9/11: Crown Preparation Flashcards
- What are the parts of a crown preparation?
a. Axial wall
b. Interproximal wall
c. Finish line
d. Occlusal anatomy
- A full coverage restoration can survive in the biologic environment of the oral cavity only if
a. Margins are closely adapted to the surface finish line
- The design of what dictates the shape and bulk of restorative material in the marginal area of the restoration
a. Finish line
- What are the types of finish line designs?
a. Knife edge
b. Chamber: light and heavy
c. Shoulder
d. Beveled shoulder
- The knife edge is primarily used for what kind of crowns?
a. Metal specifically gold crowns
- What marginal design is the most conservative?
a. Knife edge
- What are the disadvantages of the knife edge?
a. Difficult to see finish line
b. Metal can be thin and susceptible to distortion
c. Overbulking of crown material
- What are the indications for a knife edge margin?
a. Generally not indicated
i. Maybe tipped molar
- When should you use a light chamfer?
Metal crowns
Zirconia crowns
When should you use a heavy chamfer?
Ceramic crowns
Zirconia crown
Metal-ceramic crowns
- What bur should you use to create a chamfer?
a. Round ended
- Light chamber is how deep into axial wall?
a. 0.3-0.5mm
- The light chamfer produces what degree of margin?
a. 30-45 degree
- What finish work for every material?
a. Heavy chamfer
- How deep is a heavy chamfer?
a. 1-1.2mm
- A shoulder creates what degree angle?
a. Close to 90 degrees
- When should a shoulder be used?
a. Metal-ceramic crowns
b. All ceramic crowns
c. Zirconia crowns
- What finish is used for inlays and onlays?
a. Beveled shoulder
- What can be used for a metal ceramic crown that has a metal collar?
a. Shoulder with bevel
- This _______ finish line can prevent close adaptation of crown margin
a. Rough preparation
- If you have recurrent decay on the margin, what could be a possible cause?
a. Roughened finish line
- What is the disadvantage of the shoulder?
a. Marginal adaptation can be affected
- What gives you the best finish line for a ceramic crown?
a. Heavy chamfer
- A rise in pulp temperature by ___ degrees can significantly increase the chance of pulpal necrosis
a. 10 degrees
