of creating a reverse S-curve in Class II preparation?

To preserve the cusp and create a 90-degree exit angle at the cavosurface margin

What can happen if weak enamel margins are not removed?

It can lead to compromised structural integrity of the restoration

What are the dimensions for buccal and lingual extensions in proximal box preparation?

Clearance of approximately 0.3 - 0.5 mm with convergent walls

What is the depth requirement for axial extension in premolars?

1 mm to 1.2 mm

What is the depth requirement for axial extension in molars?

1.5 mm

What is the gingival floor depth from the adjacent marginal ridge?

3 mm with 0.5 mm gingival clearance

What is the role of tapered burs in Class II preparation?

To refine the box and remove unsupported enamel

What is the final shape of the proximal box?

Trapezoidal