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Load and strain during lateral condensation and vertical root fracture
V Lertchirakarn1, J E Palamara, H H Messer
1School of Dental Science, University of Melbourne, Victoria, Australia.
Journal of Endodontics
|April 16, 1999
Summary
Lateral condensation with finger spreaders generates lower root strains and loads than hand spreaders, suggesting finger spreaders reduce the risk of vertical root fracture during endodontic procedures.
Area of Science:
- Endodontics
- Dental Materials Science
- Biomechanics
Background:
- Vertical root fractures are a significant concern in endodontically treated teeth.
- Lateral condensation is a common obturation technique, but its potential to cause root fracture is debated.
Purpose of the Study:
- To compare vertical loads and root surface strains during lateral condensation using finger and hand spreaders.
- To evaluate the risk of vertical root fracture associated with different spreader types.
Main Methods:
- Extracted human teeth (incisors, premolars, molars) were subjected to lateral condensation using finger and hand spreaders.
- Strain gauges measured root surface strains at apical and middle thirds.
- Loads and strains were compared to fracture thresholds.
Main Results:
- Finger spreaders generated significantly lower loads and strains than hand spreaders (D11T).
- Both spreader types produced loads and strains well below fracture levels.
- Fracture patterns varied, with maxillary premolars and molars showing more complex fracture sites.
Conclusions:
- Lateral condensation alone is unlikely to be the primary cause of vertical root fracture.
- Using finger spreaders is associated with a lower risk of inducing root fracture compared to hand spreaders.
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