W6 - Restoration of Badly Broken Down Tooth - Booth Flashcards
When is a broken down tooth non restorable
Ferrule effect
Occlusion
Sub gingival caries
Perio
Failing RCT
Root fracture
Poor access
Poor OH
How to assess badly broken down tooth (8)
Sensibility test
Quality of root filling
Radiograph
Frac finder
Pain / symptoms?
History of frequently failing restos
BPE/GPPC (perio - probe 6 times around dentition)
Study models
What is BPE?
Basic Periodontal Examination
- Probe 6 times around the sextants
Do pins work with composite?
No
- Tend to propagate cracks underneath pin hole
- Will fracture off a chunk of the composite
- Metal of pin shows through CR
Problem with open sandwich technique
GIC will wash out - will appear like caries on radiograph - composite overhanging
- Causes food/plaque trap
Only indicated for very deep subgingival/inaccessible restos
What can be used to improve direct restorations in non-vital teeth
Fibre posts
Nayyar core
Composite vs Amalgam
Single canal / anterior
Posterior / multirooted need cuspal coverage
Crown lengthening
What happens if core is bulky and post is thin?
Thin will lead to bending
Need to make interface wider between post and core
- Fill this space with composite after placing thicker fibre post
Why do posterior teeth need cuspal coverage
The further you prepare down apically, the higher the chance of fracture
Needs support
Will fracture otherwise
What can improperly placed pins lead to? (2)
Internal resorption - if close to pulp
Can cause vertical root fracture
What should be done to endo treated teeth to allow inside to settle?
Take out of occlusion
2 mm of cusp
How to improve prognosis of direct restorations in vital teeth
Slots/grooves
Better isolation
6-12 monthly reviews
What is necessary for a ferrule efect
A minimal height of 1.5-2 mm of intact tooth structure above the crown margin for 360 degrees around the circumference of the tooth preparation
How do we assess for fracture
Frac finder
Pain on release
Pain on biting - LEO
Why do we use fibre posts (4)
Posts provide retention of core
Fibre posts are more minimally invasive than metal posts
- Only need to be inserted half the root length whereas for metal depth = retention
Aesthetic
Easier to remove (for endo retreatment)
More fatigue resistant
Physical properties are similar to dentine (reducing risk of root fracture)
What materials are used for indirect restos
Gold
Zirconia
E-max
Metal/ceramic
