L15 Management of Dental Caries Lesions

Question 1

What are the major aims of minimally invasive dentistry?

Answer 1

• Remineralisation of early lesions
• Reduction of cariogenic bacteria to eliminate risk of furhter demineralisation and cavitation
• Minimal surgical intervention of cavitated lesions
• Gaining disease control

Question 2

How can a cleansable lesion be arrested?

Answer 2

Through biofilm control alone (OHI).

Question 3

What interventions can a dentist offer in the management of cleansable carious lesions?

Answer 3

• Dietary assessment and tailored adivce
• Fluoride varnish (2.2% NaF) applied twice a year
• Prescribe daily fluoride mouthwash to be used at alternative time to brushing
• Prescribe 2,800-5,000ppm fluoride toothpaste

Question 4

When should a carious lesion be restored?

Answer 4

• There is certainty that the lesion is progressing and cannot be arrested
• Tooth is symptomatic (painful)
• There are aesthetic considerations
• The surface is needed for oral function (mastication)

Question 5

What are the 3 no removal of carious dentine techniques for carious lesion management?

Answer 5

• Fissure sealant
• Hall technique
• Non-restorative cavity control

Question 6

What are the 5 removal of carious dentine techniques for carious lesion management?

Answer 6

• Atraumatic restorative treatment (ART)
• Selective removal to soft dentine
• Selective removal to hard dentine
• Stepwise removal
• Non-selective removal to hard dentine

Question 7

Describe fissure sealants.

Answer 7

• For non cavitated enamel and dental lesions in pits and fissures
• Prevents entry of bacterial substrate into lesion and prevents progression
• “Trampoline effect”- enamel is hard and brittle, dentine is soft- eventually enamel may wear away and lead to failure
• Only suitable for shallow lesions, code 2 or less

Question 8

Describe the Hall technqiue.

Answer 8

• Used for children
• Separators placed either side of tooth
• 2nd appointemnt: steel crown placed over tooth
• Crown cemented with glass ionomer cement

Question 9

Describe non-restorative cavity control.

Answer 9

• Non-cleansable lesions can be widened to enable cleansing
• In children this may be used as a definitive treatment
• In adults it may be used prior to restoration to halt disease progress and conserve dentine

Question 10

What are the principles of carious tissue removal?

Answer 10

• Preservation of non-demineralised and remineralisable dental tissues
• Provision of sound cavity margins to achieve a good peripheral seal and prevent entry of bacteria and substrates
• Maintain pulpal health by preserving residual dentine and avoiding pulp exposure

Question 11

Describe soft dentine.

Answer 11

Will deform when a hard instrument is placed into it, easily removed with an excavator.

Question 12

Describe leathery dentine.

Answer 12

Does not deform when a hard instrument is pressed into it, can be easily removed with an excavator.

Question 13

Describe firm dentine.

Answer 13

Resistant to hand excavation, some pressure required.

Question 14

Describe hard dentine.

Answer 14

Pushing force required, requires sharp cutting edge or bur, makes a scratchy sound when firmly stroked with dental probe.
Healthy dentine.

Question 15

Describe the zones of carious dentine.

Answer 15

• Necrotic zone
• Contaminated zone (bacterial penetration)
• Demineralised zone (no bacteria, but does contain acids produced by bacteria)
• Sclerotic dentine (translucent zone)
• Tertiary dentine

Question 16

Outline atraumatic restorative treatment (ART).

Answer 16

• Uses hand instruments
• Special care dentistry, paeds, domiciliary visits
• Removal of carious enamel and dentine to firm tissue
• For deep cavities, tissue removed till dentine is soft
• Restoration and fissure seal with high viscosity glass ionomer cement

Question 17

Outline selective removal of carious tissue (to firm or soft dentine).

Answer 17

• Most common technique
• Create a cavity periphery of sound enamel and hard dentine (scratchy sound)

To firm dentine: for lesions in outer 2/3rds of dentine with no risk of pulp exposure, axial wall hard dentine

To soft dentine: for severe caries in inner third of dentine with risk of pulp exposure, axial wall still covered in soft dentine

Question 18

Outline stepwise removal.

Answer 18

• Based on the principle that lesions can resolve themselves
• Suitable for soft, deep carious lesions with large pulp chambers (younger people)
• App 1: remove tissue in enamel and selective removal in dentine, 2-3mm from pulp, temporary dressing of up to 12 months placed e.g. GIC
• App 2: patient returns 1 year later, remove GIC, tertiary dentine will have been produced so increased RDT, firm base for restorative material to be placed on top

Question 19

Outline non-selective removal to hard dentine.

Answer 19

• Only used in endodontics
• Very destructive
• Increases risk of pulp exposure and irritation due to reduced RDT

Question 20

What are the steps of selective caries removal.

Answer 20

1. Assessment and patient managaemnt
2. Access cavity
3. Establish clean periphery
4. Cavity modification
5. Manage carious dentine over pulp
6. Restore

Question 21

Describe how you would access a carious lesion in dentine for selective removal technqiue.

Answer 21

• Make a small opening in the enamel to visualise and instrument access to carious dentine
• Site and shape of access cavity in dentine is determined by size of lesion and visible change in tooth tissue

Question 22

Desribe how you would establish a clean periphery for selective removal technqiue.

Answer 22

• In the coronal portion, the periphery consists of enamel and any carious dentine at the ADJ, they should both be hard
• Entire periphery must be caries free
• When a cavity extends beyond the cementoenamel junction and onto the root surface, the periphery then includes any dentine right at the edge of the cavity

Question 23

Describe cavity modification for selective removal technique.

Answer 23

• Some cavities will require modification e.g. remove unsupported enamel, make sure internal line angles are rounded

Question 24

Describe how to manage carious dentine over the pulp for selective removal technique.

Answer 24

• Floor of cavity should be covered with stained but firm dentine
• Use excavator to remove soft, dry dentine, roll don’t dig
• Soft and wet dentine should be removed, preferably with stepwise technique

Question 25

Why is cavity depth important?

Answer 25

• In shallow cavities the depth may not allow sufficient bulk of restorative material for optimal strength, additional tooth tissue may need to be removed

Question 26

Describe 3 types of restoration following selective carious tissue removal.

Answer 26

• PRR: small composite, covered with fissure sealant (preventive resin restoration)
• Sealant restoration: small cavity restored with composite, restoration and remaining fissures fissure sealed
• Conventional class I: involves majority of the fissure pattern, nothing is left to fissure seal

Question 27

Why is moisture control important?

Answer 27

If the cavity is contaminated with moisture, bacteria in saliva can enter the newly exposed dentinal tubules and cause post-op sensitivity, the proteins in saliva can also coat the dentine surface and interfere with bonding agents.