Establish the existence and orientation of dentinal tubules at level which resection is usually performed to determine pathways of leakage in apicected teeth.
- N=22 total. 1st group=10 teeth of unknown age, 2nd group = 12 teeth of known age
- 1st group: 2-4 mm removed at angles 45-60 degrees, sectioned roots longitudinally.
- 2nd group had 12 teeth of known age. Full length of root canal exposed without resection.
- In all apicected teeth, all had varying degrees of dentinal tubules exposed.
- At 3mm from apex- There were a mean of 27,000 tubules per mm square found and near dentine-cementum junction, there were 13,000 tubules per mm square.
Maintain bevel angle to a minimum due to exposure of dentinal tubules. Retrograde fillings should at least extend past the most coronal aspect of bevel to effectively seal exposed tubules.