ON FINAL: Restoration of Endodontically Treated Teeth: Posts and Cores Flashcards
The teeth become ________ and more susceptible to decay, fracture, and breakdown
softer
How do you decide what restoration to put on an endodontically treated tooth?
- Must have a ”global” perspective on your patient
- Evaluate the existing root canal
- Evaluate if the tooth is restorable
- Evaluate how important is this tooth in the patients overall treatment plan
- Evaluate how important this tooth is in the patients functioning
- What might be needed to properly restore this tooth beyond a crown? (post, core, crown lengthening, ortho)
What do you need to look for when evaluating the adequacy of the root canal?
- Is the tooth asymptomatic?
- Are the canals well filled?
- Does the apex appear sealed?
- Is there any suspicion of apical pathology?
- Is there a temporary restoration present?
- Is any restoration present sealed protecting the RCT from the oral environment?
- How long has the present restoration been
present? - Long standing temporary or lack of proper seal from restoration?
- Deep caries present
What do you need to think about when treatment planning a crown for an endo tooth?
- Is the tooth to be restored in a useful function in the patient’s occlusion?
- What is the prognosis of the restoration you want to place on the RCT treated tooth?
- Is the patient a bruxer? Grinder?
- Is the patient home care adequate?
Why do we need to examine RCT teeth more carefully and consider crowning RCT teeth quickly?
- Once pulp has been removed, and nerve sensation stopped, the tooth loses its ability to monitor changes in proprioception. Meaning you can bite harder on these teeth before you feel pain or discomfort.
- In an RCT tooth, there is a loss of structural integrity from a variety of sources (access, caries, bone loss from infection).
What is a favorable tooth fracture?
- Fracture in enamel only (crack line) or fracture in enamel and dentin
- The fracture line does not extend apical to the cemento-enamel junction
- There is no associated periodontal probing defect
- The pulp may be vital requiring only a crown
- If pulp has irreversible pulpitis or necrosis, root canal treatment is indicated before the crown is placed
What is a questionable tooth fracture?
- Fracture in enamel and dentin
- The fracture line may extend apical to the cemento-enamel junction but there is no associated periodontal probing defect
- There is an osseous lesion of endodontic origin
What is an unfavorable tooth fracture?
- Fracture line extends apical to the cementoenamel junction extending onto the root with an associated probing defect
Posterior tooth fractures occur because:
- Greater occlusal forces
- Divided occlusal surface (Cusps and Fossa)
- Fillings weaken tooth ability to hold together
In posterior teeth occlusal forces more inline with vertical axis of tooth. Therefore, __________
fractures more likely
vertical
Crowns did or did not significantly improve the success rates of endodontically treated ANTERIOR teeth when ample tooth structure remains?
DID NOT
Crowns significantly improved success rates of endodontically treated ____________ teeth
POSTERIOR
Crowns should be placed on RCT Treated POSTERIOR teeth…
as soon as possible with few exceptions
Crowns are only indicated on RCT Treated ANTERIOR teeth when:
- They are structurally weakened by large or multiple restorations
- They need substantial changes in form or color that cannot be achieved by more conservative means
A crown needs at least ___mm for a ferrule.
2
What are the advantages and disadvantages of amalgam as a core material?
- Disadvantage – not retentive, does not bond, more tooth reduction needed
- Advantage – strength
What are the advantages and disadvantages of composite as a core material?
- Disavantage – not as strong
- Advantage – usability, bonding, more conservative tooth reduction
If tooth structure is missing, and restorability is compromised but not condemned, a _____ can be used to add strength to the core build up as you restore the lost tooth structure
post
Does a post increase the strength of a tooth?
NO
- adds support
Why do we use a post?
- When RCT teeth have inadequate tooth structure to retain a core
- In teeth that have lost more than 50% of coronal tooth structure
- In single rooted teeth since the anatomy of the pulp chamber does not offer mechanical retention for a build up
- In teeth with significant response to lateral forces of occlusion
When do you not use a post?
Preparation of a post space adds risk to the restorative prognosis
- Higher likelihood of fracture or perforation
- Narrow roots
- Curved roots
The purpose of a post is to…
retain the core in a tooth when there is extensive loss of coronal tooth structure
If an anterior tooth has darkened due to RCT what can you do?
- you can try internal bleaching
- possible veneer or composite
What is the process for internal bleaching?
- In access hole, place bleaching material and seal the access with a temporary fill
- May need to be repeated several times
- Can last for a reasonable amount of time and may need to be touched up in the future