Crown and bridges

Question 1

What does treatment planning inform the patient about?

Answer 1

Current conditions 
Extend of dental treatment proposed 
Time and cost 
Level of home care
Level of maintenance/repairs/replacement

Question 2

What does identification of patient’s needs involve?

Answer 2

Correction of existing disease
Prevention of future disease
Restoration of function
Improvement of appearance 
should conform to the patient's needs

Question 3

What are the available materials and techniques?

Answer 3

Plastic materials (amalgam and composite)
Cast metal
Porcelain
Metal ceramic 
Veneered composite
Fibre re-inforced composite 
CAD/CAM

Question 4

What is the definition of a crown

Answer 4

an indirect extracoronal restoration which replaces tooth structure and restores anatomy

Question 5

What are the indications for placing a crown?

Answer 5

Badly broken down or previously heavily restored teeth
Trauma
Tooth wear
Hypoplastic conditions and atypical shape
To alter occlusion
Part of another restoration
Restore missing function
Mechanical problems
Appearance

Question 6

what are contraindications?

Answer 6

Other more conservative restorative option are viable
Poor oral hygiene
Very broken-down tooth with subgingival caries
Periodontal condition - not enough bone support

Question 7

How do you carry out the history and examination for crown

Answer 7

Patient factors - age; younger have larger pulp, older more brittle teeth
Mouth condition
Tooth/teeth in question

Question 8

What patient factors need to be considered in crown planning in young patients

Answer 8

Size of pulps
Degree of eruption of the tooth
co-operation of the patient

Question 9

what are the general patient factors for crown planning

Answer 9

Attitude and expectation
Co-operation 
Age
Female patients - more concerned about appearance
Social history, occupation
Habits 
Cost

Question 10

What are the individual tooth factors that need to be considered when crown planning

Answer 10

Value of the tooth
Position of the tooth in the mouth 
Appearance
Pulp status 
Periodontium
Occlusion
Root length

Question 11

What are the 6 basic points of aesthetics

Answer 11

Colour
Contour
Outline
Symmetry
Proportion 
Soft tissue harmony

Question 12

How would you assess the pulp status?

Answer 12

Always check vitality prior to crown prep
15-20% of vital teeth will become non-vital following crown prep
Always take a pre-op periapical radiograph
Assess size and depth of current restorations

Question 13

Why is occlusion so important?

Answer 13

Anterior teeth determines the movement of the posterior teeth.
Failure to conform to, or create anterior guidance will upset posterior occlusion
Understanding and planning the occlusion is essential for success

Question 14

What are the different types of crowns?

Answer 14

Gold or metal - posterior
Metal ceramic or porcelain fused to metal (PFM)
Dentine bonded crown (ceramic)
High strength core all ceramic crown
Composite crown

Question 15

What is a bridge

Answer 15

Tooth-borne indirect prosthesis which is used for the replacement of one or more missing teeth

Question 16

What are the reasons for tooth loss?

Answer 16

Caries
Periodontal disease
Trauma
Hypodontia
Tooth wear
Oral cancer
Iatrogenic

Question 17

What are the different types of bridges

Answer 17

Fixed-fixed
Fixed-movable
Cantilever
Resin bonded
Implant retained

Question 18

What are the steps for planning for bridges?

Answer 18

History and examination
Critical thinking and decision making
Detailed planning of the bridges and performing clinical and laboratory stages
(similar to crown planning )

Question 19

What are the treatment options for partially edentulous patients

Answer 19

No prosthetic treatment - then have compromised function and aesthetics
RPD 
Conventional tooth supported FPD
Resin bonded bridge
Implant supported FPD

Question 20

What are the problems with conventional tooth supported FPD?

Answer 20

Invasive and irreversible approach
loss of enamel
Pulp damage but fixed and predictable solution, need to prepare the adjacent tooth

Question 21

What is the problem with resin-bonded bridge?

Answer 21

Conservative fixed option but risk of debond and some aesthetic issues

Question 22

How do you carry out a clinical examination

Answer 22

Assessing the abutment teeth 
Crown:root ratio
Radiographic assessment 
Length of span
Occlusion 
Shape of ridge

Question 23

How do you assess the abutment teeth

Answer 23

Periodontal assessment
Periapical assessment
Root configuration

Question 24

What is the max and minimum crown-root ratio

Answer 24

2: 3 optimum
1: 1 is the minimum

Question 25

How should the occlusion be assessed?

Answer 25

the occlusion of the abutment tooth/teeth should be assessed but also the occlusion of pontic with the opposing arch should be predicted

Question 26

How can the final appearance be predicted

Answer 26

use of study models and diagnostic wax ups
Temporary RPD
Reshaping of abutment teeth with composite and temporary attachment of pontic teeth

Question 27

What are temporary lab-made bridges used for?

Answer 27

To predict outcome
Allow further modifications for aesthetic reasons
Allow modifications to occlusion
Give time to soft tissues to heal and reshape before final restoration