Ideal Class II Preps, Bases, and Liners

Question 1

What is done in the initial stage of prep design?

Answer 1

Outline form and initial depth
Resistance form
Retention form
Convenience form

Question 2

What is done in the final stage of prep design?

Answer 2

Removal of any remaining enamel pits and fissures, infected dentin, or old restoration
Pulp Protection
Secondary retention and resistance form
Finish enamel walls
Cleaning, inspecting, conditioning

Question 3

Resistance form definition

Answer 3

Shape and placement of the cavity walls that enable the tooth to withstand forces in teh long axis of the tooth

Question 4

Retention form definition

Answer 4

Shape or form that resists the displacement/removal of the restoration from tipping or lifting forces

Question 5

Convenience form definition

Answer 5

The shape or form that makes prepping the cavity (observing and accessing) the easiest

Question 6

What are the functions of the of the Dentin-Pulpal complex?

Answer 6

Formative - 1’ and 2’ dentin
Defensive - repairative dentin
Nutritive - supplies vital cells
Sensory - protective

Question 7

T/F - The only sense to stimuli the Dentin-Pulpal complex recognizes is pain

Answer 7

True

Question 8

Describe the Hydrodynamic Theory of Pain

Answer 8

Micromovement of fluid in tubules affect nerves

Can sense osmolarity, thermal, and pressure changes, dessication, and high-speed cutting

Question 9

What are the three Pulp Statuses that are diagnosed?

Answer 9

Vital
Pulpitis (reversible and irriversible)
Necrotic

Question 10

What are the ways to diagnose pulpitis?

Answer 10

Patient symptoms
Radiographic
Clinical tests

Question 11

What are the characteristics of tooth pain we should ask about?

Answer 11

Intensity
Location
Cause of onset
Duration
Painful when patient bites?

Question 12

What are the clinical methods to test pulp status?

Answer 12

Hot/Cold
Electric Pulp Test
Percussion test

Question 13

What is one of the most common forms of tooth pain?

Answer 13

Pulpitis

Question 14

What is the hallmark sign of Irreversible pulpitis?

Answer 14

Sensitivity to heat and not cold

Question 15

What is the sign of necrotic pulp?

Answer 15

No response to stimuli

Question 16

Why do we use liners and bases?

Answer 16

To protect the pulp from and minimize post-op sensitivity
Acts as a chemical, thermal, electrical, mechanical, barrier
Controls inflammation of pulp
Controls fluid movements

Question 17

Liner definition

Answer 17

Relatively thin layers of material used primarily to provide a barrier to protect dentin from fluids and residual reactants of the restoration
They contribute to the initial electrical insulation, generate thermal proteciton, and provide pulp Tx

Question 18

What are the different types of Liners?

Answer 18

Solution Liners
Suspension Liners
Cement Liners
Eugenol Liners

Question 19

Solution Liners

Answer 19

2-5 um
Name = Copal Varnish
Adhesives

Question 20

Suspension Liners

Answer 20

20-25 um
Name = CaOH2
Trade name = Dycal

Question 21

Cement Liners

Answer 21

200-1000 um
Name = GI
Trade name = KetacCem

Question 22

Eugenol Liners

Answer 22

Name = ZOE and B&T

Trade name = ZOE and B&T

Question 23

Base definition

Answer 23

Provides thermal protection and to supplement mechanical support for the restoration by distributing local stresses from the restoration across the underlying dentinal surface
Provides thermal protection of pulp
Provides mechanical retention for the restoration

Question 24

What is considered ‘Mild caries’?

Answer 24

Remaining Dentin Thickness >2.0mm

Question 25

How do we treat Mild caries?

Answer 25

Line with copal varnish and fill with Amalgam

Question 26

What are the different types of Bases?

Answer 26

ZnPo4 cement
ZOE reinforced cement
Polycarboxylate cement
GI cement
RMGI (most common)

Question 27

What is considered ‘Moderate Caries’?

Answer 27

0.5-2.0 Root dentin thickness

Ideal prep does not remove all caries

Question 28

How do we treat Moderate Caries?

Answer 28

Extend prep laterally until DEJ is noncarious
Remove carious dentin
Line with copal adhesive and fill with amalgam

Question 29

Wha is considered Severe Caries?

Question 30

What do we need to do when treating severe caries?

Answer 30

Pulp cap

Question 31

What are the different pulp caps

Answer 31

Indirect pulp cap - do if there is near pulp exposure

Direct pulp cap - do if there is pulp exposure

Question 32

Reparative dentin forms

Answer 32

15 days = cells differentiate
30 days = reparative dentin seen microscopically
100 days = reparative dentin seen radiographically

Question 33

How do you mix ZnPO4 cement?

Answer 33

Few drops of liquid and powder divided into equal increments
Add increments one at a time until proper consistency is reached
Mix on a glass slab to reduce heat (which would cause premature hardening)
Increase the amount of powder added when using it as a base to improve strength

Question 34

T/F - We don’t want to use ZnPO4 with composite

Answer 34

True - it inhibits polymerizaiton

Question 35

Why are GIs replacing ZNPO4s?

Answer 35

Adheres to tooth better
F release
Proven clinical record
Dimensionally stable
Biocompatable
Don't need to varnish GIS

Question 36

CaOH2 Liner

Answer 36

Equal portions of two pastes and apply to a clean, dry prep
Proceeds by an acid base rxn
Ca crosslinks phenol groups
Stimulates reparative dentin
Highly soluble (10-30% loss over 10 years)

Question 37

T/F - if you use a rubber dam, you have a much better chance at saving a tooth

Answer 37

True

Question 38

What factors help predict prognosis?

Answer 38

Size of the exposure
Tooth symptoms
Hemorrhage control
Field cleanliness
Sealing the access