Manual 2: advanced cavitated carious lesions Flashcards
in which two cases do we start restorative interventions?
- cavitated lesion is non-cleanable
- cavitated lesion can no longer be sealed
what are top three priorities when restoring?
- preserving healthy and remineralisable tissue
- achieving a restorative seal
- maintaining pulpal health
what is the main objective of carious tissue removal? how is this objective achieved?
- aim: long lasting restoration
- achieved by providing enough spoke for restorative ,material and having clear peripheral margins for better seal/adhesion.
why do we not remove bacterially contaminated/ demineralised tissue close to the pulp?
- to prevent pulpal stress/damage
what is the difference between the new process of selective caries removal and the old non-selective caries removal?
- selective caries removal aims to disrupt biofilm and seal lesion, denying them access to nutrients from oral environment, causing lesion to arrest.
- non-selective caries removal relied on removing the whole carious tissue and then filling. This removed unnecessary amount of potentially remineralisable tissue and increased risk of pulp exposure.
when is restoration longevity more important and when is preserving pulpal health more important?
shallow/ moderately deep lesions, restoration longevity is priority:
- selective caries removal to firm dentine is caries out ( leaving ‘leathery’ dentine at the base which feels resistant to hand excavator )
Deeper lesions, priority Is preserving pulp health
- in primary/permanent, selective removal to soft dentine should be removed so more carious dentine is kept at the base of the cavity compared to a shallow lesion.
- in permanent teeth, stepwise removal is an option
What are the key things that must be done for all cavity preparations?
- Cavity margins (peripheral dentine) are left hard/scratchy after removal: maximises retention of restorative material on good quality dentine and better seal.
- carious tissue is only left at the base of the cavity, over the pulp to avoid pulp exposure and stress, promoting pulpal health
When do you do selective removal to firm dentine ?
- in shallow /moderately deep lesions
When do you do selective removal to firm dentine ?
- in deeper lesions
outline the method of cavity preparation / selective caries removal
• examine tooth
• Administer LA - likely to remove dentine
• isolate tooth - moisture control: cotton wool, dry guard, saliva ejector
• Place rubber dam, best to isolate tooth distal to one operating on.
• Locate carious lesion
• access lesion using high speed with diamond fissure bur
◦ cavity shape based on extent of lesion
◦ the width of cavity dependent on extent of carious lesion within ADJ
◦ the depth of cavity dependent on texture of dentine
• Drill the tooth until you have got clear margins, so peripheral dentine is hard.
• Remove loose, soft carious dentine with slow speed rose-head bur
• stop removing when the texture is sticky, can check with probe in between
• the base of the cavity must have carious dentine left to protect pulp
outline the method of restoring with composite following cavity preparation.
• May use cavity liner initially to protect pulp from toxic effect of restorative material
• etch the tooth
◦ Etch enamel for 10 seconds
◦ Then, etch enamel and and dentine together for further 10 seconds
• Suction the acid etch
• rinse the acid etch off the tooth
• dry the tooth, careful not to remove the soft dentine at base of cavity
• apply bonding agent to the tooth
• gently air thin bonding agent
• light cure
• fill cavity in small increments with composite
• Light cure after each increment
• when done, check restoration seals the tooth
• adjust for aesthetics and function using composite finishing burs and disc
what do you do after restoring the tooth?
- remove rubber dam using forceps
- check occlusion with articulating paper
- floss contacts
- polish
