What are teh types of tooth crack in increasing order of severity?
- Craze lines
- Fractured cusp
- Cracked tooth
- Split tooth
- Vertical root fracture
What are craze lines?
- Long vertical defects confined to enamel
- Generally not much of a problem, but may compromise aesthetics if stained
How do you distinguish between crack and craze lines?
- Transillumination
- If entire tooth lights up then craze line
- If part of tooth doesn’t light up then crack
What are teh signs/symptoms of fractured cusp?
- Occur due to weakened marginal ridge
- Progress obliquely towards CEJ or slightly subgingival
- Pt complain with pain on biting and temperature, especially with cold
- Symptoms may be relieved when cusp fractures off
- May need to remove restoration to check
- Pulp usually vital but may expect exagerrated response to cold
T/F functional cusps fracture more frequently than non-function cusps
F
What is cracked tooth?
- Crack that extends from occlusal towards the apical without segment separation (higher frequency of involving pulp vs cracked cusp)
- More related to heavy occlusal forces than restoration
Which tooth experiences cracked tooth most often?
Mandibular 2nd molar
What is a split tooth?
- Through and through crack of tooth which has progressed through to PDL
- Segments of tooth become separated
What is a vertical root fracture?
- Starts and confined to root surface
- Longitudinally oriented
- Extend from root canal into periodontium
What factors can predispose to cracked tooth?
- Posterior Bu cross bites
- Anterior open bites
- Steep cusps/fossas
- Parafunction
- AGe
- Width/depth of cavity
- Use of rotary instrumetns (greater removal of dentine at CEJ level)
What diagnostic tools can help diagnose coronal cracks?
- History/symptoms
- Reproduction of symptoms (percussion, frac finder, thermal tests)
- Visual (transillumination, mangification, restoration removal, staining)
- Radiographs
- Probing: determines extent of crack (if 6mm this indicates root affected which affects prognosis)
What are the sympotoms you would expect from cracked teeth?
- Sensitive to temperature, sometimes heat but especially cold (EPT normal response)
- Sensitive on biting
- Not TTP
- Most will respond positively to biting test (pain can sometimes be on biting or release)
How is pain in cracked cusp detected?
Hydronamic theory
How do you treat cracked tooth?
- If segment removed (split tooth) then remove the segment
- Restore (can condier crown lengthening if subgingival)
- Extraction
- CAuse/prevention
*CAn do provisional (cusp cap) restoration and review symptoms in 3 months to crown to confirm pulpitis was reversible
What is the usual amount of time before a tooth diagnosed with reversible pulpitis develops need for RCT?
Around a 6 year period 21% progressed (could be within 1 week to 6 years)
Which cracks have poor prognosis?
- Segement separation
- Crack crossing pulpal floor
- Periodontal pocketing or fracture line
- Damaging habits not amendable to change
What cracks have guarded prognosis?
-Crack extends down walls to floor of pulp chamber but does not run across the floor
What cracks have good prognosis?
-Crack has not reached pulpal floor
