Restoration of Root filled teeth Flashcards
(14 cards)
What are some reasons root treated teeth are weaker than vital teeth?
- reduction in proprioception
- NaOCl denatures collagen
- Ca(OH)2 reduces flexural strength of dentine
- Often structurally damaged prior to RCT
- Occlusal access reduced tooth stiffness
What are the purposes of coronal restorations?
- protection of remaining fragile tooth structure
- coronal seal to prevent bacterial ingress
- favourable loading in function
What features are associated with successful restoration of the root filled tooth?
- remaining tooth structure
- pattern of remaining coronal tooth structure
- provision of cuspal coverage for posterior teeth
- use of tooth as abutment for denture or bridge
- occlusal forces
What are the different types of coronal restoration?
- direct composite
- direct amalgam +/- nayyar core +/- cuspal coverage
- onlay/inlay with cuspal coverage
- full coverage crown
- endo crown
- fibre post and composite core
- post + core + crown
What is the main reason for failure of a well placed direct composite?
vertical fracture
Why is it important to ensure the GP has a good seal?
provides a physical barrier to stop bacterial ingress if the coronal restoration leaks or is lost
What does the PECOFA acronym stand for when assessing restorability?
Perio prognosis
Endo prognosis
Coronal tooth structure remaining
Occlusal space
Functional requirement
Aesthetic requirement
Give two indices that can be used to assess the restorability of a tooth
Dental Practicality Index (2017)
Tooth Restorability Index (2005)
What is the Tooth restorability index?
divide tooth into 6 sections of pie
score each slice depending on the amount of remaining coronal tooth structure
What is a disadvantage of posts?
weakens teeth
When is a post retained crown provided?
where there is insufficient coronal dentine to support a crown
(predictably restores a tooth with over 50% coronal tooth structure)
What is a Nayyar core?
2-4mm of GP is removed from canals
amalgam packed in
crown or cuspal coverage over the top
What is the ferrule?
sufficient supra-gingival dentine around the circumference of the tooth that enables the margins of the extra coronal restoration to sit on the sound tooth tissue without encroaching on the biological width
What should the ferrule be?
2mm minimum
