Cariology

Question 1

What pH can dentine dissolve?

Answer 1

6.7

Question 2

Why does visual caries examination have low specifiticy

Answer 2

A number of dental conditions present clinically as changes in enamel colour/opacity/tecture/surface breakdwon

Question 3

What is the main difference between ICDAS 5 and 6?

Answer 3

5 is less than half the tooth. 6 is more than half.

Question 4

When would you do a prr over a fs?

Answer 4

When some cavitation has occured

Question 5

What are the goals of sealants?

Answer 5

1. Limit microbial adhesion and growth
2. Optiise cleansibility
3. Seal breached enamel

Question 6

How does etching increase bonding? (4)

Answer 6

• Increases surface area
• Creates voids in rods, and opens dentine tubules which can be penetrated
• Increased surface energy
• Removal of debris

Question 7

Why is a bevelled margin helpful for bonding?

Answer 7

Creates a more favourable orientation of the enamel rods

Increases surface area

Question 9

Is dentine bonding chemical or micromechanical with composite?

Answer 9

Both. Penetration into dentine tubules + Collagen coupling with the OH group in HEMA component of resin.

Question 10

Why is a primer needed?

Answer 10

Prevent collagen collapse

Question 11

Dental amalgam is an alloy of:

Answer 11

• Mercury
• Silver
• Copper
• Tin

Question 12

What are the categories of care on a tx plan.

Answer 12

A. STABILISATION

Primary - Emergency, Urgent

Secondary - Prevention, operative

B. REHABILITATION

C. MAINTENANCE AND MONITORING

Question 14

how many mm of clean margin do you need before getting to affected dentine?

Answer 14

2-3mm

Question 15

How long does it take to repair a porous white spot lesion with plaque control

Answer 15

2-3 weeks will become shiny and hard like normal enamel .

lesion underneath takes longer to repair.

Question 16

What is the golden triangle of minimally invasive dentistry

Answer 16

1. The histology of the dental substrate is being treated
2. Consideration of the practical operative techniques available to excavate caries minimally
3. The chemistry/handling of adhesive materials used

Question 17

What causes cracked cusp symptoms to appear?

Answer 17

Fracture progression

Question 18

When is cuspal overlay indicated (2)

Answer 18

• Less than 2mm width
• More than half the cusp is reduced

Question 19

How much material is required for composite cuspal overlay?

Answer 19

2mm

Question 20

How long should 37% etch stay on for?

Answer 20

30-60 seconds on enamel, 15 seconds on dentine

Question 21

Notes on primer:

Answer 21

• Monomer which acts as intermediate between hydrophilic dentine and phobic adhesive
• Dentine not too dry, not too wet
• Apply and agitate 20 seconds
  *

Question 22

What is the role of adhesive?

Answer 22

Resin extension which forms a hybrid layer

Question 23

How is the smear layer of dentine overcome?

Answer 23

Penetration with acidic monomer

Question 24

What is the shear bond strength of freshly prepared enamel?

Answer 24

20MPa

Question 25

What is the shear bond strength of freshly prepared dentine?

Answer 25

5-10MPa

Question 26

What level of bleach is needed fro non vital bleaching

Answer 26

35%

Question 27

2 reasons why non-vital teeth turn dark

Answer 27

* Trauma - internal bleeding * Cements used in RCT

Question 28

4 disadvantages of non-vital bleaching:

Answer 28

1. Results not always predictable 2. Risk of cervical root resorption 3. Risk of soft tissue buns 4. Reduce bond strength of enamel and dentine to composite resin

Question 29

4 advantages of night guard vital bleaching:

Answer 29

1. Easy application 2. Safety 3. Low cost 4. Successful in greater than 90%

Question 30

2 reasons why you should do non-aesthetic fillings before whitening:

Answer 30

1. Sensitivity 2. Hydrogen peroxide can reduce bond strength of composite resin

Question 31

* During opening, the muscle pulls the disc forward

Answer 31

Lateral pterygoid muscle (inferior attachemd)

Question 32

During closing, the muscle pulls the disc upward toward the slope of the joint

Question 33

What muscles are involved in mouth opening

Answer 33

* Lateral pterygoid (inferior) * Accessory

Question 34

What muscles are involved in mouth closing

Answer 34

* Temporalis * Masseter * Medial pterygoid * Lateral pterygoid (superior)

Question 35

What are the implications of group function on restoration?

Answer 35

* Posterior restorations will be under more loading so increased likelihood of fracture. * Tensile forces on composite as opposed to desired compressive force

Question 36

A contact that displaces a tooth, diverting the mandible from its intended path. Usually caused by high restoration or cusp.

Answer 36

Premature contact

Question 37

Any tooth contacts that interfere with or hinder harmonious mandibular movement is called

Answer 37

an Interference

Question 38

Blue articulating paper should be used for: Red should be used for:

Answer 38

* Blue for MI * Red for excursive

Question 39

How to do occlusion of fillings:

Answer 39

1. Get patient to bite up and down on blue and adjust until does not feel high. Should be point contact on cusp tips. 2. Get patient to chew on red paper, then bite up and down on blue. 3. Any marks that are blue and red - keep 4. Any marks that are red only - interferences - remove.

Question 40

Name 6 tips to reduce potential loading on teeth

Answer 40

1. Ensure axial loading 2. Load closes to the fulcrum 3. Flatten cusps 4. Control excursive guidance 5. Flatten occlusal planes 6. Material selection