Gaining Access & Removal of Carious Tissue

Question 1

What type of disease is dental caries?

Answer 1

Reversible but progressive disease

Question 2

What tissues are affected by dental caries?

Answer 2

Affecting dental hard tissues

Question 3

What bacteria initiates dental caries?

Answer 3

Initiated by bacteria in a plaque biofilm

Question 4

What causes the demineralisation of the inorganic component of the teeth?

Answer 4

Fermenting carbohydrates produced by the carious bacteria produce acid which causes demineralisation

Question 5

What causes the destruction of the organic component of the teeth?

Answer 5

Proteolytic destruction of organic component

Question 6

What are some isolation techniques used when removing carious tissue? (4)

Answer 6

• Rubber dam
• Cotton wool roll (children)
• Dry guards
• Aspiration (suction)

Question 7

What are the ideal conditions when detecting caries on a tooth? (6)

Answer 7

• Good vision with magnification
• Good illumination
• Clean tooth surface
• Examine tooth when both wet and dry
• Use a round explorer (not sharp)
• You need TIME!!!

Question 8

Where are the 3 main sites of caries development?

Answer 8

• Pits & fissures/cingulum
• Approximal below contact area between teeth
• Smooth surface (near gingival margin)

Question 9

Explain the histology of each ICDAS score (0-4)

Answer 9

0 - No/Minimal enamel demineralisation

1 - Enamel demineralisation outer 50%

2 - Enamel demineralisation inner 50% through to outer 1/3 dentine

3 - Demineralisation of middle to inner 1/3 dentine

4 - Demineralisation of inner 1/3 dentine towards pulp

Question 10

What do the scores made from bitewing radiographs mean in regards to radiolucency? (0-4)

Answer 10

0 - Sound on bitewing

1 - Radiolucency confined to enamel

2 - Radiolucency in enamel up to EDJ

3 - Radiolucency in enamel and outer half of dentine

4 - Radiolucency in enamel and reaching inner half of dentine

Question 11

Explain what site is being referred to in each of Black’s Classifications (I-V)

Answer 11

I - Pits and Fissures caries

II - Posterior inter proximal caries

III - Anterior inter proximal caries

IV - Incisal edge caries

V - Smooth surface caries

Question 12

What is one advantage and one disadvantage of bitewing radiographs?

Answer 12

• Good for inter proximal caries

- Less good for occlusal

Question 13

Which type of radiograph is good for showing occlusal caries?

Answer 13

Dental Panoramic Tomograph

Question 14

What radiographs are taken for assessing apical status of a tooth?

Answer 14

Periapical Radiographs

Question 15

What does a sensibility test determine?

Answer 15

Testing the nerve supply

Question 16

How do you conduct a sensibility test? (3)

Answer 16

• Thermal test (whether or not tooth can feel hot/cold)
• Electronic pulp tester
• Test cavity

Question 17

Explain the steps of the operative phase of caries management (5)

Answer 17

• Gain access
• Identify sound and carious tissue
• Excavate caries
• Modify cavity for restorative material
• Restore

Question 18

What is the importance of enamel preparation when dealing with a carious legion? (3)

Answer 18

• Gain access to full extent of lesion
• Remove demineralised and unsupported enamel
• Create sound peripheral margin to seal with restorative material

Question 19

What is the sequence of dentine removal?

Answer 19

• Identify caries-infected vs caries affected vs sound dentine with a probe
• Identify peripheral extent of caries to EDJ
• Excavate caries from EDJ (clear periphery of lesion)
• Move towards pulp from periphery

Question 20

What is the retention property of a cavity?

Answer 20

Property of a cavity to resist displacement of the restoration in the direction of its placement

Question 21

What is the resistance property of a cavity?

Answer 21

Property of the cavity to resist displacement of the restoration in any other direction

Question 22

What are some other methods of caries removal? (4)

Answer 22

• Air abrasion
• Cavitron
• Carisolv
• Lasers