Post Retained Crowns Treating Endodontically Restored Teeth Flashcards
What is usually different about root filled tooth?
Extensive coronal damage +/- lack of tooth tissue, loss of radicular dentine associated with endodontic treatment, and general long term prognosis less favourable
What are considerations of endodontically treated teeth?
Restorability assessment, resistance to tooth/root fracture, and retention of core and final restoration with dental tissue remaining
What are options for restoring endodontically treated teeth?
Direct restorations, indirect extra-coronal restorations, and post-retained crowns
What happens with decreasing available alternative options?
Extraction
What is a post-retained crown?
A crown which relies for its retention, mainly, on a post which is inserted into root canal system of a root filled tooth
When is a post-retained crown indicated?
When remaining coronal tooth structure is not sufficient for direct retention
Why is a post-retained crown indicated?
To provide extra retention for crown restoration
What should be provided for root-treated posterior teeth?
Some form of cuspal coverage (unless endodontic access is only coronal tissue lost)
What can placing posts result in failure from?
Iatrogenic perforation/root fracture/cement failure
Why do the majority of root filled teeth fail?
Restorative reasons such as non-restorable caries and root fracture rather than endodontic failure
How do you decide whether to restore endodontically treated teeth?
Extent of coronal damage and tooth type, functional demands
Why are posts required in severely broken down teeth?
To improve retention of core material
What significantly improves prognosis in posterior root-filled teeth?
A cast restoration with occlusal coverage/full coronal coverage
What is prognosis for anterior root terated teeth not necessarily improved with?
Crown placement
What is general treatment planning for post crowns?
Assess restorability, assess root treatment status, assess periodontal condition, and assess occlusal relationship
How do you assess restorability?
Clinically prior to embarking on root canal treatment, examine and if appropriate remove caries and assess degree of coronal breakdown
How do you assess root treatment status?
Symptoms, clinical signs, and radiographs
How do you assess periodontal condition?
Mobility and support
How do you assess occlusal relationship?
Study models
What radiographs are indicated in treatment planning for post crowns?
Intra-oral periapical and OPT depending on clarity
How does an intra-oral periapical aid to diagnosis?
Status of periapical tissues, status of root filling, status of periodontal tissues, and root length/morphology
What are stages of deciding whether to re-root treatment or not?
Ensure tooth is restorable first (assess current status), assess for signs and symptoms of ongoing disease clinical and radiographically, undertake (re)root canal treatment if needed then…, start restorative phase quickly to avoid risk of coronal microbial leakage, and proceed with crown/post retained crown ASAP to secure a coronal seal
How do the different post types differ?
Post shape, active/passive fit, surface characteristics, material, and fabrication method
What are the different post shapes?
Parallel/tapered/hybrid
What are the different surface characteristics?
Smooth/serrated/threaded
What are the different materials?
Metal/fibre