Operative Final Exam - Readings

Question 1

What is enameloplasty?

Answer 1

when you modify the enamel of a tooth’s surface to make it easier to clean and remain caries-free; this could occur if there is a deep fissure/pit, etc.

*NOTE: it does not extend the outline form of a prep, it is just carves away no more than 1/3 of the enamel at the surface

Question 2

What are the principles of outline form and initial depth?

Answer 2

• all unsupported or weakened enamel should usually be removed
• all faults should be included
• all margins should be placed in a position to allow finishing of the margins of restoration

Question 3

What are the features of establishing proper outline form and initial depth?

Answer 3

• preserving cuspal strength
• preserving marginal ridge strength
• minimizing faciolingual extensions
• connecting two close (<0.5 mm) defects or tooth preparations
• restricting the depth of the preparation into dentin

Question 4

What are the principles in obtaining primary resistance form?

Answer 4

• using a box shape with a relatively horizontal floor which helps the tooth resist occlusal loading
• restricting the extension of the external walls to allow strong cusp and ridge areas
• slight rounding of internal line angles to reduce stress
• reducing and covering weak cusps
• providing enough thickness of restorative material to prevent fracture
• bonding the material to tooth structure when appropriate

Question 5

What are the features of primary resistance form?

Answer 5

• relatively horizontal floor
• box-like shape
• inclusion of weakened tooth structure
• preservation of cusps and marginal ridges
• rounded internal line angles
• adequate thickness of restorative material
• reduction of cusps for capping, when indicated

Question 6

What is a feature of primary retention form for an amalgam restoration?

Answer 6

external tooth walls that converge occlusally

Question 7

What are the two types of secondary retention and resistance forms?

Answer 7

• mechanical preparation features

- treatments of the preparation walls with etching, priming, and adhesive materials

Question 8

What are the 3 prerequisites for amalgam success?

Answer 8

• 90 degree junctions of amalgam with tooth structure
• mechanical retention form
• adequate thickness for the amalgam material